Species Proposed for Status Change or Delisting
3179 Records
Parameters:
- Listing Statuses: Species of Concern
When searching by State,
please note that a species will show up in the report only if it has a spatial current range.
State associations for a species are based on a spatial current range delineated by
FWS biologists in TESS (and not all species have spatial current range delineated at
the present time).
The current range of species entities consisting of one or more populations does not include states or countries outside those population boundaries, even though the species may occur there in a population not covered by the Endangered Species Act.
The current range of species entities consisting of one or more populations does not include states or countries outside those population boundaries, even though the species may occur there in a population not covered by the Endangered Species Act.
| Scientific Name | Common Name | Lead Region | Federal Listing Status | Where Listed |
|---|---|---|---|---|
| Abies fraseri | Fraser fir | 4 | Not Listed | Wherever found |
| Ablautus schlingeri | Oso Flaco robber fly | 1 | Not Listed | Wherever found |
| Abronia ammophila var. | No common name | 6 | Not Listed | Wherever found |
| Abronia ammphila | [Unnamed] sand-verbena | 6 | Not Listed | Wherever found |
| Abronia umbellata acutalata | Rose-purple sand-verbena | 1 | Not Listed | Wherever found |
| Abronia umbellata breviflora | Pink sand-verbena | 1 | Not Listed | Wherever found |
| Abutilon parishii | No common name | 2 | Not Listed | Wherever found |
| Abutilon virginianum | No common name | 4 | Not Listed | Wherever found |
| Acacia koaia | Koai`e | 1 | Not Listed | Wherever found |
| Acalyptera susanae | [Unnamed] lace bug | 4 | Not Listed | Wherever found |
| Acanthometropus pecatonica | Pecatonica River mayfly | 3 | Not Listed | Wherever found |
| Acanthomintha obovata obovata | San Benito thornmint | 1 | Not Listed | Wherever found |
| Accipiter cooperii | Cooper's hawk | 8 | Not Listed | Wherever found |
| Accipiter striatus | Sharp shinned hawk | 8 | Not Listed | Wherever found |
| Achnatherum contractum | No common name | 6 | Not Listed | Wherever found |
| Acleisanthes crassifolia | Texas trumpets | 2 | Not Listed | Wherever found |
| Acneus beeri | Beer's false water penny | 1 | Not Listed | Wherever found |
| Acneus burnelli | Burnell's false water penny | 1 | Not Listed | Wherever found |
| Acrolophitus pulchellus | Idaho pointheaded grasshopper | 1 | Not Listed | Wherever found |
| Acronicta albarufa | Barrens Dagger Moth | 5 | Not Listed | Wherever found |
| Adolphia californica | California adolphia | 8 | Not Listed | Wherever found |
| aechmophorus occidentalis | Western grebe | 7 | Not Listed | Wherever found |
| Aegialia concinna | Ciervo aegialian scarab | 1 | Not Listed | Wherever found |
| Aflexia rubranura | Redveined prairie leafhopper | 3 | Not Listed | Wherever found |
| Agalinis auriculata | Auriculate false-foxglove | 3 | Not Listed | Wherever found |
| Agapetus artesus | Artesian agapetus caddisfly | 3 | Not Listed | Wherever found |
| Agapetus denningi | Denning's agapetus caddisfly | 1 | Not Listed | Wherever found |
| Agapetus jocassee | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Agapetus medicus | Arkansas agapetus caddisfly | 4 | Not Listed | Wherever found |
| Agarodes alabamensis | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Agarodes stannardi | Stannard's agarodes caddisfly | 4 | Not Listed | Wherever found |
| Agarodes ziczac | Zigzag blackwater caddisfly | 4 | Not Listed | Wherever found |
| Agave glomeruliflora | Chisos agave | 2 | Not Listed | Wherever found |
| Agave murpheyi | No common name | 2 | Not Listed | Wherever found |
| Agave parviflora parviflora | Santa Cruz striped agave | 2 | Not Listed | Wherever found |
| Agave schottii treleasei | No common name | 2 | Not Listed | Wherever found |
| Agave shawii | Shaw's agave | 1 | Not Listed | Wherever found |
| Agave sp. | Sp. nov. ined. (Tonto Basin) agave | 2 | Not Listed | Wherever found |
| Ageratina luciae-brauniae | No common name | 4 | Not Listed | Wherever found |
| Agonum belleri | Beller's ground beetle | 1 | Not Listed | Wherever found |
| Agosia chrysogaster | Longfin dace | 2 | Not Listed | Wherever found |
| Agrimonia incisa | Incised groovebur | 4 | Not Listed | Wherever found |
| Agrostis blasdalei blasdalei | Blasdale's bentgrass | 1 | Not Listed | Wherever found |
| Agrostis hendersonii | Henderson's bentgrass | 1 | Not Listed | Wherever found |
| Agrostis howellii | Howell's bentgrass | 1 | Not Listed | Wherever found |
| Agrotis buchholzi | Buchholz' dart moth | 4 | Not Listed | Wherever found |
| Agrotis cremata | Cremata agrotis noctuid moth | 1 | Not Listed | Wherever found |
| Agrotis melanoneura | Black-veined agrotis noctuid moth | 1 | Not Listed | Wherever found |
| Agrotis microreas | Microreas agrotis noctuid moth | 1 | Not Listed | Wherever found |
| Agrotis potophila | Potophila agrotis noctuid moth | 1 | Not Listed | Wherever found |
| Aimophila aestivalis | Bachman's sparrow | 4 | Not Listed | Wherever found |
| Aimophila botterii texana | Texas Botteri's sparrow | 2 | Not Listed | Wherever found |
| Aimophila cassinii | Cassin's Sparrow | 6 | Not Listed | Wherever found |
| Aimophila ruficeps | Rufous-crowned Sparrow | 9 | Not Listed | Wherever found |
| Aimophila ruficeps canescens | Southern California rufous-crowned sparrow | 1 | Not Listed | Wherever found |
| Alabameubria starki | Stark's false water penny | 4 | Not Listed | Wherever found |
| Alasmidonta marginata | [Unnamed] elktoe | 6 | Not Listed | Wherever found |
| Alasmidonta wrightiana | Florida arc-mussel | 4 | Not Listed | Wherever found |
| Aletes humilis | No common name | 6 | Not Listed | Wherever found |
| Algamorda newcombiana | Newcomb's littorine snail | 1 | Not Listed | Wherever found |
| Allium aaseae | Aase's onion | 1 | Not Listed | Wherever found |
| Allium dictuon | Blue Mountain onion | 1 | Not Listed | Wherever found |
| allium haematochiton | Yucaipa onion | 6 | Not Listed | Wherever found |
| Allium hickmanii | Hickman's onion | 1 | Not Listed | Wherever found |
| Allium jepsonii | Jepson's onion | 1 | Not Listed | Wherever found |
| Allium shevockii | Spanish needle onion | 1 | Not Listed | Wherever found |
| Allium speculae | [Unnamed] onion | 4 | Not Listed | Wherever found |
| Allium tribracteatum | Siskiyou onion | 1 | Not Listed | Wherever found |
| Allocrangonyx hubrichti | Central Missouri cave amphipod | 3 | Not Listed | Wherever found |
| Allocrangonyx pellucidus | Oklahoma cave amphipod | 2 | Not Listed | Wherever found |
| Alloperla natchez | Natchez stonefly | 4 | Not Listed | Wherever found |
| Ambrosia linearis | [Unnamed] ambrosia | 6 | Not Listed | Wherever found |
| ambystoma gracile | Northwestern salamander | 7 | Not Listed | Wherever found |
| Ameiva wetmorei | Blue-tailed ground lizard | 4 | Not Listed | Wherever found |
| Amelanchier nantucketensis | [Unnamed] service-berry | 5 | Not Listed | Wherever found |
| Ameletus falsus | False ameletus mayfly | 2 | Not Listed | Wherever found |
| Ammocrypta pellucida | Eastern sand darter | 5 | Not Listed | Wherever found |
| Ammodramus caudacutus | Saltmarsh Sparrow | 9 | Not Listed | Wherever found |
| Ammodramus savannarum | Grasshopper Sparrow | 1 | Not Listed | Wherever found |
| Ammodramus savannarum ssp. perpallidus | Grasshopper sparrow | 8 | Not Listed | Wherever found |
| Ammonitella yatesii | Yates' tight coin | 1 | Not Listed | Wherever found |
| Ammopelmatus kelsoensis | Kelso jerusalem cricket | 1 | Not Listed | Wherever found |
| Ammopelmatus muwu | Point Conception jerusalem cricket | 1 | Not Listed | Wherever found |
| Ammospermophilus nelsoni | Nelson's antelope ground squirrel | 1 | Not Listed | Wherever found |
| Amorpha ouachitensis | [Unnamed] false indigo | 2 | Not Listed | Wherever found |
| Amphigyra alabamensis | Shoal sprite | 4 | Not Listed | Wherever found |
| Amphispiza belli belli | Bell's sage sparrow | 1 | Not Listed | Wherever found |
| Amsinckia vernicosa furcata | Forked fiddleneck | 1 | Not Listed | Wherever found |
| Amsonia fugatei | No common name | 2 | Not Listed | Wherever found |
| Amsonia grandiflora | [Unnamed] blue-star | 2 | Not Listed | Wherever found |
| Amsonia tabernaemontana gattingeri | No common name | 4 | Not Listed | Wherever found |
| anacolia menziesii | Menzies' anacolia moss | 6 | Not Listed | Wherever found |
| Anas bahamensis bahamensis | Lesser white-cheeked pintail | 4 | Not Listed | Wherever found |
| Anchotefflus gracilis | Gracile anchotefflus ground beetle | 1 | Not Listed | Wherever found |
| Aneides hardii | Sacramento mountain salamander | 2 | Not Listed | Wherever found |
| Anemone edwardsiana petraea | Edge Falls anemone | 2 | Not Listed | Wherever found |
| Angelica scabrida | No common name | 1 | Not Listed | Wherever found |
| Anniella pulchra pulchra | Silvery legless lizard | 1 | Not Listed | Wherever found |
| Anodontoides denigrata | Cumberland papershell | 4 | Not Listed | Wherever found |
| Anolis occultus | Puerto Rican pygmy anole | 4 | Not Listed | Wherever found |
| Anomala exigua | Exiguous anomalan scarab | 4 | Not Listed | Wherever found |
| Anomala eximia | Archbold anomalan scarab | 4 | Not Listed | Wherever found |
| Anomala tibialis | Tibial scarab | 2 | Not Listed | Wherever found |
| Anomis vulpicolor | Red anomis noctuid moth | 1 | Not Listed | Wherever found |
| Antennaria arcuata | Meadow pussytoes | 1 | Not Listed | Wherever found |
| Antennaria soliceps | No common name | 1 | Not Listed | Wherever found |
| Anthicus antiochensis | Antioch Dunes anthicid | 1 | Not Listed | Wherever found |
| Anthicus sacramento | Sacramento anthicid | 1 | Not Listed | Wherever found |
| antrozous pallidus | Pallid bat | 2 | Not Listed | Wherever found |
| anulocaulis leiosolenus | Sticky ringstem | 6 | Not Listed | Wherever found |
| Apamea smythi | Smyth's apamea moth | 3 | Not Listed | Wherever found |
| Apatania tavala | Cascades apatanian caddisfly | 1 | Not Listed | Wherever found |
| Aphanisma blitoides | Aphanisma | 1 | Not Listed | Wherever found |
| Aphaostracon xynoelictum | Fenney Spring hydrobe | 4 | Not Listed | Wherever found |
| Aphelocoma coerulescens cana | Eagle Mountain scrub jay | 1 | Not Listed | Wherever found |
| Aphelocoma insularis | Island Scrub-Jay | 9 | Not Listed | Wherever found |
| Aphodius fordi | Ford's aphodius scarab | 4 | Not Listed | Wherever found |
| Aphodius sp. | Sand Mountain aphodius scarab | 1 | Not Listed | Sand Mt. |
| Aphodius sp. | Big Dune aphodius scarab | 1 | Not Listed | Big Dune |
| Aphodius sp. | Crescent Dune aphodius scarab | 1 | Not Listed | Crescent Dune |
| Aphodius troglodytes | Aphodius tortoise commensal scarab | 4 | Not Listed | Wherever found |
| aphrastochthonius | (Aphrastochthonius) pseudoscorpion | 6 | Not Listed | Wherever found |
| Aphrastochthonius grubbsi | Grubbs' cave pseudoscorpion | 1 | Not Listed | Wherever found |
| Aphrastochthonius similis | Carlow's Cave pseudoscorpion | 1 | Not Listed | Wherever found |
| Aplodontia rufa californica | Mountain beaver | 1 | Not Listed | Wherever found |
| Aplodontia rufa phaea | Point Reyes mountain beaver | 1 | Not Listed | Wherever found |
| Apochthonius malheuri | Malheur pseudoscorpion | 1 | Not Listed | Wherever found |
| Apochthonius paucispinosus | Dry Fork Valley cave pseudoscorpion | 5 | Not Listed | Wherever found |
| Appalachia arcana | Michigan bog grasshopper | 3 | Not Listed | Wherever found |
| Apterocyclus honoluluensis | Kauai flightless stag beetle | 1 | Not Listed | Wherever found |
| Aquila chrysaetos | Golden eagle | 7 | Not Listed | Wherever found |
| Aquilegia canadensis australis | Canadian, columbine | 4 | Not Listed | Wherever found |
| Aquilegia chrysantha hinckleyana | Hinckley's columbine | 2 | Not Listed | Wherever found |
| Aquilegia laramiensis | Laramie columbine | 6 | Not Listed | Wherever found |
| Aquilegia longissima | Long spur columbine | 2 | Not Listed | Wherever found |
| Arabis bodiensis | Bodie Hills rock-cress | 1 | Not Listed | Wherever found |
| Arabis breweri pecuniaria | San Bernardino rock-cress | 1 | Not Listed | Wherever found |
| Arabis falcifructa | [Unnamed] rock-cress | 1 | Not Listed | Wherever found |
| Arabis fecunda | Sapphire Mt. rock-cress | 6 | Not Listed | Wherever found |
| Arabis koehleri koehleri | Koehler's rock-cress | 1 | Not Listed | Wherever found |
| Arabis mcdonaldiana | Preston Peak rock-cress | 1 | Not Listed | Wherever found |
| Arabis missouriensis deamii | No common name | 3 | Not Listed | Wherever found |
| Arabis ophira | [Unnamed] rock-cress | 1 | Not Listed | Wherever found |
| Arabis parishii | Parish's rock-cress | 1 | Not Listed | Wherever found |
| Arabis rigidissima demota | Galena Creek rock-cress | 1 | Not Listed | Wherever found |
| Arabis sp. | Sp. nov. ined. (Del Norte) rock-cress | 1 | Not Listed | Del Norte |
| Arabis suffrutescens horizontalis | No common name | 1 | Not Listed | Wherever found |
| Arabis tiehmii | Tiehm's rock-cress | 1 | Not Listed | Wherever found |
| Arabis vivariensis | Park rock-cress | 6 | Not Listed | Wherever found |
| Arborimus albipes | White-footed vole | 1 | Not Listed | Wherever found |
| Arborimus pomo | California red tree vole | 1 | Not Listed | Wherever found |
| Archeolarca aalbui | Aalbu's cave pseudoscorpion | 1 | Not Listed | Wherever found |
| Archoplites interruptus | Sacramento perch | 1 | Not Listed | Wherever found |
| Arctomecon merriamii | White bear desert-poppy | 1 | Not Listed | Wherever found |
| Arctostaphylos andersonii | Santa Cruz manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos catalinae | Santa Catalina Island manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos cruzensis | Arroyo de la Cruz manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos densiflora | Vine Hill manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos edmundsii | Little Sur manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos gabrielensis | San Gabriel manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos glutinosa | Schreiber's manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos hookeri hearstiorum | Hearsts' manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos hookeri montana | Tamalpais manzanita | 1 | Not Listed | Wherever found |
| arctostaphylos hookeri ssp. hookeri | Hooker's manzanita | 6 | Not Listed | Wherever found |
| Arctostaphylos klamathensis | Klamath manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos luciana | Santa Lucia manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos montaraensis | Montara manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos montereyensis | Monterrey manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos nissenana | Nissenan manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos nortensis | Del Norte manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos osoensis | Oso manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos otayensis | Otay manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos pajaroensis | Pajaroensis manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos pechoensis | Pecho manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos pilosula pilosula | Santa Margarita manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos pumila | Sandmat manzanita | 1 | Not Listed | Wherever found |
| arctostaphylos rainbowensis | Rainbow manzanita | 6 | Not Listed | Wherever found |
| Arctostaphylos refugioensis | Refugio manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos rudis | Sand mesa manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos silvicola | Bonny Doon manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos stanfordiana raichei | Raiches manzanita | 1 | Not Listed | Wherever found |
| Arctostaphylos tomentosa daciticola | Dacite manzanita | 1 | Not Listed | Wherever found |
| Ardea herodias | Great blue heron | 7 | Not Listed | Wherever found |
| Arenaria kingii rosea | No common name | 1 | Not Listed | Wherever found |
| Arenaria macradenia kuschei | Forest Camp sandwort | 1 | Not Listed | Wherever found |
| Areniscythris brachypteris | Oso Flaco flightless moth | 1 | Not Listed | Wherever found |
| Argia sp. | Balmorhea damselfly | 2 | Not Listed | Balmorhea |
| Argyresthia castaneela | Chestnut ermine moth | 5 | Not Listed | Wherever found |
| Argyroxiphium caliginis | Eke silversword | 1 | Not Listed | Wherever found |
| Argythamnia aphoroides | Wild, Hill Country mercury | 2 | Not Listed | Wherever found |
| Arianops sandersoni | Magazine Mountain mold beetle | 4 | Not Listed | Wherever found |
| Aristida simpliciflora | Southern three-awned grass | 4 | Not Listed | Wherever found |
| arizona elegans | Glossy snake | 2 | Not Listed | Wherever found |
| Arnica lonchophylla | No common name | 3 | Not Listed | Wherever found |
| Arremonops rufivirgatus rufivirgatus | Texas olive sparrow | 2 | Not Listed | Wherever found |
| Arrhyton exiguum exiguum | Culebra garden snake | 4 | Not Listed | Wherever found |
| Artemia monica | Mono Lake brine shrimp | 1 | Not Listed | Wherever found |
| Artemisia biennis diffusa | No common name | 6 | Not Listed | Wherever found |
| Artemisia globularia lutea | [Unnamed] wormwood | 7 | Not Listed | Wherever found |
| Artemisia glomerata subglabra | [Unnamed] wormwood | 7 | Not Listed | Wherever found |
| Artemisia ludoviciana estesii | No common name | 1 | Not Listed | Wherever found |
| artemisia palmeri | San Diego sagewort | 6 | Not Listed | Wherever found |
| Artemisiospiza belli | Bells Sparrow | 6 | Not Listed | Wherever found |
| Arthonia cupressina | Golden spruce dots | 4 | Not Listed | |
| Arthonia kermesina | Hot dots | 4 | Not Listed | |
| Arthopyrenia betulicola | Old birch spots | 4 | Not Listed | |
| Asaphomyia floridensis | Florida asaphomyian tabanid fly | 4 | Not Listed | Wherever found |
| Asaphomyia texanus | Texas asaphomyian tabanid fly | 2 | Not Listed | Wherever found |
| Ascaphus truei | Tailed frog | 1 | Not Listed | Wherever found |
| Ascetocthere cosmeta | Grayson crayfish ostracod | 4 | Not Listed | Wherever found |
| Asclepias eastwoodiana | Eastwood's milkweed | 1 | Not Listed | Wherever found |
| Asclepias uncialis | [Unnamed] milkweed | 6 | Not Listed | Wherever found |
| Asclepias viridula | [Unnamed] milkweed | 4 | Not Listed | Wherever found |
| Ashmunella pasonis | Franklin Mountain wood snail | 2 | Not Listed | Wherever found |
| Asio flammeus | Short-eared Owl | 6 | Not Listed | Wherever found |
| Asio flammeus sandwichensis | Hawaiian short-eared owl | 1 | Not Listed | Wherever found |
| asio otus | Long-eared owl | 7 | Not Listed | Wherever found |
| Aspiduchus cavernicola | Tuna Cave roach | 4 | Not Listed | Wherever found |
| Aspiromitus appalachianus | A Hornwort | 4 | Not Listed | |
| Asplenium heteroresiliens | [Unnamed] spleenwort | 4 | Not Listed | Wherever found |
| Asplenium plenum | [Unnamed] spleenwort | 4 | Not Listed | Wherever found |
| Asplenium schizophyllum | No common name | 1 | Not Listed | Wherever found |
| Assiminea infima | Badwater snail | 1 | Not Listed | Wherever found |
| Aster chilensis lentus | Suisun aster | 1 | Not Listed | Wherever found |
| Aster kingii barnebyana | No common name | 6 | Not Listed | Wherever found |
| Aster laevis guadalupensis | Guadalupe smooth aster | 2 | Not Listed | Wherever found |
| Astilbe crenatiloba | Roan Mountain false goats beard | 4 | Not Listed | Wherever found |
| Astragalus aequalis | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus agnicidus | Humboldt milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus amphioxys musimonum | No common name | 1 | Not Listed | Wherever found |
| Astragalus ampullarius | Gumbo milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus anisus | Gunnison milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus atratus inseptus | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus brandegeei | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus cobrensis maguirei | Coppermine milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus collinus laurentii | No common name | 1 | Not Listed | Wherever found |
| Astragalus columbianus | Columbia milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus cottonii | Cotton's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus cremnophylax myriorrhaphis | Cliff milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus cronquistii | Cronquist milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus deanei | Deane's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus deterior | Cliff-palace milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus diaphanus diurnus | No common name | 1 | Not Listed | Wherever found |
| Astragalus douglasii perstrictus | Jacumba milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus drabelliformis | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus ertterae | Ertter's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus eurylobus | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus funereus | Black wooly-pod | 1 | Not Listed | Wherever found |
| Astragalus gilmanii | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus gilviflorus var. purpureus | No common name | 6 | Not Listed | Wherever found |
| Astragalus howellii | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus jejunus articulatus | No common name | 6 | Not Listed | Wherever found |
| Astragalus kerrii | Kerr's milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus knightii | [Unnamed] milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus lentiformis | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus lentiginosus ambiguus | No common name | 2 | Not Listed | Wherever found |
| Astragalus lentiginosus antonius | No common name | 1 | Not Listed | Wherever found |
| Astragalus lentiginosus pohlii | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus lentiginosus scorpionis | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus lentiginosus sierrae | Big Bear milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus leucolobus | Bear Valley wooly-pod | 1 | Not Listed | Wherever found |
| Astragalus limnocharis limnocharis | No common name | 6 | Not Listed | Wherever found |
| Astragalus limnocharis tabulaeus | No common name | 6 | Not Listed | Wherever found |
| Astragalus michauxii | Sandhills milk-vetch | 4 | Not Listed | Wherever found |
| Astragalus mohavensis hemigyrus | Curve-podded Mojave milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus mollissimus marcidus | Withered wooly milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus molybdenus | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus monoensis monoensis | Mono milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus monoensis ravenii | Raven's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus mulfordiae | Mulford's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus neglectus | [Unnamed] milk-vetch | 3 | Not Listed | Wherever found |
| Astragalus nevinii | San Clemente Island milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus nutriosensis | Nutriosa milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus oocarpus | Descanso milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus oophorus lavinii | Lavin's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus oophorus lonchocalyx | No common name | 1 | Not Listed | Wherever found |
| Astragalus pachypus jaegeri | Jaeger's bush milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus paysonii | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus peckii | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus preussii cutleri | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus proximus | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus pulsiferae suksdorfii | No common name | 1 | Not Listed | Wherever found |
| Astragalus remotus | Spring Mountain milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus ripleyi | Ripley milk-vetch | 2 | Not Listed | Wherever found |
| Astragalus robbinsii occidentalis | Robbins, western ssp. milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus serpens | [Unnamed] milk-vetch | 6 | Not Listed | Wherever found |
| Astragalus sinuatus | Whited milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus solitarius | Weak milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus subcinereus basalticus | No common name | 6 | Not Listed | Wherever found |
| Astragalus tegetarioides | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus tener var. ferrisae | Ferris' milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus tener var. tener | Alkali milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus tiehmii | Tiehm's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus traskiae | Trask's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus tyghensis | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus uncialis | [Unnamed] milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus vexilliflexus nubilus | No common name | 1 | Not Listed | Wherever found |
| Astragalus webberi | Webber's milk-vetch | 1 | Not Listed | Wherever found |
| Astragalus xiphoides | Gladiator milk-vetch | 2 | Not Listed | Wherever found |
| Ataenius superficialis | Big Pine Key ataenius dung beetle | 4 | Not Listed | Wherever found |
| Ataenius woodruffi | Woodruff's ataenius dung beetle | 4 | Not Listed | Wherever found |
| Atelothrus transiens | Transient atelothrus ground beetle | 1 | Not Listed | Wherever found |
| Athene cunicularia | Burrowing Owl | 9 | Not Listed | Wherever found |
| Athene cunicularia ssp. hypugaea | Western burrowing owl | 1 | Not Listed | Wherever found |
| Atractelmis wawona | Wawona riffle beetle | 1 | Not Listed | Wherever found |
| Atriplex canescens gigantea | No common name | 6 | Not Listed | Wherever found |
| Atriplex cordulata | Heartscale | 1 | Not Listed | Wherever found |
| Atriplex coulteri | Coulter's saltbush | 1 | Not Listed | Wherever found |
| Atriplex joaquiniana | Valley spearscale | 1 | Not Listed | Wherever found |
| atriplex minuscula | Lesser saltbrush | 6 | Not Listed | Wherever found |
| Atriplex pacifica | South coast saltbush | 1 | Not Listed | Wherever found |
| Atriplex parishii | Parrish's brittlescale | 1 | Not Listed | Wherever found |
| atriplex serenana var. davidsonii | Davidson's saltscale | 6 | Not Listed | Wherever found |
| Atriplex tularensis | Bakersfield saltbush | 1 | Not Listed | Wherever found |
| Atriplex vallicola | Lost Hills saltbush | 1 | Not Listed | Wherever found |
| Atrytone arogos arogos | Eastern beard grass Skipper | 5 | Not Listed | Wherever found |
| Aureolaria patula | No common name | 4 | Not Listed | Wherever found |
| Austrotinodes sp. | Texas austrotinodes caddisfly | 2 | Not Listed | Wherever found |
| Aythya affinis | Lesser scaup | 4 | Not Listed | Wherever found |
| Baeolophus inornatus | Oak Titmouse | 9 | Not Listed | Wherever found |
| balsamorhiza macrolepis var. macrolepis | Big scale balsamroot | 6 | Not Listed | Wherever found |
| Banza nihoa | Nihoa banza conehead katydid | 1 | Not Listed | Wherever found |
| Baptisia calycosa calycosa | No common name | 4 | Not Listed | Wherever found |
| Baptisia calycosa villosa | Hairy wild indigo | 4 | Not Listed | Wherever found |
| Baptisia simplicifolia | No common name | 4 | Not Listed | Wherever found |
| Bartramia longicauda | Upland Sandpiper | 6 | Not Listed | Wherever found |
| bassariscus astutus | Ringtail | 6 | Not Listed | Wherever found |
| batrachoseps nigriventris | Black-bellied slender salamander | 6 | Not Listed | Wherever found |
| Batrachoseps pacificus pacificus | Channel Islands slender salamander | 1 | Not Listed | Wherever found |
| Batrachoseps sp. | Breckenridge Mountain slender salamander | 1 | Not Listed | Wherever found |
| Bazzania nudicaulis | No common name | 4 | Not Listed | Wherever found |
| Belocephalus micanopy | Big Pine Key conehead katydid | 4 | Not Listed | Wherever found |
| Belocephalus sleighti | Keys shortwinged conehead katydid | 4 | Not Listed | Wherever found |
| Beloneuria jamesae | Cheaha beloneurian stonefly | 4 | Not Listed | Wherever found |
| Belostoma saratogae | Saratoga Springs belostoman bug | 1 | Not Listed | Wherever found |
| bembidion gordoni | (Bembidion gordoni) ground beetle | 8 | Not Listed | Wherever found |
| bembidion stillaguamish | (Bembidion stillaguamish) ground beetle | 8 | Not Listed | Wherever found |
| bembidion viator | (Bembidion viator) ground beetle | 8 | Not Listed | Wherever found |
| Bensoniella oregona | Bensoniella | 1 | Not Listed | Wherever found |
| Berberis nervosa mendocinensis | Hardy Creek barberry | 1 | Not Listed | Wherever found |
| Betula murrayana | [Unnamed] birch | 3 | Not Listed | Wherever found |
| Bidens bidentoides bidentoides | [Unnamed] bur-marigold | 5 | Not Listed | Wherever found |
| Bidens bidentoides mariana | Maryland bur-marigold | 5 | Not Listed | Wherever found |
| Bidens sandvicensis confusa | Ko`oko`olau | 1 | Not Listed | Wherever found |
| Binneya notabilis | Santa Barbara shelled slug | 1 | Not Listed | Wherever found |
| Blackburnia insignis | Oahu blackburnia ground beetle | 1 | Not Listed | Wherever found |
| Blarina brevicauda compacta | Nantucket short-tailed shrew | 5 | Not Listed | Wherever found |
| Blarina hylophaga plumbea | Aransas short-tailed shrew | 2 | Not Listed | Wherever found |
| Blennosperma nanum robustum | Point Reyes stickyseed | 1 | Not Listed | Wherever found |
| Bloomeria humilis | Dwarf goldenstar | 1 | Not Listed | Wherever found |
| Bobea timonioides | `Ahakea | 1 | Not Listed | Wherever found |
| Boechera pinzliae | Boundary Peak rock-cress | 1 | Not Listed | Wherever found |
| Boerhavia mathisiana | Mathis spiderling | 2 | Not Listed | Wherever found |
| Boltonia apalachicolensis | Apalachicola doll's daisy | 4 | Not Listed | Wherever found |
| Botaurus lentiginosus | American bittern | 7 | Not Listed | Wherever found |
| Botrychium ascendens | Trianglelobe moonwort | 1 | Not Listed | Wherever found |
| Botrychium crenulatum | No common name | 1 | Not Listed | Wherever found |
| Botrychium gallicomontanum | Prairie moonwort | 3 | Not Listed | Wherever found |
| Botrychium mormo | No common name | 3 | Not Listed | Wherever found |
| Botrychium pallidum | No common name | 6 | Not Listed | Wherever found |
| Botrychium paradoxum | No common name | 6 | Not Listed | Wherever found |
| Botrychium pedunculosum | Stalked moonwort | 1 | Not Listed | Wherever found |
| Botrychium pumicola nealleyi | Crater Lake grap fern | 1 | Not Listed | Wherever found |
| Botrychium subbifoliatum | Makou | 1 | Not Listed | Wherever found |
| Brachionidium ciliolatum | Makou | 4 | Not Listed | Wherever found |
| Brachycercus flavus | Yellow brachycercus mayfly | 4 | Not Listed | Wherever found |
| Brachymenium andersonii | Anderson's brachymenium | 4 | Not Listed | Wherever found |
| Brachyramphus marmoratus | Marbled murrelet | 7 | Not Listed | Entire, except U.S.A. (CA, OR, WA) |
| bradycellus fenderi | (Bradycellus fenderi) ground beetle | 8 | Not Listed | Wherever found |
| Brickellia brachyphylla montanus | Hinckley's bricklebush | 1 | Not Listed | Wherever found |
| Brickellia brachyphylla terlinguensis | Terlingua bricklebush | 2 | Not Listed | Wherever found |
| Brickellia cordifolia | Flyr's brickell-bush | 4 | Not Listed | Wherever found |
| Brickellia viejensis | Sierra Vieja brickellia | 2 | Not Listed | Wherever found |
| Brodiaea coronaria rosea | Indian Valley brodiaea | 1 | Not Listed | Wherever found |
| Brodiaea insignis | Kaweah brodiaea | 1 | Not Listed | Wherever found |
| Brodiaea kinkiensis | San Clemente Island brodiaea | 1 | Not Listed | Wherever found |
| Brodiaea orcuttii | Orcutt's brodiaea | 1 | Not Listed | Wherever found |
| Brongniartia minutifolia | Little-leaf brongniartia | 2 | Not Listed | Wherever found |
| Browallia sp. | Sp. nov. ined. browallia | 2 | Not Listed | Wherever found |
| Brunfelsia portoricensis | No common name | 4 | Not Listed | Wherever found |
| Bryania bipunctata | Nihoa two-spotted asteriid fly | 1 | Not Listed | Wherever found |
| Bryocrumia vivicolor | Gorge moss | 4 | Not Listed | Wherever found |
| Buckleya distichophylla | Piratebush | 4 | Not Listed | Wherever found |
| Buellia sharpiana | Evelyn''s buttons | 4 | Not Listed | |
| bufo alvarius | Colorado River toad | 6 | Not Listed | Wherever found |
| Bufo boreas | Western toad | 1 | Not Listed | Wherever found |
| Bufo exsul | Black toad | 1 | Not Listed | Wherever found |
| Buteo brachyurus | short-tailed hawk | 4 | Not Listed | Wherever found |
| buteo lagopus | Rough-legged hawk | 7 | Not Listed | Wherever found |
| buteo lineatus | Red-shouldered hawk | 6 | Not Listed | Wherever found |
| Buteo nitidus maximus | Northern gray hawk | 2 | Not Listed | Wherever found |
| Buteo swainsoni | Swainson's hawk | 3 | Not Listed | CA, NV, OR, CO, AZ or Wherever found |
| Byrsonima lucida | Maricao cimarron | 4 | Not Listed | Wherever found |
| Byrsonima spicata | Maricao cimarron | 4 | Not Listed | Wherever found |
| Caconemobius howarthi | Howarth's cave cricket | 1 | Not Listed | Wherever found |
| Caconemobius schauinslandi | Schauinsland's bush cricket | 1 | Not Listed | Wherever found |
| Caconemobius varius | Kaumana Cave cricket | 1 | Not Listed | Wherever found |
| Caecidotea barri | Clifton Cave isopod | 4 | Not Listed | Wherever found |
| Caecidotea cannulus | [Unnamed] isopod | 5 | Not Listed | Wherever found |
| Caecidotea carolinensis | Bennets Mill Cave water slater | 4 | Not Listed | Wherever found |
| Caecidotea filicispeluncae | [Unnamed] isopod | 3 | Not Listed | Wherever found |
| Caecidotea franzi | Franz's isopod | 5 | Not Listed | Wherever found |
| Caecidotea macropropoda | Bat Cave isopod | 2 | Not Listed | Wherever found |
| Caecidotea nickajackensis | Nickajack Cave isopod | 4 | Not Listed | Wherever found |
| caecidotea reddelli | (Caecidotea reddelli) isopod | 6 | Not Listed | Wherever found |
| Caecidotea simonini | [Unnamed] isopod | 5 | Not Listed | Wherever found |
| Caecidotea sinuncus | [Unnamed] isopod | 5 | Not Listed | Wherever found |
| Caecidotea tomalensis | [Unnamed] isopod | 1 | Not Listed | Wherever found |
| Caecidotea tridentata | No common name | 6 | Not Listed | Wherever found |
| Caesalpinia brachycarpa | Broad-pod rushpea | 2 | Not Listed | Wherever found |
| Caesalpinia culebrae | Amarillo mato | 4 | Not Listed | Wherever found |
| Calamagrostis cainii | Cain's reedgrass | 4 | Not Listed | Wherever found |
| Calamagrostis crassiglumis | Thurber's reedgrass | 1 | Not Listed | Wherever found |
| Calamagrostis perplexa | Wood reedgrass | 5 | Not Listed | Wherever found |
| Calamagrostis porteri insperata | Ofer Hollow reedgrass | 3 | Not Listed | Wherever found |
| Calamovilfa curtissii | [Unnamed] sand grass | 4 | Not Listed | Wherever found |
| Calcarius mccownii | McCown's Longspur | 6 | Not Listed | Wherever found |
| Calcina minor | Edgewood blind harvestman | 1 | Not Listed | Wherever found |
| Calidris subruficollis | Buff-breasted Sandpiper | 6 | Not Listed | Wherever found |
| Callitriche marginata | winged water-starwort | 1 | Not Listed | Wherever found |
| calochortus catalinae | Catalina mariposa lily | 6 | Not Listed | Wherever found |
| Calochortus clavatus avius | Pleasant Valley mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus clavatus gracilis | Slender mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus clavatus recurvifolius | Arroyo de la Cruz mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus coxii | Cox's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus dunnii | Dunn's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus excavatus | Inyo mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus greenei | Greene's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus howellii | Howell's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus indecorus | [Unnamed] mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus longebarbatus longebarbatus | Long-haired star-tulip | 1 | Not Listed | Wherever found |
| Calochortus longebarbatus peckii | Long-bearded, Peck's mariposa | 1 | Not Listed | Wherever found |
| Calochortus monanthus | Shasta River mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus nitidus | No common name | 1 | Not Listed | Wherever found |
| Calochortus palmeri munzii | Munz's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus palmeri palmeri | Palmer's mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus plummerae | Plummer's mariposa lily | 1 | Not Listed | Wherever found |
| calochortus pulchellus | Recurved larkspur | 6 | Not Listed | Wherever found |
| Calochortus raichei | The Cedars globe-lily | 1 | Not Listed | Wherever found |
| Calochortus striatus | Alkali mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus weedii intermedius | Foothill mariposa lily | 1 | Not Listed | Wherever found |
| Calochortus weedii vestus | No common name | 1 | Not Listed | Wherever found |
| Calochortus westonii | Shirley Meadows mariposa lily | 1 | Not Listed | Wherever found |
| Calycadenia fremontii | Fremont's rosinweed | 1 | Not Listed | Wherever found |
| Calycadenia hooveri | Hoover's rosinweed | 1 | Not Listed | Wherever found |
| Calypte costae | Costa's Hummingbird | 6 | Not Listed | Wherever found |
| Calyptranthes luquillensis | No common name | 4 | Not Listed | Wherever found |
| Calyptranthes peduncularis | No common name | 4 | Not Listed | Wherever found |
| Calyptranthes triflorum | No common name | 4 | Not Listed | Wherever found |
| Calystegia atriplicifolia buttensis | Butte County morning-glory | 1 | Not Listed | Wherever found |
| Calystegia collina oxyphylla | Mt. Saint Helena morning-glory | 1 | Not Listed | Wherever found |
| Calystegia collina venusta | South Coast Range morning-glory | 1 | Not Listed | Wherever found |
| Calystegia macrostegia amplissima | Island morning-glory | 1 | Not Listed | Wherever found |
| Calystegia peirsonii | Peirson's morning-glory | 1 | Not Listed | Wherever found |
| Calystegia subacaulis episcopalis | Cambria morning-glory | 1 | Not Listed | Wherever found |
| Camassia howellii | No common name | 1 | Not Listed | Wherever found |
| Cambarus englishi | Tallapoosa River crayfish | 4 | Not Listed | Wherever found |
| Cambarus hiwasseensis | Hiwassee headwater crayfish | 4 | Not Listed | Wherever found |
| Cambarus miltus | [Unnamed] crayfish | 4 | Not Listed | Wherever found |
| Cambarus reburrus | French Broad crayfish | 4 | Not Listed | Wherever found |
| Camissonia atwoodii | No common name | 6 | Not Listed | Wherever found |
| Camissonia guadalupensis clementina | San Clemente Island evening-primrose | 1 | Not Listed | Wherever found |
| Camissonia hardhamiae | Hardham's evening-primrose | 1 | Not Listed | Wherever found |
| Camissonia megalantha | [Unnamed] evening-primrose | 1 | Not Listed | Wherever found |
| Camissonia sierrae alticola | Mono Hot Springs evening-primrose | 1 | Not Listed | Wherever found |
| Camissonia specuicola hesperia | [Unnamed] evening-primrose | 2 | Not Listed | Wherever found |
| Campanula californica | Swamp harebell | 1 | Not Listed | Wherever found |
| campanula exigua | Chaparral harebell | 6 | Not Listed | Wherever found |
| Campanula sharsmithiae | Mt. Hamilton harebell | 1 | Not Listed | Wherever found |
| Campanula wilkinsiana | Wilkin's harebell | 1 | Not Listed | Wherever found |
| Campostoma ornatum | Mexican stoneroller | 2 | Not Listed | Wherever found |
| Campsicnemus mirabilis | Ko`olau spurwing long-legged fly | 1 | Not Listed | Wherever found |
| Campylopus carolinae | Savannah campylopus | 4 | Not Listed | Wherever found |
| Campylorhynchus brunneicapillus | Cactus Wren | 1 | Not Listed | Wherever found |
| canis latrans | coyote | 7 | Not Listed | Wherever found |
| Canna pertusa | Maraca | 4 | Not Listed | Wherever found |
| Capnia lacustra | Lake Tahoe benthic stonefly | 1 | Not Listed | Wherever found |
| Capparis sandwichiana | Pua pilo | 1 | Not Listed | Wherever found |
| Cardamine clematitis | Mountain bittercress | 4 | Not Listed | Wherever found |
| Cardamine nuttallii | Yellow-tubered toothwort | 1 | Not Listed | Wherever found |
| Cardamine pattersonii | Saddle Mountain bittercress | 1 | Not Listed | Wherever found |
| Carduelis lawrencei | Lawrence's Goldfinch | 6 | Not Listed | Wherever found |
| Carelia spp. (ca 12) | Spp. (ca 12) carelia | 1 | Not Listed | Wherever found |
| Carex baltzellii | [Unnamed] sedge | 4 | Not Listed | Wherever found |
| Carex bicknellii opaca | [Unnamed] sedge | 4 | Not Listed | Wherever found |
| Carex chapmanii | Chapman's sedge | 4 | Not Listed | Wherever found |
| Carex communis var. amplisquama | Fort Mountain Sedge | 4 | Not Listed | Wherever found |
| Carex fissa | [Unnamed] sedge | 2 | Not Listed | Wherever found |
| Carex formosa | [Unnamed] sedge | 3 | Not Listed | Wherever found |
| Carex haysii | [Unnamed] sedge | 6 | Not Listed | Wherever found |
| Carex hyalina | Tissue sedge | 2 | Not Listed | Wherever found |
| Carex latebracteata | Waterfall's sedge | 2 | Not Listed | Wherever found |
| Carex lenticularis dolia | [Unnamed] sedge | 7 | Not Listed | Wherever found |
| Carex manhartii | Manhart's sedge | 4 | Not Listed | Wherever found |
| Carex oronensis | [Unnamed] sedge | 5 | Not Listed | Wherever found |
| Carex polymorpha | Variable sedge | 5 | Not Listed | Wherever found |
| Carex radfordii | Radford's sedge | 4 | Not Listed | Wherever found |
| Carex roanensis | [Unnamed] sedge | 4 | Not Listed | Wherever found |
| Carex schweinitzii | [Unnamed] sedge | 5 | Not Listed | Wherever found |
| Carex wahuensis herbstii | No common name | 1 | Not Listed | Wherever found |
| Carolella busckana | Busck's gall moth | 1 | Not Listed | Wherever found |
| Carpodacus cassinii | Cassin's Finch | 6 | Not Listed | Wherever found |
| Carposina viridis | Green carposinid moth | 1 | Not Listed | Wherever found |
| Carterocephalus palaemon ssp. | Sonoma arctic skipper | 1 | Not Listed | Wherever found |
| Cassia fasciculata macrosperma | No common name | 5 | Not Listed | Wherever found |
| Castilleja ambigua humboldtiensis | Humboldt Bay owl's clover | 1 | Not Listed | Wherever found |
| Castilleja applegatei ssp. martinii | Clokey paintbrush | 6 | Not Listed | Wherever found |
| Castilleja chlorotica | Green-tinged paintbrush | 1 | Not Listed | Wherever found |
| Castilleja cryptantha | Obscure Indian paintbrush | 1 | Not Listed | Wherever found |
| Castilleja fraterna | No common name | 1 | Not Listed | Wherever found |
| Castilleja gleasonii | Mt. Gleason paintbrush | 1 | Not Listed | Wherever found |
| Castilleja lasiorhyncha | San Bernardino Mountains orthocarpus | 1 | Not Listed | Wherever found |
| Castilleja mendocinensis | Mendocino coast paintbrush | 1 | Not Listed | Wherever found |
| Castilleja parvula | Tushar indian paintbrush | 6 | Not Listed | Wherever found |
| Castilleja pilosa steenensis | Steen's mountain paintbrush | 1 | Not Listed | Wherever found |
| Castilleja revealii | Reveal indian paintbrush | 6 | Not Listed | Wherever found |
| Castilleja rubida | No common name | 1 | Not Listed | Wherever found |
| Castilleja salsuginosa | Monte Neva paintbrush | 8 | Not Listed | Wherever found |
| Castilleja sulphurea | White Mountains paintbrush | 2 | Not Listed | Wherever found |
| Castilleja uliginosa | Pitkin Marsh paintbrush | 1 | Not Listed | Wherever found |
| Castilleja wootonii | [Unnamed] indian paintbrush | 2 | Not Listed | Wherever found |
| cathartes aura | Turkey vulture | 7 | Not Listed | Wherever found |
| Catocala pretiosa pretiosa | Precious underwing | 5 | Not Listed | Wherever found |
| catostomus bernardini | Yaqui sucker | 2 | Not Listed | Wherever found |
| Catostomus clarkii | Desert sucker | 1 | Not Listed | Desert |
| Catostomus insignis | Sonora sucker | 2 | Not Listed | Wherever found |
| Catostomus latipinnis | Flannelmouth sucker | 2 | Not Listed | Wherever found |
| Catostomus occidentalis lacusanserinus | Goose Lake sucker | 1 | Not Listed | Wherever found |
| Catostomus rimiculus ssp. | Jenny Creek sucker | 1 | Not Listed | Wherever found |
| Catostomus snyderi | Klamath largescale sucker | 1 | Not Listed | Wherever found |
| Caulanthus simulans | Payson's jewelflower | 1 | Not Listed | Wherever found |
| Caulostramina jaegeri | Jaeger's caulostramina | 1 | Not Listed | Wherever found |
| Cavaticovelia aaa | Aaa water treader bug | 1 | Not Listed | Wherever found |
| Ceanothus arboreus glaber | No common name | 1 | Not Listed | Wherever found |
| Ceanothus confusus | Rincon ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus cuneatus rigidus | Monterey ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus cyaneus | Lakeside ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus divergens | Calistoga ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus foliosus vineatus | Vine Hill ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus gloriosus porrectus | Mt. Vision ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus hearstiorum | Hearst's ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus maritimus | Maritime california-lilac | 1 | Not Listed | Wherever found |
| Ceanothus masonii | Bolinas ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus sonomensis | Sonoma ceanothus | 1 | Not Listed | Wherever found |
| Ceanothus verrucosus | Wart-stemmed ceanothus | 1 | Not Listed | Wherever found |
| Cephaloziella obtusilobula | Roundleaf Liverwort | 4 | Not Listed | Wherever found |
| Ceraclea floridana | Florida ceraclean longhorn caddisfly | 4 | Not Listed | Wherever found |
| Ceraclea sp. | Lenat's ceraclean caddisfly | 4 | Not Listed | Wherever found |
| Ceraclea vertreesi | Vertrees's ceraclean caddisfly | 1 | Not Listed | Wherever found |
| Cerastium arvense villosissimum | Field, long-hairy chickweed | 5 | Not Listed | Wherever found |
| Ceratopsyche abella | Abellan hydropsyche caddisfly | 1 | Not Listed | Wherever found |
| Ceratopsyche etnieri | Buffalo Springs caddisfly | 4 | Not Listed | Wherever found |
| Cercyonis pegala ssp. | White River wood nymph | 1 | Not Listed | White River |
| Cereus gracilis simpsonii | Simpson's prickly-apple | 4 | Not Listed | Wherever found |
| certhia americana | Brown creeper | 7 | Not Listed | Wherever found |
| Cesonia irvingi | Key gnaphosid spider | 4 | Not Listed | Wherever found |
| Chaenactis cusickii | No common name | 1 | Not Listed | Wherever found |
| Chaetarthria leechi | Leech's chaetarthrian water scavenger beetle | 1 | Not Listed | Wherever found |
| chaetodipus fallax | Northwestern San Diego pocket mouse | 1 | Not Listed | Wherever found |
| Chaetopappa hersheyi | Mat leastdaisy | 2 | Not Listed | Wherever found |
| Chaetura vauxi | Vaux's swift | 6 | Not Listed | Wherever found |
| Chamaerhodos nuttallii keweenawensis | No common name | 3 | Not Listed | Wherever found |
| Chamaesyce arnottiana | `Akoko | 1 | Not Listed | Wherever found |
| Chamaesyce atrococca | `Akoko | 1 | Not Listed | Wherever found |
| Chamaesyce celastroides tomentella | `Akoko | 1 | Not Listed | Wherever found |
| Chamaesyce chaetocalyx triligulata | Three-tongued spurge | 2 | Not Listed | Wherever found |
| Chamaesyce cumulicola | No common name | 4 | Not Listed | Wherever found |
| Chamaesyce golondrina | Swallow spurge | 2 | Not Listed | Wherever found |
| Chamaesyce olowaluana | `Akoko | 1 | Not Listed | Wherever found |
| Chamaesyce platysperma | Flat-seeded spurge | 1 | Not Listed | Wherever found |
| Chamaesyce porteriana keyensis | Porter's, Key spurge | 4 | Not Listed | Wherever found |
| Chamaesyce porteriana porteriana | No common name | 4 | Not Listed | Wherever found |
| Chamaesyce porteriana scoparia | Porter's, spurge | 4 | Not Listed | Wherever found |
| Chamaesyce skottsbergii vaccinioides | `Akoko | 1 | Not Listed | Wherever found |
| Chamaesyce sparsiflora | `Akoko | 1 | Not Listed | Wherever found |
| Charina trivirgata | Rosy boa | 2 | Not Listed | Wherever found |
| Charina trivirgata roseofusca | Coastal rosy boa | 1 | Not Listed | Wherever found |
| Cheilolejeunea evansii | No common name | 4 | Not Listed | Wherever found |
| chelone cuthbertii | Cuthbert's turtlehead | 4 | Not Listed | Wherever found |
| Chenopodium cycloides | Sandhill goosefoot | 6 | Not Listed | Wherever found |
| Chersodromia hawaiiensis | Hawaiian chersodromian dance fly | 1 | Not Listed | Wherever found |
| Cheumatopsyche helma | Helma's net-spinning caddisfly | 5 | Not Listed | Wherever found |
| Cheumatopsyche morsei | Morse's net-spinning caddisfly | 4 | Not Listed | Wherever found |
| Cheumatopsyche vannotei | Vannote's net-spinning caddisfly | 5 | Not Listed | Wherever found |
| Chilostigma itascae | Headwater chilostigman caddisfly | 3 | Not Listed | Wherever found |
| Chitrella regina | Royal syarinid pseudoscorpion | 5 | Not Listed | Wherever found |
| Chlidonias niger | Black tern | 6 | Not Listed | Wherever found |
| Chloealtis aspasma | Siskiyou chloealtis grasshopper | 1 | Not Listed | Wherever found |
| Chloris texensis | Texas windmill grass | 2 | Not Listed | Wherever found |
| Chlorochroa belfragii | Belfragi's chlorochroan bug | 3 | Not Listed | Wherever found |
| Chlorochroa dismalia | Dismal Swamp chlorochroan bug | 5 | Not Listed | Wherever found |
| Chlorochroa rita | Santa Rita Mountains chlorochroan bug | 2 | Not Listed | Wherever found |
| Chlorogalum grandiflorum | Red Hills soaproot | 1 | Not Listed | Wherever found |
| Chlosyne leanira osoflaco | Oso Flaco patch butterfly | 1 | Not Listed | Wherever found |
| Choeronycteris mexicana | Mexican long-tongued bat | 2 | Not Listed | Wherever found |
| Choisya mollis | Santa Cruz star leaf | 2 | Not Listed | Wherever found |
| chordeiles acutipennis | Lesser nighthawk | 7 | Not Listed | Wherever found |
| Chorizanthe biloba immemora | San Benito spineflower | 1 | Not Listed | Wherever found |
| Chorizanthe cuspidata cuspidata | San Francisco Bay spineflower | 1 | Not Listed | Wherever found |
| Chorizanthe leptotheca | Ramona spineflower | 1 | Not Listed | Wherever found |
| Chorizanthe parryi parryi | Parry's spineflower | 1 | Not Listed | Wherever found |
| Chorizanthe polygonoides longispina | No common name | 1 | Not Listed | Wherever found |
| chorizanthe procumbens | Prostrate spineflower | 6 | Not Listed | Wherever found |
| Chorizanthe rectispina | One-awned spineflower | 1 | Not Listed | Wherever found |
| Chromolaena borinquensis | No common name | 4 | Not Listed | Wherever found |
| Chromolaena oteroi | No common name | 4 | Not Listed | Wherever found |
| Chrysophyllum cainito | No common name | 4 | Not Listed | Wherever found |
| Chrysopsis godfreyi | Godfrey's golden aster | 4 | Not Listed | Wherever found |
| Chrysopsis gossypina cruiseana | Cruise's golden aster | 4 | Not Listed | Wherever found |
| Chrysosplenium iowense | No common name | 3 | Not Listed | Wherever found |
| Chrysothamnus eremobius | No common name | 1 | Not Listed | Wherever found |
| Chrysothamnus molestus | No common name | 2 | Not Listed | Wherever found |
| Chrysothamnus nauseosus texensis | No common name | 2 | Not Listed | Wherever found |
| Chrysothamnus parryi hinckleyi | No common name | 2 | Not Listed | Wherever found |
| Cicindela arenicola | Idaho dunes tiger beetle | 1 | Not Listed | Wherever found |
| Cicindela cazieri | Cazier's tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela chlorocephala smythi | Smyth's tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela hirticollis gravida | Sandy beach tiger beetle | 1 | Not Listed | Wherever found |
| Cicindela latesignata obliviosa | Oblivious tiger beetle | 1 | Not Listed | Wherever found |
| Cicindela nevadica olmosa | Los Olmos tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela nigrocoerulea subtropica | Subtropical blue-black tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela obsoleta neojuvenilis | Neojuvenile tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela oregona maricopa | Maricopa tiger beetle | 2 | Not Listed | Wherever found |
| Cicindela tranquebarica ssp. | San Joaquin tiger beetle | 1 | Not Listed | Wherever found |
| Cicindela tranquebarica viridissima | Greenest tiger beetle | 1 | Not Listed | Wherever found |
| Cimicifuga elata | Tall bugbane | 1 | Not Listed | Wherever found |
| Cimicifuga rubifolia | No common name | 4 | Not Listed | Wherever found |
| Cincinnatia helicogyra | Crystal siltsnail | 4 | Not Listed | Wherever found |
| Cincinnatia vanhyningi | Seminole siltsnail | 4 | Not Listed | Wherever found |
| circus cyaneus | Northern harrier | 7 | Not Listed | Wherever found |
| Cirsium crassicaule | Slough thistle | 1 | Not Listed | Wherever found |
| Cirsium fontinale campylon | Mt. Hamilton thistle | 1 | Not Listed | Wherever found |
| Cirsium hillii | [Unnamed] thistle | 3 | Not Listed | Wherever found |
| Cirsium hydrophilum vaseyi | Mt. Tamalpais thistle | 1 | Not Listed | Wherever found |
| Cirsium longistylum | [Unnamed] thistle | 6 | Not Listed | Wherever found |
| Cirsium mohavense | Virgin thistle | 6 | Not Listed | Wherever found |
| Cirsium occidentale compactum | Compact cobweb thistle | 1 | Not Listed | Wherever found |
| Cirsium ownbeyi | Ownbey's thistle | 6 | Not Listed | Wherever found |
| Cirsium parryi mogollonicum | Mogollon thistle | 2 | Not Listed | Wherever found |
| Cirsium sp. | Sp. nov. ined. cirsium | 6 | Not Listed | R6 |
| Cladonia psoromica | Bluff Mountain Reindeer Lichen | 4 | Not Listed | Wherever found |
| claopodium whippleanum | Whipple's claopodium moss | 6 | Not Listed | Wherever found |
| Clarkia borealis arida | Arid northern clarkia | 1 | Not Listed | Wherever found |
| Clarkia concinna automixa | East Bay clarkia | 1 | Not Listed | Wherever found |
| Clarkia concinna raichei | Tomales clarkia | 1 | Not Listed | Wherever found |
| Clarkia mosquinii mosquinii | Mosquin's clarkia | 1 | Not Listed | Wherever found |
| Clarkia mosquinii xerophila | Enterprise clarkia | 1 | Not Listed | Wherever found |
| Clarkia rostrata | Beaked clarkia | 1 | Not Listed | Wherever found |
| Clarkia tembloriensis ssp. calientensis | Caliente clarkia | 1 | Not Listed | Wherever found |
| Clavicoccus erinaceus | Oahu abutilon clavicoccus mealybug | 1 | Not Listed | Wherever found |
| Clavicoccus tribulus | Oahu ke`oke`o clavicoccus mealybug | 1 | Not Listed | Wherever found |
| Claytonia lanceolata flava | No common name | 1 | Not Listed | Wherever found |
| Claytonia lanceolata peirsonii | Peirson's spring beauty | 1 | Not Listed | Wherever found |
| Claytonia virginica hammondiae | [Unnamed] spring-beauty | 5 | Not Listed | Wherever found |
| Clematis addisonii | Addison's virgin's bower | 5 | Not Listed | Wherever found |
| Clematis viticaulis | Millboro leatherflower | 5 | Not Listed | Wherever found |
| Cleome multicaulis | Slender spiderflower | 6 | Not Listed | Wherever found |
| Clethrionomys gapperi maurus | Kentucky red-backed vole | 4 | Not Listed | Wherever found |
| Clinopodium ashei | No common name | 4 | Not Listed | Wherever found |
| Cnemidophorus burti | Canyon spotted whiptail | 2 | Not Listed | Wherever found |
| Cnemidophorus dixoni | Gray-checkered whiptail | 2 | Not Listed | Wherever found |
| Cnemidophorus hyperythrus | Orange-throated whiptail | 1 | Not Listed | Wherever found |
| cnemidophorus hyperythrus ssp. beldingi | Belding's orange-throated whiptail | 6 | Not Listed | Wherever found |
| Cnemidophorus tigris multiscutatus | Coastal western whiptail | 1 | Not Listed | Wherever found |
| Coccyzus americanus ssp. occidentalis | No Common Name | 8 | Not Listed | Wherever found |
| Coccyzus erythropthalmus | Black-billed Cuckoo | 6 | Not Listed | Wherever found |
| Coelorachis tuberculosa | No common name | 4 | Not Listed | Wherever found |
| Coelus globosus | Globose dune beetle | 1 | Not Listed | Wherever found |
| Coelus pacificus | Channel Islands dune beetle | 1 | Not Listed | Wherever found |
| Coenonycha clementina | San Clemente Island coenonycha beetle | 1 | Not Listed | Wherever found |
| Colaptes chrysoides | Gilded Flicker | 6 | Not Listed | Wherever found |
| Coleonyx switaki | Barefoot gecko | 1 | Not Listed | Wherever found |
| Coleonyx variegatus abbotti | San Diego banded gecko | 1 | Not Listed | Wherever found |
| Coleophora leucochrysella | Chestnut casebearer moth | 5 | Not Listed | Wherever found |
| Coleotichus blackburniae | Koa shield bug | 1 | Not Listed | Wherever found |
| Collinsia antonina | No common name | 1 | Not Listed | Wherever found |
| collinsia multicolor | San Francisco collinsia | 8 | Not Listed | Wherever found |
| Collomia mazama | Crater Lake collomia | 1 | Not Listed | Wherever found |
| Collomia renacta | No common name | 1 | Not Listed | Wherever found |
| Colubrina stricta | Comal snakewood | 2 | Not Listed | Wherever found |
| Comarostaphylis diversifolia diversifolia | Summer-holly | 1 | Not Listed | Wherever found |
| Condalia hookeri edwardsiana | Edwards' brasil | 2 | Not Listed | Wherever found |
| Conepatus mesoleucus figginsi | Colorado hog-nosed skunk | 6 | Not Listed | Wherever found |
| Conepatus mesoleucus telmalestes | Big Thicket hog-nosed skunk | 2 | Not Listed | Wherever found |
| Conioselinum mexicanum | Hemlock, Mexican parsley | 2 | Not Listed | Wherever found |
| Conostegia rufescens | No common name | 4 | Not Listed | Wherever found |
| Conradina grandiflora | [Unnamed] rosemary | 4 | Not Listed | Wherever found |
| Contopus cooperi | Olive-sided flycatcher | 7 | Not Listed | Wherever found |
| convolvulus equitans | Clay bindweed | 6 | Not Listed | Wherever found |
| Convolvulus equitans | Small-flowered morning-glory | 8 | Not Listed | Wherever found |
| Cophura hurdi | Antioch cophuran robberfly | 1 | Not Listed | Wherever found |
| Copris gopheri | Copris tortoise commensal scarab | 4 | Not Listed | Wherever found |
| Cordia wagnerorum | No common name | 4 | Not Listed | Wherever found |
| Cordylanthus maritimus palustris | Northcoast birds-beak | 1 | Not Listed | Wherever found |
| Cordylanthus mollis hispidus | Hispid birds-beak | 1 | Not Listed | Wherever found |
| Cordylanthus orcuttianus | Orcutt's bird's-beak | 1 | Not Listed | Wherever found |
| Cordylanthus rigidus littoralis | Seaside birds-beak | 1 | Not Listed | Wherever found |
| Cordylanthus tecopensis | Tecopa bird's-beak | 1 | Not Listed | Wherever found |
| Cordylanthus tenuis barbatus | Fresno County bird's-beak | 1 | Not Listed | Wherever found |
| Cordylanthus tenuis pallescens | Pallid birds-beak | 1 | Not Listed | Wherever found |
| Coregonus kiyi | Kiyi | 3 | Not Listed | Wherever found |
| Coregonus reighardi | Shortnose cisco | 3 | Not Listed | Wherever found |
| Coregonus zenithicus | Shortjaw cisco | 3 | Not Listed | Wherever found |
| Coreopsis hamiltonii | Mt. Hamilton coreopsis | 1 | Not Listed | Wherever found |
| Coreopsis intermedia | Golden wave tickseed | 4 | Not Listed | Wherever found |
| Corvomeyenia carolinensis | Carolina sponge | 4 | Not Listed | Wherever found |
| Corydalis aquae-gelidae | No common name | 1 | Not Listed | Wherever found |
| Coryphantha chaffeyi | Chaffey's cory cactus | 2 | Not Listed | Wherever found |
| Coryphantha dasyacantha dasyacantha | No common name | 2 | Not Listed | Wherever found |
| Coryphantha duncanii | Duncan's cory cactus | 2 | Not Listed | Wherever found |
| Coryphantha recurvata | Santa Cruz beehive cactus | 2 | Not Listed | Wherever found |
| Coryphantha sulcata nickelsiae | Nickel's cory cactus | 2 | Not Listed | Wherever found |
| Coryphantha vivipara alversonii | Alverson's foxtail cactus | 1 | Not Listed | Wherever found |
| Cottus asperrimus | Rough sculpin | 1 | Not Listed | Wherever found |
| Cottus bairdii | Malheur mottled sculpin | 1 | Not Listed | Wherever found |
| Cottus leiopomus | Wood River sculpin | 1 | Not Listed | Wherever found |
| Cottus marginatus | Margined sculpin | 1 | Not Listed | Wherever found |
| Cottus sp. | Bluestone sculpin | 5 | Not Listed | Wherever found |
| Cottus tenuis | Slender sculpin | 1 | Not Listed | Wherever found |
| Coturnicops noveboracensis | Yellow Rail | 6 | Not Listed | Wherever found |
| Coursetia glabella | No common name | 2 | Not Listed | Wherever found |
| Crambus daeckeellus | Daecke's pyralid moth | 5 | Not Listed | Wherever found |
| Crangonyx dearolfi | Dearolf's cave amphipod | 5 | Not Listed | Wherever found |
| Crataegus harbisonii | [Unnamed] haw | 4 | Not Listed | Wherever found |
| Crataegus oreophila | Balsam Mountain Hawthorn | 4 | Not Listed | |
| Crataegus triflora | No common name | 4 | Not Listed | Wherever found |
| Crataegus warneri | Warner hawthorn | 2 | Not Listed | Wherever found |
| Crenichthys baileyi thermophilus | Mormon White River Springfish | 1 | Not Listed | Wherever found |
| Crotalus cerastes | sidewinder | 6 | Not Listed | Wherever found |
| Crotalus mitchellii | Speckled rattlesnake | 6 | Not Listed | Wherever found |
| Crotalus ruber ruber | Northern red diamond rattlesnake | 1 | Not Listed | Wherever found |
| crotalus scutulatus ssp. scutulatus | Mojave green rattlesnake | 2 | Not Listed | Wherever found |
| Croton alabamensis alabamensis | Alabama croton | 4 | Not Listed | Wherever found |
| Croton fishlockii | No common name | 4 | Not Listed | Wherever found |
| Cryptantha aperta | Grand Junction catseye | 6 | Not Listed | Wherever found |
| Cryptantha cinerea arenicola | No common name | 6 | Not Listed | Wherever found |
| Cryptantha creutzfeldtii | No common name | 6 | Not Listed | Wherever found |
| Cryptantha crinita | Silky cryptantha | 1 | Not Listed | Wherever found |
| Cryptantha insolita | [Unnamed] catseye | 1 | Not Listed | Wherever found |
| Cryptantha rollinsii | No common name | 6 | Not Listed | Wherever found |
| Cryptantha roosiorum | Bristlecone catseye | 1 | Not Listed | Wherever found |
| Cryptantha shackletteana | [Unnamed] catseye | 7 | Not Listed | Wherever found |
| Cryptantha sobolifera | Schoolcraft's cryptantha | 1 | Not Listed | Wherever found |
| Cryptantha subcapitata | No common name | 6 | Not Listed | Wherever found |
| Cryptantha welshii | Welsh's cryptantha | 1 | Not Listed | Wherever found |
| Cryptochia denningi | Denning's cryptic caddisfly | 1 | Not Listed | Wherever found |
| Cryptochia excella | Kings Canyon cryptochian caddisfly | 1 | Not Listed | Wherever found |
| Cryptochia neosa | Blue Mountains cryptochian caddisfly | 1 | Not Listed | Wherever found |
| Cryptochia shasta | Confusion caddisfly | 1 | Not Listed | Wherever found |
| Cryptomastix magnidentata | Mission Creek oregonian | 1 | Not Listed | Wherever found |
| Ctenonotus cooki | Cook's anole | 4 | Not Listed | Wherever found |
| Cuphea aspera | No common name | 4 | Not Listed | Wherever found |
| Cupressus forbesii | Tecate cypress | 1 | Not Listed | Wherever found |
| Cupressus goveniana pigmaea | Mendocino cypress | 1 | Not Listed | Wherever found |
| Cupressus macrocarpa | Monterey cypress | 1 | Not Listed | Wherever found |
| Cuscuta attenuata | Slender dodder | 2 | Not Listed | Wherever found |
| Cuscuta harperi | Harper's dodder | 4 | Not Listed | Wherever found |
| Cuscuta warneri | Warner's dodder | 6 | Not Listed | Wherever found |
| Cusickiella quadricostata | Bodie Hills draba | 1 | Not Listed | Wherever found |
| Cyanea leptostegia | Giant koke`e | 1 | Not Listed | Wherever found |
| Cyanea longissima | Haha | 1 | Not Listed | Wherever found |
| Cycleptus elongatus | Blue sucker | 3 | Not Listed | Wherever found |
| Cyclocephala miamiensis | Miami roundhead scarab | 4 | Not Listed | Wherever found |
| Cyclocosmia torreya | Torreya trap-door spider | 4 | Not Listed | Wherever found |
| Cycloptilum irregularis | Keys scaly cricket | 4 | Not Listed | Wherever found |
| Cygnus buccinator | Trumpeter swan | 6 | Not Listed | Wherever found |
| Cylindrocolea andersonii | [Unnamed] liverwort | 4 | Not Listed | Wherever found |
| Cymbiodyta arizonica | Chiricahua water scavenger beetle | 2 | Not Listed | Wherever found |
| Cymocythere clavata | Oconee crayfish ostracod | 4 | Not Listed | Wherever found |
| Cymopterus acaulis higginsii | Higgins biscuitroot | 6 | Not Listed | Wherever found |
| Cymopterus davisii | No common name | 1 | Not Listed | Wherever found |
| Cymopterus douglassii | No common name | 1 | Not Listed | Wherever found |
| Cymopterus goodrichii | No common name | 1 | Not Listed | Wherever found |
| Cymopterus megacephalus | No common name | 2 | Not Listed | Wherever found |
| Cymopterus ripleyi saniculoides | No common name | 1 | Not Listed | Wherever found |
| Cynanchum wigginsii | No common name | 2 | Not Listed | Wherever found |
| Cynomys ludovicianus arizonensis | Arizona black-tailed prairie dog | 2 | Not Listed | Wherever found |
| Cyperus grayoides | Umbrella sedge | 3 | Not Listed | Wherever found |
| Cyperus louisianensis | [Unnamed] sedge | 4 | Not Listed | Wherever found |
| Cyperus onerosus | Flat dune sedge | 2 | Not Listed | Wherever found |
| Cyperus rockii | No common name | 1 | Not Listed | Wherever found |
| Cyperus urbanii | Urban's flatsedge | 4 | Not Listed | Wherever found |
| Cyprinella callisema | Ocmulgee shiner | 4 | Not Listed | Wherever found |
| Cyprinella proserpina | Proserpine shiner | 2 | Not Listed | Wherever found |
| Cyprinodon | Palomas pupfish | 2 | Not Listed | Wherever found |
| Cyprinodon eximius | Conchos pupfish | 2 | Not Listed | Wherever found |
| Cyprinodon nevadensis shoshone | Shoshone pupfish | 1 | Not Listed | Wherever found |
| Cypripedium fasciculatum | Clustered lady's-slipper | 1 | Not Listed | Wherever found |
| Cypripedium kentuckiense | [Unnamed] lady's-slipper | 4 | Not Listed | Wherever found |
| Cypseloides niger | Black Swift | 1 | Not Listed | Wherever found |
| Cyrtandra biserrata | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra halawensis | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra kealiae | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra lydgatei | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra macrocalyx | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra pickeringii | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra pruinosa | Ha`iwale | 1 | Not Listed | Wherever found |
| Cyrtandra sandwicensis | Ha`iwale | 1 | Not Listed | Wherever found |
| Dactylocythere isabelae | [Unnamed] ostracod | 4 | Not Listed | Wherever found |
| Dactylocythere peedeensis | Pee Dee crayfish ostracod | 4 | Not Listed | Wherever found |
| Dactylocythere prinsi | Whitewater crayfish ostracod | 4 | Not Listed | Wherever found |
| Daihinibaenetes arizonensis | Arizona giant sand treader cricket | 2 | Not Listed | Wherever found |
| Dalea flavescens epica | Hole-In-The-Rock prairie-clover | 6 | Not Listed | Wherever found |
| Dalea reverchonii | Comanche-peak prairie-clover | 2 | Not Listed | Wherever found |
| Dalea sabinalis | Sabinal prairie-clover | 2 | Not Listed | Wherever found |
| Decodes stevensi | Stevens' tortricid moth | 6 | Not Listed | Wherever found |
| Dedeckera eurekensis | July gold | 1 | Not Listed | Wherever found |
| Deinocossonus nesiotes | Oahu nesiotes weevil | 1 | Not Listed | Wherever found |
| Deinomimesa hawaiiensis | Hawaiian deinomimesan sphecid wasp | 1 | Not Listed | Wherever found |
| Deinomimesa punae | Puna deinomimesan sphecid wasp | 1 | Not Listed | Wherever found |
| Delphinium californicum interius | Hospital Canyon larkspur | 1 | Not Listed | Wherever found |
| Delphinium exaltatum | Tall larkspur | 4 | Not Listed | Wherever found |
| Delphinium hesperium cuyamacae | Cuyamaca larkspur | 1 | Not Listed | Wherever found |
| Delphinium hutchinsonae | Hutchinson's delphinium | 1 | Not Listed | Wherever found |
| Delphinium leucophaeum | Larkspur | 1 | Not Listed | Wherever found |
| Delphinium nuttallii ssp. nuttallii | Willamette Valley larkspur | 1 | Not Listed | Wherever found |
| Delphinium parryi blochmaniae | Dune larkspur | 1 | Not Listed | Wherever found |
| Delphinium recurvatum | Recurved larkspur | 1 | Not Listed | Wherever found |
| Dendrocygna arborea | West Indian whistling duck | 4 | Not Listed | Puerto Rico |
| Dendrocygna bicolor | Fulvous whistling duck | 1 | Not Listed | Wherever found |
| Dendrographa leucophaea | No common name | 1 | Not Listed | Wherever found |
| Dendroica dominica stoddardi | Stoddard's yellow-throated warbler | 4 | Not Listed | Wherever found |
| dendroica petechia ssp. brewsteri | Yellow warbler | 7 | Not Listed | Wherever found |
| Dendroica petechia ssp. sonorana | Sonoran Yellow Warbler | 6 | Not Listed | Wherever found |
| Dendromecon rigida rhamnoides | Island tree poppy | 1 | Not Listed | Wherever found |
| Dendromecon rigida ssp. harfordii | Channel Island tree poppy | 1 | Not Listed | Wherever found |
| Dendropemon sintenisii | Hicaquillo | 4 | Not Listed | Wherever found |
| Deronectes neomexicana | Bonita diving beetle | 2 | Not Listed | Wherever found |
| Deropristus deroderus | Haleakala deropristus ground beetle | 1 | Not Listed | Wherever found |
| Desmodium humifusum | Ground-spreading tick-trefoil | 5 | Not Listed | Wherever found |
| Desmodium lindheimeri | Lindheimer's tickseed | 2 | Not Listed | Wherever found |
| Desmognathus brimleyorum | Ouachita dusky salamander | 4 | Not Listed | Wherever found |
| Desmognathus wrighti | Pygmy salamander | 4 | Not Listed | Wherever found |
| Desmona bethula | Amphibious caddisfly | 1 | Not Listed | Wherever found |
| Desmopachria cenchramis | Fig seed diving beetle | 4 | Not Listed | Wherever found |
| Diacyclops jeanneli putei | Carolina well diacyclops | 4 | Not Listed | Wherever found |
| diadophis punctatus | Ringneck snake | 2 | Not Listed | Wherever found |
| Diadophis punctatus modestus | San Bernardino ringneck snake | 1 | Not Listed | Wherever found |
| Diadophis punctatus similis | San Diego ringneck snake | 1 | Not Listed | Wherever found |
| Diastole matafaoi | Mt. Matafao different snail | 1 | Not Listed | Wherever found |
| Diastole schmeltziana | [Unnamed] snail | 1 | Not Listed | Wherever found |
| dicamptodon tenebrosus | Pacific giant salamander | 6 | Not Listed | Wherever found |
| Dicerandra radfordiana | [Unnamed] mint | 4 | Not Listed | Wherever found |
| Dichanthelium aciculare var. aciculare | No common name | 4 | Not Listed | Wherever found |
| Dichanthelium acuminatum acuminatum | The Geysers panic grass | 1 | Not Listed | Wherever found |
| Dichanthelium nudicaule | No common name | 4 | Not Listed | Wherever found |
| Dicliptera krugii | No common name | 4 | Not Listed | Wherever found |
| Dicranopselaphus variegatus | Variegated false water penny | 3 | Not Listed | Wherever found |
| dicranoweisia crispula | Dicranoweisia moss | 6 | Not Listed | Wherever found |
| Digitaria floridana | No common name | 4 | Not Listed | Wherever found |
| Digitaria gracillima | No common name | 4 | Not Listed | Wherever found |
| Dionda nigrotaeniata | Guadalupe roundnose Minnow | 2 | Not Listed | Wherever found |
| Diplacus clevelandii | Cleveland's bush monkeyflower | 8 | Not Listed | Wherever found |
| Diplectrona californica | California diplectronan caddisfly | 1 | Not Listed | Wherever found |
| Diplectrona rossi | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Dipodomys californicus eximius | Marysville California kangaroo rat | 1 | Not Listed | Wherever found |
| Dipodomys heermanni berkleyensis | Berkeley kangaroo rat | 8 | Not Listed | Wherever found |
| Dipodomys heermanni dixoni | Merced kangaroo rat | 1 | Not Listed | Wherever found |
| Dipodomys merriami collinus | Earthquake Merriam's kangaroo rat | 1 | Not Listed | Wherever found |
| Dipodomys merriami frenatus | Virgin Merriam's kangaroo rat | 6 | Not Listed | Wherever found |
| Dipodomys microps alfredi | Gunnison Island kangaroo rat | 6 | Not Listed | Wherever found |
| Dipodomys microps leucotis | Marble Canyon kangaroo rat | 2 | Not Listed | Wherever found |
| Dipodomys microps russeolus | Dolphin Island kangaroo rat | 6 | Not Listed | Wherever found |
| Dipodomys nitratoides brevinasus | Short-nosed kangaroo rat | 1 | Not Listed | Wherever found |
| Dipodomys ordii cineraceus | Dolphin Island ord's kangaroo rat | 6 | Not Listed | Wherever found |
| dipodomys simulans | Dulzura kangaroo rat | 6 | Not Listed | Wherever found |
| dipsosaurus dorsalis | Desert iguana | 2 | Not Listed | Wherever found |
| Discus marmorensis | Marbled disc | 1 | Not Listed | Wherever found |
| Discus shemeki cockerelli | Cockerell's striate disc | 6 | Not Listed | Wherever found |
| Disenochus micantipennis | Kauai disenochus ground beetle | 1 | Not Listed | Wherever found |
| Dissanthelium californicum | California dissanthelium | 1 | Not Listed | Wherever found |
| Distoleon perjerus | Molokai antlion | 1 | Not Listed | Wherever found |
| Ditaxis serrata | California ditaxis | 1 | Not Listed | Wherever found |
| Dodecatheon austrofrigidum | Tundra shootingstar | 1 | Not Listed | Wherever found |
| Dolania americana | American sandburrowing mayfly | 4 | Not Listed | Wherever found |
| Dosilia palmeri | Oklawaha sponge | 4 | Not Listed | Wherever found |
| Douglasia idahoensis | No common name | 1 | Not Listed | Wherever found |
| Draba arida | No common name | 1 | Not Listed | Wherever found |
| Draba asterophora macrocarpa | Cup Lake draba | 1 | Not Listed | Wherever found |
| Draba carnosula | Mt. Eddy draba | 1 | Not Listed | Wherever found |
| Draba crassifolia nevadensis | Dolomite draba | 1 | Not Listed | Wherever found |
| Draba jaegeri | No common name | 1 | Not Listed | Wherever found |
| Draba murrayi | No common name | 7 | Not Listed | Wherever found |
| Draba oreibata serpentina | No common name | 1 | Not Listed | Wherever found |
| Draba paucifructa | No common name | 1 | Not Listed | Wherever found |
| Draba pectinipila | No common name | 6 | Not Listed | Wherever found |
| Draba smithii | No common name | 6 | Not Listed | Wherever found |
| Draba sobolifera | Stolon whitlow-grass | 6 | Not Listed | Wherever found |
| Draba standleyi | Standley whitlow-grass | 2 | Not Listed | Wherever found |
| Draba trichocarpa | Stanley whitlow-grass | 1 | Not Listed | Wherever found |
| Draba yukonensis | No common name | 7 | Not Listed | Wherever found |
| Dracontium polyphyllum | No common name | 4 | Not Listed | Wherever found |
| Drosophila lanaiensis | Lanai pomace fly | 1 | Not Listed | Wherever found |
| Dryobius sexnotatus | Sixbanded long-horned beetle | 4 | Not Listed | Wherever found |
| dryocopus pileatus | Pileated woodpecker | 6 | Not Listed | Wherever found |
| Dubautia arborea | Na`ena`e | 1 | Not Listed | Wherever found |
| Dubautia knudsenii filiformis | Na`ena`e | 1 | Not Listed | Wherever found |
| Dubautia microcephala | Na`ena`e | 1 | Not Listed | Wherever found |
| Dubautia sherffiana | Sherff railliardia | 1 | Not Listed | Wherever found |
| Dubiraphia brunnescens | Brownish dubiraphian riffle beetle | 1 | Not Listed | Wherever found |
| Dubiraphia giulianii | Giuliani's dubiraphian riffle beetle | 1 | Not Listed | Wherever found |
| Dubiraphia parva | Little riffle beetle | 4 | Not Listed | Wherever found |
| Dubiraphia robusta | Robust dubiraphian riffle beetle | 3 | Not Listed | Wherever found |
| Dudleya abramsii affinis | San Bernardino Mountains dudleya | 1 | Not Listed | Wherever found |
| Dudleya abramsii bettinae | San Luis serpentine dudleya | 1 | Not Listed | Wherever found |
| Dudleya attentuata orcuttii | Orcutt's dudleya | 1 | Not Listed | Wherever found |
| Dudleya blochmaniae blochmaniae | Short-leaved dudleya | 1 | Not Listed | Wherever found |
| Dudleya candelabrum | Candleholder dudleya | 1 | Not Listed | Wherever found |
| Dudleya cymosa costifolia | Pierpoint Springs liveforever | 1 | Not Listed | Wherever found |
| Dudleya cymosa crebrifolia | San Gabriel River dudleya | 1 | Not Listed | Wherever found |
| Dudleya multicaulis | Many-stemmed liveforever | 1 | Not Listed | Wherever found |
| Dudleya saxosa saxosa | Panamint dudleya | 1 | Not Listed | Wherever found |
| Dudleya variegata | Variegated dudleya | 1 | Not Listed | Wherever found |
| Dudleya virens | Green liveforever | 1 | Not Listed | Wherever found |
| dudleya virens ssp. insularis | Island green dudleya | 1 | Not Listed | Wherever found |
| Dumontia oregonensis | hairy water flea | 1 | Not Listed | Wherever found |
| Eanus hatchi | Hatch's click beetle | 1 | Not Listed | Wherever found |
| Ecclisomyia bilera | King's Creek ecclisomyian caddisfly | 1 | Not Listed | Wherever found |
| Echeandia chandleri | Lilia de los llanos | 2 | Not Listed | Wherever found |
| Echinocereus engelmannii howei | Howe's hedgehog cactus | 1 | Not Listed | Wherever found |
| Echinocereus engelmannii munzii | Munz's hedgehog cactus | 1 | Not Listed | Wherever found |
| Echinocereus papillosus angusticeps | Small papillosus | 2 | Not Listed | Wherever found |
| Echinocereus viridiflorus cylindricus | Golden-spined hedgehog cactus | 2 | Not Listed | Wherever found |
| Echinodorus tenellus | No common name | 6 | Not Listed | Wherever found |
| Echinomastus erectocentrus erectocentrus | No common name | 2 | Not Listed | Wherever found |
| Ectemnius bidecoratus | Bidecoratus sphecid wasp | 1 | Not Listed | Wherever found |
| Ectemnius curtipes | Short-foot ectemnius sphecid wasp | 1 | Not Listed | Wherever found |
| Ectemnius fulvicrus | Brown cross ectemnius sphecid wasp | 1 | Not Listed | Wherever found |
| Ectemnius giffardi | Giffard's ectemnius sphecid wasp | 1 | Not Listed | Wherever found |
| Ectemnius haleakalae | Haleakala ectemnius sphecid wasp | 1 | Not Listed | Wherever found |
| Ectemnius rubrocaudatus | Redtail sphecid wasp | 1 | Not Listed | Wherever found |
| Ectodemia castaneae | American chestnut nepticulid moth | 5 | Not Listed | Wherever found |
| Ectodemia phleophaga | Phleophagan chestnut nepticulid moth | 5 | Not Listed | Wherever found |
| Efferia antiochi | Antioch efferian robberfly | 1 | Not Listed | Wherever found |
| Egretta rufescens | Reddish egret | 4 | Not Listed | Wherever found |
| Elanoides forficatus | Swallow-tailed Kite | 4 | Not Listed | Wherever found |
| Elanus caeruleus | Black-winged kite | 6 | Not Listed | Wherever found |
| Elanus leucurus | White-tailed Kite | 1 | Not Listed | Wherever found |
| Eleocharis wolfii | No common name | 3 | Not Listed | Wherever found |
| Eleutherodactylus eneidae | Mottled coqui | 4 | Not Listed | Wherever found |
| Eleutherodactylus karlschmidti | Web-footed coqui | 4 | Not Listed | Wherever found |
| Elimia albanyensis | Black-crest elima | 4 | Not Listed | Wherever found |
| Elimia aterina | Coal elimia | 4 | Not Listed | Wherever found |
| Elimia boykiniana | Flaxen elimia | 4 | Not Listed | Wherever found |
| Elimia capillaris | Spindle elimia | 4 | Not Listed | Wherever found |
| Elimia fascinans | Banded elimia | 4 | Not Listed | Wherever found |
| Elimia haysiana | Silt elimia | 4 | Not Listed | Wherever found |
| Elimia hydei | Gladiator elimia | 4 | Not Listed | Wherever found |
| Elimia interrupta | Knotty elimia | 4 | Not Listed | Wherever found |
| Elimia interveniens | Slowwater elimia | 4 | Not Listed | Wherever found |
| Elimia porrecta | Nymph elimia | 4 | Not Listed | Wherever found |
| Elimia pybasi | Spring elimia | 4 | Not Listed | Wherever found |
| Elimia strigosa | Brook elimia | 4 | Not Listed | Wherever found |
| Elimia troostiana | Mossy elimia | 4 | Not Listed | Wherever found |
| Elimia varians | Puzzle elimia | 4 | Not Listed | Wherever found |
| Elliptio judithae | Neuse slabshell | 4 | Not Listed | Wherever found |
| Elliptio nigella | Winged spike | 4 | Not Listed | Wherever found |
| Elliptio shepardiana | Altamaha lance | 4 | Not Listed | Wherever found |
| Elliptio sp. | Waccamaw lance | 4 | Not Listed | Wherever found |
| Elliptio waccamawensis | Waccamaw spike | 4 | Not Listed | Wherever found |
| Elliptio waltoni | Florida lance | 4 | Not Listed | Wherever found |
| Elodea schweinitzii | Schweinitz's waterweed | 5 | Not Listed | Wherever found |
| Elymus svensonii | No common name | 4 | Not Listed | Wherever found |
| Emballonura semicaudata semicaudata | Sheath-tailed Bat | 1 | Not Listed | Wherever found |
| Empicoris pulchrus | Pulchrus thread bug | 1 | Not Listed | Wherever found |
| Empidonax fulvifrons | Buff-breasted Flycatcher | 9 | Not Listed | Wherever found |
| Empidonax traillii | Willow Flycatcher | 7 | Not Listed | Wherever found |
| Empidonax traillii brewsteri | Little willow flycatcher | 1 | Not Listed | Wherever found |
| Empidonax virescens | Acadian Flycatcher | 6 | Not Listed | Wherever found |
| Enallagma laterale | Lateral bluet | 5 | Not Listed | Wherever found |
| Enceliopsis covillei | Panamint daisy | 1 | Not Listed | Wherever found |
| Encyclia kranzlinii | No common name | 4 | Not Listed | Wherever found |
| Ensatina eschscholtzii croceator | Yellow-blotched ensatina | 1 | Not Listed | Wherever found |
| Ensatina eschscholtzii klauberi | Large-blotched ensatina | 1 | Not Listed | Wherever found |
| Eobrachycentrus gelidae | Mt. Hood primitive brachycentrid caddisfly | 1 | Not Listed | Wherever found |
| Eopenthes ambiguus | Ambiguous eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes arduus | Arduous eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes auratus | Golden eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes celatus | Hidden eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes cognatus | Cognatus eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes debilis | Weak eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes deceptor | Deceptive eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes funebris | Death eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes germanus | Germanus eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes kauaiensis | Kauai eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes muticus | Muticus eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes pallipes | Pallipes eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes plebeius | Common eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes politus | Politus eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes tarsalis | Tarsalis eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes tinctus | Tinged eopenthes click beetle | 1 | Not Listed | Wherever found |
| Eopenthes unicolor | Unicolored eopenthes click beetle | 1 | Not Listed | Wherever found |
| Ephemera triplex | West Virginia burrowing mayfly | 5 | Not Listed | Wherever found |
| Ephemerella argo | Argo ephemerellan mayfly | 3 | Not Listed | Wherever found |
| Ephydatia subtilis | Kissimmee sponge | 4 | Not Listed | Wherever found |
| Epilobium nevadense | Nevada willowherb | 6 | Not Listed | Wherever found |
| Epilobium oreganum | Oregon fireweed | 1 | Not Listed | Wherever found |
| eptesicus fuscus | Big brown bat | 6 | Not Listed | Wherever found |
| Eragrostis leptostachya | No common name | 1 | Not Listed | Wherever found |
| Eragrostis pectinacea | Sanibel love grass | 4 | Not Listed | Wherever found |
| Eremarionta immaculata | White desertsnail | 1 | Not Listed | Wherever found |
| Eremarionta millepalmarum | Thousand Palms desertsnail | 1 | Not Listed | Wherever found |
| Eremarionta morongoana | Morongo desertsnail | 1 | Not Listed | Wherever found |
| Eriastrum brandegeeae | Brandegee eriastrum | 1 | Not Listed | Wherever found |
| Ericameria crispa | No common name | 6 | Not Listed | Wherever found |
| Ericameria fasciculata | Eastwood's goldenweed | 1 | Not Listed | Wherever found |
| Ericameria nauseosa var. iridis | No common name | 6 | Not Listed | Wherever found |
| Ericameria zionis | No common name | 6 | Not Listed | Wherever found |
| Erigeron anchana | Mogollon fleabane | 2 | Not Listed | Wherever found |
| Erigeron canaanii | No common name | 6 | Not Listed | Wherever found |
| Erigeron carringtonae | No common name | 6 | Not Listed | Wherever found |
| Erigeron cronquistii | Cronquist daisy | 6 | Not Listed | Wherever found |
| Erigeron heligraphicus | Pinalenos fleabane | 2 | Not Listed | Wherever found |
| Erigeron howellii | Howell's fleabane | 1 | Not Listed | Wherever found |
| Erigeron kachinensis | Kachina daisy | 6 | Not Listed | Wherever found |
| Erigeron lackshewitz | No common name | 6 | Not Listed | Wherever found |
| Erigeron latus | [Unnamed] fleabane | 1 | Not Listed | Wherever found |
| Erigeron maguirei harrisonii | No common name | 6 | Not Listed | Wherever found |
| Erigeron mancus | Depauperate daisy | 6 | Not Listed | Wherever found |
| Erigeron multiceps | Kern River daisy | 1 | Not Listed | Wherever found |
| Erigeron oreganus | Gorge fleabane | 1 | Not Listed | Wherever found |
| Erigeron ovinus | No common name | 1 | Not Listed | Wherever found |
| Erigeron pulchellus tolsteadii | No common name | 3 | Not Listed | Wherever found |
| Erigeron salmonensis | No common name | 1 | Not Listed | Wherever found |
| Erigeron sionis | No common name | 6 | Not Listed | Wherever found |
| Erigeron sivinskii | No common name | 2 | Not Listed | Wherever found |
| Erigeron sp. | Sp. nov. ined. erigeron | 6 | Not Listed | Wherever found |
| Erigeron supplex | Supple daisy | 1 | Not Listed | Wherever found |
| Erigeron untermannii | No common name | 6 | Not Listed | Wherever found |
| Erigeron versicolor | Sonora fleabane | 2 | Not Listed | Wherever found |
| Eriochloa michauxii simpsonii | No common name | 4 | Not Listed | Wherever found |
| Eriogonum alpinum | Trinity buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum anemophilum | [Unnamed] buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum apachense | Apache wild-buckwheat | 2 | Not Listed | Wherever found |
| Eriogonum aretioides | Widstoe wild-buckwheat | 6 | Not Listed | Wherever found |
| Eriogonum bifurcatum | Forked buckwheat | 8 | Not Listed | Wherever found |
| Eriogonum breedlovei breedlovei | Piute buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum butterworthianum | Butterworth's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum capillare | San Carlos wild-buckwheat | 2 | Not Listed | Wherever found |
| Eriogonum chrysops | Golden buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum crocatum | Conejo buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum cusickii | Cusick's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum eremicola | Wild Rose Canyon buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum ericifolium thornei | Thorne's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum flavum aquilinum | [Unnamed] wild-buckwheat | 7 | Not Listed | Wherever found |
| Eriogonum giganteum compactum | Santa Barbara Island buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum giganteum formosum | San Clemente Island buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum grande rubescens | Large red buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum grande timorum | San Nicolas Island buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum holmgrenii | Holmgren's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum intrafractum | Jointed buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum kennedyi pinicola | Cache Peak buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum lagopus | No common name | 6 | Not Listed | Wherever found |
| Eriogonum lewisii | No common name | 1 | Not Listed | Wherever found |
| Eriogonum lobbii robustum | No common name | 1 | Not Listed | Wherever found |
| Eriogonum longifolium harperi | No common name | 4 | Not Listed | Wherever found |
| Eriogonum meledonum | [Unnamed] buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum microthecum johnstonii | Johnston's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum microthecum panamintense | Panamint Mountains buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum nervulosum | Snow Mountain buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum nudum murinum | Mouse buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum prociduum | Prostrate buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum ripleyi | Ripley wild-buckwheat | 2 | Not Listed | Wherever found |
| Eriogonum suffruticosum | Bushy wild-buckwheat | 2 | Not Listed | Wherever found |
| Eriogonum temblorense | Temblor buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum thompsonae atwoodii | Thompson, Atwood's wild-buckwheat | 2 | Not Listed | Wherever found |
| Eriogonum twisselmannii | Twisselmann's buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum umbellatum torreyanum | Donner Pass buckwheat | 1 | Not Listed | Wherever found |
| Eriogonum viscidulum | [Unnamed] buckwheat | 8 | Not Listed | Wherever found |
| Eriogonum visheri | No common name | 6 | Not Listed | Wherever found |
| Eriophyllum lanatum hallii | Ft. Tejon wooly-sunflower | 1 | Not Listed | Wherever found |
| Eriophyllum mohavense | Barstow wooly-sunflower | 1 | Not Listed | Wherever found |
| Eriophyllum nevinii | Nevin's wooly-sunflower | 1 | Not Listed | Wherever found |
| Eriophyllum nubigenum | Yosemite wooly-sunflower | 1 | Not Listed | Wherever found |
| Erithalis fruticosa | No common name | 4 | Not Listed | Wherever found |
| erodium macrophyllum | Large-leaved filaree | 6 | Not Listed | Wherever found |
| Eryngium aristulatum hooveri | Hoover's button-celery | 1 | Not Listed | Wherever found |
| Eryngium pinnatisectum | Tuolumne coyote-thistle | 1 | Not Listed | Wherever found |
| Eryngium racemosum | Delta coyote-thistle | 1 | Not Listed | Wherever found |
| Eryngium spinosepalum | Spinysepaled eryngo | 1 | Not Listed | Wherever found |
| Erysimum ammophilum | Coast wallflower | 1 | Not Listed | Wherever found |
| Erysimum franciscanum | San Francisco wallflower | 1 | Not Listed | Wherever found |
| Erysimum insulare insulare | Island wallflower | 1 | Not Listed | Wherever found |
| Erythrina eggersii | Pinon espinoso or cockspur | 4 | Not Listed | Wherever found |
| Erythroecia hebardi | Hebard's noctuid moth | 3 | Not Listed | Wherever found |
| Erythronium citrinum rodrickii | Lemon colored fawn-lily | 1 | Not Listed | Wherever found |
| Erythronium elegans | No common name | 1 | Not Listed | Wherever found |
| Erythronium tuolumnense | Tuolumne fawn-lily | 1 | Not Listed | Wherever found |
| Eschscholzia multiflora twisselmannii | No common name | 1 | Not Listed | Wherever found |
| Eschscholzia procera | Kernville poppy | 1 | Not Listed | Wherever found |
| Eschscholzia rhombipetala | Diamond-petaled poppy | 1 | Not Listed | Wherever found |
| Escobaria albicolumnaria | White column cory cactus | 2 | Not Listed | Wherever found |
| escobaria alversonii | Foxtail cactus | 6 | Not Listed | Wherever found |
| Escobaria hesteri | Hester's cory cactus | 2 | Not Listed | Wherever found |
| Escobaria villardii | Villard's pincushion cactus | 2 | Not Listed | Wherever found |
| Etheostoma aquali | Coppercheek darter | 4 | Not Listed | Wherever found |
| Etheostoma chuckwachatte | lipstick darter | 4 | Not Listed | Wherever found |
| Etheostoma collis | Carolina Darter | 4 | Not Listed | Wherever found |
| Etheostoma corona | Crown darter | 4 | Not Listed | Wherever found |
| Etheostoma ditrema | Coldwater darter | 4 | Not Listed | Wherever found |
| Etheostoma douglasi | Tuskaloosa darter | 4 | Not Listed | Wherever found |
| Etheostoma grahami | Rio Grande darter | 2 | Not Listed | Wherever found |
| Etheostoma zonistium | bandfin darter | 4 | Not Listed | Wherever found |
| Ethmia monachella | Lost ethmiid moth | 6 | Not Listed | Wherever found |
| Eucephalus gormanii | Gorman aster | 1 | Not Listed | Wherever found |
| Eucephalus vialis | Wayside aster | 1 | Not Listed | Wherever found |
| Eucerceris ruficeps | Redheaded sphecid wasp | 1 | Not Listed | Wherever found |
| Euchemotrema cheatumi | Palmetto pillsnail | 2 | Not Listed | Wherever found |
| Euchemotrema hubrichti | Carinate pillsnail | 3 | Not Listed | Wherever found |
| Euchlaena milnei | [Unnamed] looper moth | 5 | Not Listed | Wherever found |
| Euchloe hyantis andrewsi | Andrew's marble butterfly | 1 | Not Listed | Wherever found |
| Eucosma hennei | Henne's eucosman moth | 1 | Not Listed | Wherever found |
| Euderma maculatum | Spotted bat | 2 | Not Listed | Wherever found |
| Eudyptes chrysolophus | macaroni penguin | Foreign | Not Listed | Campbell Plateau portion of New Zealand/Australia population |
| Eugenia bellonis | No common name | 4 | Not Listed | Wherever found |
| Eugenia margarettae | No common name | 4 | Not Listed | Wherever found |
| Eugenia underwoodii | No common name | 4 | Not Listed | Wherever found |
| Eulimnadia agassizii | Faxon's clam shrimp | 5 | Not Listed | Wherever found |
| Eulimnadia stoningtonensis | Connecticut clam shrimp | 5 | Not Listed | Wherever found |
| Eulonchus marialiciae | Mary Alice's smallheaded fly | 4 | Not Listed | Wherever found |
| Eumaeus atala florida | Florida atala butterfly | 4 | Not Listed | Wherever found |
| Eumeces gilberti arizonensis | Arizona Gilbert's skink | 2 | Not Listed | Wherever found |
| eumeces gilberti ssp. rubricaudatus | Western red-tailed skink | 2 | Not Listed | Wherever found |
| Eumeces skiltonianus interparietalis | Coronado skink | 1 | Not Listed | Wherever found |
| Eumops glaucinus floridanus | Florida mastiff-bat | 4 | Not Listed | Wherever found |
| Eumops perotis californicus | Greater western mastiff-bat | 2 | Not Listed | Wherever found |
| Eumops underwoodi | Underwood's mastiff-bat | 2 | Not Listed | Wherever found |
| Eumorsea pinaleno | Pinaleno monkey grasshopper | 2 | Not Listed | Wherever found |
| Eupatorium leucolepis novae-angliae | White-bracted, New England thoroughwort | 5 | Not Listed | Wherever found |
| Eupatorium resinosum | Pine barrens boneset | 5 | Not Listed | Wherever found |
| Eupelmus nihoaensis | Nihoa eupelmus wasp | 1 | Not Listed | Wherever found |
| Euphilotes enoptes ssp. | Dark blue | 1 | Not Listed | Wherever found |
| Euphilotes rita mattoni | Mattoni's blue | 1 | Not Listed | Wherever found |
| Euphilotes rita ssp. | Sand Mountain blue | 1 | Not Listed | Wherever found |
| Euphorbia macropus | No common name | 2 | Not Listed | Wherever found |
| euphorbia misera | Cliff spurge | 8 | Not Listed | Wherever found |
| Euphorbia purpurea | Darlington's spurge | 5 | Not Listed | Wherever found |
| Euphydryas anicia morandi | Morand's checkerspot | 1 | Not Listed | Wherever found |
| Euphydryas editha monoensis | Mono checkerspot | 1 | Not Listed | Wherever found |
| Eurhychium pringlei | No common name | 4 | Not Listed | Wherever found |
| Eurya sandwicensis | No common name | 1 | Not Listed | Wherever found |
| Eurybia avita | Alexander's rock-aster | 4 | Not Listed | Wherever found |
| Eurybia eryngiifolia | Coyote-thistle aster | 4 | Not Listed | Wherever found |
| Eurybia furcata | [Unnamed] aster | 3 | Not Listed | Wherever found |
| Eurybia mirabilis | Piedmont Aster | 4 | Not Listed | Wherever found |
| Eurybia spinulosa | [Unnamed] aster | 4 | Not Listed | Wherever found |
| Eurycea aquatica | Dark-sided salamander | 4 | Not Listed | Wherever found |
| Eutamias quadrivittatus australis | Organ Mountains Colorado chipmunk | 2 | Not Listed | Wherever found |
| Eutamias umbrinus nevadensis | Hidden Forest Uinta chipmunk | 1 | Not Listed | Wherever found |
| Eximacris phenax | Big Cedar grasshopper | 2 | Not Listed | Wherever found |
| Eximacris superbum | Superb grasshopper | 2 | Not Listed | Wherever found |
| Exocarpos gaudichaudii | No common name | 1 | Not Listed | Wherever found |
| falco columbarius | Merlin | 7 | Not Listed | Wherever found |
| Falco mexicanus | Prairie Falcon | 2 | Not Listed | Wherever found |
| Falco peregrinus | Peregrine Falcon | 8 | Not Listed | Wherever found |
| Falco sparverius paulus | Southeastern American kestrel | 4 | Not Listed | Wherever found |
| Falco sparverius paulus | American Kestrel | 9 | Not Listed | Wherever found |
| Fallicambarus jeanae | [Unnamed] crayfish | 4 | Not Listed | Wherever found |
| Farula davisi | Green Springs Mountain farulan caddisfly | 1 | Not Listed | Wherever found |
| Farula jewetti | Mt. Hood farulan caddisfly | 1 | Not Listed | Wherever found |
| Farula reapiri | Tombstone Prairie farulan caddisfly | 1 | Not Listed | Wherever found |
| Farula sp. | Long-tailed caddisfly | 1 | Not Listed | Wherever found |
| Felis concolor browni | Yuma puma | 2 | Not Listed | Wherever found |
| Felis concolor schorgeri | Wisconsin puma | 3 | Not Listed | Wherever found |
| Ferocactus viridescens | Coast barrel cactus | 1 | Not Listed | Wherever found |
| Ferrissia mcneili | Hood ancylid | 4 | Not Listed | Wherever found |
| Filipendula occidentalis | Queen-of-the-forest | 1 | Not Listed | Wherever found |
| Fimbristylis hawaiiensis | No common name | 1 | Not Listed | Wherever found |
| Fontelicella davisi | Davis County springsnail | 2 | Not Listed | Wherever found |
| Fontelicella metcalfi | Presidio County springsnail | 2 | Not Listed | Wherever found |
| Fontigens holsingeri | Tapered cavesnail | 5 | Not Listed | Wherever found |
| Fontigens turritella | Greenbrier cavesnail | 5 | Not Listed | Wherever found |
| Forchhammeria polyandra | No common name | 4 | Not Listed | Wherever found |
| Forestiera segregata pinetorum | No common name | 4 | Not Listed | Wherever found |
| Franklinia alatamaha | Franklin tree | 4 | Not Listed | Wherever found |
| Frasera coloradensis | No common name | 6 | Not Listed | Wherever found |
| Frasera fastigiata | Umpqua green-gentian | 1 | Not Listed | Wherever found |
| Frasera pahutensis | [Unnamed] green-gentian | 1 | Not Listed | Wherever found |
| Fratercula arctica | Atlantic puffin | 5 | Not Listed | Wherever found |
| Fritillaria eastwoodiae | Butte fritillary | 1 | Not Listed | Wherever found |
| Fritillaria falcata | Talus fritillary | 1 | Not Listed | Wherever found |
| Fritillaria liliacea | Fragrant fritillary | 1 | Not Listed | Wherever found |
| Fritillaria ojaiensis | Ojai frtillary | 1 | Not Listed | Wherever found |
| Fritillaria pluriflora | [Unnamed] adobe-lily | 1 | Not Listed | Wherever found |
| Fritillaria viridea | San Benito fritillary | 1 | Not Listed | Wherever found |
| Fulica caribaea | Caribbean coot | 4 | Not Listed | Puerto Rican |
| Fundulus waccamensis | Waccamaw killifish | 4 | Not Listed | Wherever found |
| Gaillardia aestivalis winkleri | White blanketflower | 2 | Not Listed | Wherever found |
| Galactia eggersii | No common name | 4 | Not Listed | Wherever found |
| Galactia pinetorum | [Unnamed] milkpea | 4 | Not Listed | Wherever found |
| Galium angustifolium borregoense | Borrego bedstraw | 1 | Not Listed | Wherever found |
| galium angustifolium ssp. jacinticum | San Jacinto Mountains bedstraw | 6 | Not Listed | Wherever found |
| Galium californicum luciense | Cone Peak bedstraw | 1 | Not Listed | Wherever found |
| Galium californicum primum | San Jacinto bedstraw | 1 | Not Listed | Wherever found |
| Galium catalinense acrispum | San Clemente island bedstraw | 1 | Not Listed | Wherever found |
| Galium correllii | Cliff bedstraw | 2 | Not Listed | Wherever found |
| Galium grande | San Gabriel bedstraw | 1 | Not Listed | Wherever found |
| Galium hilendiae kingstonense | Kingston bedstraw | 1 | Not Listed | Wherever found |
| Gambelia speciosa | Island snapdragon | 1 | Not Listed | Wherever found |
| gambelia wislizenii | Long-nosed leopard lizard | 2 | Not Listed | Wherever found |
| gambelia wislizenii ssp. wislizenii | Large-spotted leopard lizard | 2 | Not Listed | Wherever found |
| Gambusia senilis | Blotched gambusia | 2 | Not Listed | Wherever found |
| Gammarus bousfieldi | Bousfield's amphipod | 4 | Not Listed | Wherever found |
| Gastrocopta dalliana dalliana | Shortneck snaggletooth | 2 | Not Listed | Wherever found |
| gavia immer | Common loon | 7 | Not Listed | Wherever found |
| Gelochelidon nilotica | Gull-billed Tern | 6 | Not Listed | Wherever found |
| Gentiana latidens | Balsam Mountain Gentian | 4 | Not Listed | |
| Gentiana pennelliana | Wiregrass gentian | 4 | Not Listed | Wherever found |
| Gentiana plurisetosa | Klamath gentian | 1 | Not Listed | Wherever found |
| Gentiana setigera | Mendocino gentian | 1 | Not Listed | Wherever found |
| Gentianella wislizenii | No common name | 2 | Not Listed | Wherever found |
| Geomys bursarius arenarius | Desert pocket gopher | 2 | Not Listed | Wherever found |
| Geomys cumberlandius | Cumberland pocket gopher | 4 | Not Listed | Wherever found |
| Geomys personatus maritimus | Maritime Texas pocket gopher | 2 | Not Listed | Wherever found |
| Geomys personatus streckeri | Carrizo Springs Texas pocket gopher | 2 | Not Listed | Wherever found |
| Geomys texensis bakeri | Baker's Llano pocket gopher | 2 | Not Listed | Wherever found |
| Geothlypis trichas insperata | Brownsville common yellowthroat | 2 | Not Listed | Wherever found |
| Geothlypis trichas sinuosa | Common Yellowthroat | 1 | Not Listed | Wherever found |
| Geum geniculatum | Bent avens | 4 | Not Listed | Wherever found |
| Geum lobatum | Lobed Barren Strawberry | 4 | Not Listed | |
| Gila alvordensis | Alvord chub | 1 | Not Listed | Wherever found |
| Gila bicolor oregonensis | XL Spring tui chub | 1 | Not Listed | Wherever found |
| Gila bicolor ssp. | Summer Basin tui chub | 1 | Not Listed | Summer Basin |
| Gila bicolor ssp. | Catlow tui chub | 1 | Not Listed | Catlow |
| Gila orcuttii | Arroyo chub | 1 | Not Listed | Wherever found |
| Gilia maculata | Little San Bernardino Mountains gilia | 1 | Not Listed | Wherever found |
| Githopsis diffusa filicaulis | Mission Canyon bluecup | 1 | Not Listed | Wherever found |
| Glacicavicola bathysciodes | Blind cave leiodid | 1 | Not Listed | Wherever found |
| Glandularia maritima | No common name | 4 | Not Listed | Wherever found |
| Glandularia tampensis | [Unnamed] vervain | 4 | Not Listed | Wherever found |
| Glaresis arenata | Kelso Dune glaresis scarab | 1 | Not Listed | Wherever found |
| glossopetalon clokeyi | Clokey greasebush | 6 | Not Listed | Wherever found |
| Glossopetalon clokeyi | Clokey's forsellesia | 1 | Not Listed | Wherever found |
| Glossopetalon pungens glabra | Smooth pungent forsellesia | 1 | Not Listed | Wherever found |
| Glyceria nubigena | Smoky Mountains manna grass | 4 | Not Listed | Wherever found |
| Glyphodes cyanomichla | Blue glyphodes moth | 1 | Not Listed | Wherever found |
| Glyphodes exaula | Green glyphodes moth | 1 | Not Listed | Wherever found |
| Glyphopsyche missouri | Missouri glyphopsyche caddisfly | 3 | Not Listed | Wherever found |
| Glyphyalinia clingmani | Fragile supercoil | 4 | Not Listed | Wherever found |
| Glyphyalinia pecki | Blind glyph | 4 | Not Listed | Wherever found |
| Glyphyalinia raderi | Maryland glyph | 5 | Not Listed | Wherever found |
| Gnaphalium obtusifolium saxicola | Saxicola rock catfoot | 3 | Not Listed | Wherever found |
| Goeracea oregona | Sagehen Creek goeracean caddisfly | 1 | Not Listed | Wherever found |
| Gomphus lynnae | Lynn's clubtail | 1 | Not Listed | Wherever found |
| Gomphus parvidens carolinus | Sandhills clubtail | 4 | Not Listed | Wherever found |
| Graffenrieda ottoschulzii | Petites Graines camasey | 4 | Not Listed | Wherever found |
| Grammitis nimbata | Dwarf polypody | 4 | Not Listed | Wherever found |
| Graphis sterlingiana | Sterlings lips | 4 | Not Listed | |
| Graptemys pseudogeographica | False map turtle | 6 | Not Listed | Wherever found |
| Grindelia hirsuta maritima | San Francisco gumplant | 1 | Not Listed | Wherever found |
| Grindelia howellii | Howell's gumplant | 1 | Not Listed | Wherever found |
| Grindelia stricta blakei | Humboldt Bay gumplant | 1 | Not Listed | Wherever found |
| Gronocarus multispinosus | Spiny Florida sandhill scarab | 4 | Not Listed | Wherever found |
| Gryllotalpa major | Prairie mole cricket | 3 | Not Listed | Wherever found |
| Gulo gulo luteus | California wolverine | 1 | Not Listed | Wherever found |
| Gymnocarpium sp. | Sp. nov. ined. (Appalachian) oak fern | 5 | Not Listed | Wherever found |
| Gymnocthebius maureenae | Maureen's gymnocthebius minute moss beetle | 4 | Not Listed | Wherever found |
| Hackelia brevicula | Poison Canyon stickseed | 1 | Not Listed | Wherever found |
| Hackelia cronquistii | Cronquist's stickseed | 1 | Not Listed | Wherever found |
| Haematopus bachmani | Black Oystercatcher | 9 | Not Listed | Wherever found |
| Haematopus palliatus | American Oystercatcher | 4 | Not Listed | Wherever found |
| Haliplus nitens | Disjunct crawling water beetle | 2 | Not Listed | Wherever found |
| Halocaridina palahemo | [Unnamed] shrimp | 1 | Not Listed | Wherever found |
| Haplopappus carthamoides subsquarrosus | No common name | 6 | Not Listed | Wherever found |
| Haplopappus palmeri palmeri | Palmer's haplopappus | 1 | Not Listed | Wherever found |
| Haploperla chukcho | Chukcho stonefly | 4 | Not Listed | Wherever found |
| Harpagonella palmeri | Palmer's grapplinghook | 1 | Not Listed | Wherever found |
| Harpagonella palmeri palmeri | Palmer's grapplinghook | 1 | Not Listed | Wherever found |
| Hastingsia atropurpurea | No common name | 1 | Not Listed | Wherever found |
| Hastingsia bracteosa | No common name | 1 | Not Listed | Wherever found |
| Hazardia cana | Island hazardia | 1 | Not Listed | Wherever found |
| Hedeoma pilosum | Old Blue mock pennyroyal | 2 | Not Listed | Wherever found |
| Hedyotis elatior | No common name | 1 | Not Listed | Wherever found |
| Hedyotis formosa | No common name | 1 | Not Listed | Wherever found |
| Hedyotis littoralis | No common name | 1 | Not Listed | Wherever found |
| Hedyotis nigricans pulvinata | [Unnamed] diamondflowers | 4 | Not Listed | Wherever found |
| Hedyotis tryblium | No common name | 1 | Not Listed | Wherever found |
| Hedysarum occidentale canone | No common name | 6 | Not Listed | Wherever found |
| Helianthella castanea | Diablo rock-rose | 1 | Not Listed | Wherever found |
| Helianthemum dumosum | Bushy rush-rose | 5 | Not Listed | Wherever found |
| Helianthus carnosus | No common name | 4 | Not Listed | Wherever found |
| Helianthus debilis vestitus | Gulf beach sunflower | 4 | Not Listed | Wherever found |
| Helianthus niveus tephrodes | Algodones Dunes sunflower | 1 | Not Listed | Wherever found |
| Helianthus nuttallii parishii | Los Angeles sunflower | 1 | Not Listed | Wherever found |
| Helianthus praecox hirtus | Dimmit sunflower | 2 | Not Listed | Wherever found |
| Helicodiscus diadema | Shaggy coil | 5 | Not Listed | Wherever found |
| Helicodiscus hexodon | Toothy coil | 4 | Not Listed | Wherever found |
| Helicopsyche paralimnella | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Helisoma jacksonense | Jackson Lake snail | 6 | Not Listed | Wherever found |
| Helminthoglypta allynsmithi | Merced Canyon shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta arrosa pomoensis | Pomo bronze shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta arrosa williamsi | Williams' bronze shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta callistoderma | Kern shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta mohaveana | Victorville shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta nickliniana awania | Peninsula Coast Range shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta nickliniana bridgesi | Bridges' Coast Range shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta sequoicola consors | Redwood shoulderband | 1 | Not Listed | Wherever found |
| Helminthoglypta traski coelata | Peninsular Range shoulderband | 1 | Not Listed | Wherever found |
| Heloderma suspectum cinctum | Banded gila monster | 1 | Not Listed | Wherever found |
| Hemipachnolia subporphyria subporphyria | Venus flytrap noctuid | 4 | Not Listed | Wherever found |
| Hemitremia flammea | Flame chub | 4 | Not Listed | Wherever found |
| Hemizonia arida | Red Rock tarweed | 1 | Not Listed | Wherever found |
| Hemizonia floribunda | Tecate tarweed | 1 | Not Listed | Wherever found |
| Hemizonia minthornii | Santa Susana tarweed | 1 | Not Listed | Wherever found |
| Hemizonia mohavensis | Mojave tarweed | 1 | Not Listed | Wherever found |
| Hemizonia multicaulis multicaulis | Seaside tarweed | 1 | Not Listed | Wherever found |
| Hemizonia multicaulis vernalis | Tiburon tarweed | 1 | Not Listed | Wherever found |
| Hemizonia parryi australis | Southern tarplant | 1 | Not Listed | Wherever found |
| Hemizonia parryi congdonii | Pappose spikeweed | 1 | Not Listed | Wherever found |
| Hemizonia pungens laevis | Smooth tarplant | 1 | Not Listed | Wherever found |
| Hepialus sciophanes | [Unnamed] ghost moth | 4 | Not Listed | Wherever found |
| Herricka horrida | No common name | 6 | Not Listed | Wherever found |
| Hesperia comma ssp. | Spring Mountain comma skipper | 1 | Not Listed | Wherever found |
| hesperia comma ssp. mojavensis | Spring Mountains comma skipper butterfly | 2 | Not Listed | Wherever found |
| Hesperia mirimae ssp. | White Mountains skipper | 1 | Not Listed | Wherever found |
| Hesperoleucus parvipinnis | Gualala Roach | 1 | Not Listed | Wherever found |
| Hesperolinon adenophyllum | Glandular dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperolinon bicarpellatum | Two carpeled dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperolinon breweri | Brewer's dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperolinon didymocarpum | Lake County dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperolinon drymarioides | Drymaria dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperolinon tehamense | Tehama dwarf-flax | 1 | Not Listed | Wherever found |
| Hesperopsis gracielae | MacNeill sooty wing skipper | 1 | Not Listed | Wherever found |
| Heteramphus filicum | Oahu heteramphus fern weevil | 1 | Not Listed | Wherever found |
| Heterocleon berneri | Berner's two-winged mayfly | 4 | Not Listed | Wherever found |
| Heterodermia erinacea | No common name | 1 | Not Listed | Wherever found |
| Heterotheca rutteri | No common name | 2 | Not Listed | Wherever found |
| Heuchera hirsutissima | shaggyhair alumroot | 1 | Not Listed | Wherever found |
| Hexalectris nitida | Glass Mountain coral-root | 2 | Not Listed | Wherever found |
| Hexalectris warnockii | Purple, Texas spike | 2 | Not Listed | Wherever found |
| Hexastylis contracta | No common name | 4 | Not Listed | Wherever found |
| Hexastylis rhombiformis | French Broad heartleaf | 4 | Not Listed | Wherever found |
| Hibiscadelphus crucibracteatus | Hau kuahiwi | 1 | Not Listed | Wherever found |
| Hibiscus kokio | Pualoalo | 1 | Not Listed | Wherever found |
| hieracium fendleri | Mogollon hawkweed | 2 | Not Listed | Wherever found |
| Hieracium pringlei | Pringle hawkweed | 2 | Not Listed | Wherever found |
| Hieracium robinsonii | [Unnamed] hawkweed | 5 | Not Listed | Wherever found |
| hoita strobilina | Loma Prieta hoita | 8 | Not Listed | Wherever found |
| Holcobius pikoensis | Piko anobiid beetle | 1 | Not Listed | Wherever found |
| Hollisteria lanata | Hollisteria | 1 | Not Listed | Wherever found |
| Holmgrenanthe petrophila | Rock lady | 1 | Not Listed | Wherever found |
| Holocarpha virgata elongata | No common name | 1 | Not Listed | Wherever found |
| Homoeoneuria cahabensis | Cahaba sandfiltering mayfly | 4 | Not Listed | Wherever found |
| Homoeoneuria dolani | Blackwater sandfiltering mayfly | 4 | Not Listed | Wherever found |
| Homoplectra schuhi | Schuh's homoplectran caddisfly | 1 | Not Listed | Wherever found |
| hordeum intercedens | Vernal barley | 6 | Not Listed | Wherever found |
| Horkelia bolanderi | Bolander's horkelia | 1 | Not Listed | Wherever found |
| Horkelia congesta ssp. congesta | shaggy horkelia | 1 | Not Listed | Wherever found |
| Horkelia cuneata sericea | Wedge-leaved horkelia | 1 | Not Listed | Wherever found |
| Horkelia marinensis | Point Reyes horkelia | 1 | Not Listed | Wherever found |
| Horkelia parryi | Parry's horkelia | 1 | Not Listed | Wherever found |
| Horkelia tularensis | Tulare horkelia | 1 | Not Listed | Wherever found |
| Horkelia wilderae | Barton Flats horkelia | 1 | Not Listed | Wherever found |
| Horologion speokites | Arbuckle Cave ground beetle | 5 | Not Listed | Wherever found |
| Huleechius marroni carolus | Marron's San Carlos riffle beetle | 2 | Not Listed | Wherever found |
| Hulsea vestita ssp. callicarpha | Beautiful Hulsea | 8 | Not Listed | Wherever found |
| Hybognathus argyritis | Western silvery minnow | 6 | Not Listed | Wherever found |
| Hybognathus placitus | Plains minnow | 6 | Not Listed | Wherever found |
| Hydraena maureenae | Maureen's hydraenan minute moss beetle | 5 | Not Listed | Wherever found |
| Hydrochara rickseckeri | Ricksecker's water scavenger beetle | 1 | Not Listed | Wherever found |
| Hydrochus sp. | Seth Forest water scavenger beetle | 5 | Not Listed | Wherever found |
| Hydromantes platycephalus | Mount Lyell salamander | 1 | Not Listed | Wherever found |
| Hydromantes sp. | Owens Valley web-toes salamander | 1 | Not Listed | Wherever found |
| Hydroporus elusivus | Elusive hydroporus diving beetle | 5 | Not Listed | Wherever found |
| Hydroporus folkertsi | Folkerts' hydroporus diving beetle | 4 | Not Listed | Wherever found |
| Hydroporus hirsutus | Wooly hydroporus diving beetle | 1 | Not Listed | Wherever found |
| Hydroporus leechi | Leech's skyline diving beetle | 1 | Not Listed | Wherever found |
| Hydroporus simplex | Simple hydroporus diving beetle | 1 | Not Listed | Wherever found |
| Hydroporus spangleri | Spangler's hydroporus diving beetle | 6 | Not Listed | Wherever found |
| Hydroporus sulphurius | Sulphur Springs hydroporus diving beetle | 4 | Not Listed | Wherever found |
| Hydroporus utahensis | Utah hydroporus diving beetle | 6 | Not Listed | Wherever found |
| Hydropsyche reiseni | Reisen's hydropsyche caddisfly | 2 | Not Listed | Wherever found |
| Hydroptila chelops | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Hydroptila englishi | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Hydroptila lagoi | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Hygrotus curvipes | Curved-foot hygrotus diving beetle | 1 | Not Listed | Wherever found |
| Hygrotus fontinalis | Travertine band-thigh diving beetle | 1 | Not Listed | Wherever found |
| Hygrotus sylvanus | Sylvan hygrotus diving beetle | 3 | Not Listed | Wherever found |
| Hylaeus andrenoides | Andrenoid yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus anomala | Anomalous yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus caeruleipennis | Bluewing yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus chlorosticata | Chlorostictan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus communis | Comes yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus coniceps | Conehead yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus crabronoides | Crabronoid yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus difficilis | Difficult yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus dimidiatus | Dimidiatan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus filicum | Fern yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus flavifrons | Very yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus flavipes | Yellow-foot yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus fuscipennis | Darkwing yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus haleakalae | Haleakala yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus hirsutulus | Hirsute yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus hostilis | Hostile yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus hula | Hulan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus insignis | Insignis yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus kauaiensis | Kauai yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus koae | Koa yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus kona | Kona yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus laeta | Laetan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus obscurata | Obscuratan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus ombrias | Ombrias yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus perkinsianus | Perkin's yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus pubescens | Furry yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus satellus | Satellus yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus simplex | Simple yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus specularis | Specular yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus sphecodoides | Sphecodoid yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus unica | Unique yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus vicina | Vicinan yellow-faced bee | 1 | Not Listed | Wherever found |
| Hylaeus volatilis | Volatile yellow-faced bee | 1 | Not Listed | Wherever found |
| Hymenocallis coronaria | Shoals spider-lily | 4 | Not Listed | Wherever found |
| Hymenocallis godfreyi | Godfrey's spiderlily | 4 | Not Listed | Wherever found |
| Hymenophyllum tayloriae | gorge filmy fern | 4 | Not Listed | Wherever found |
| Hymenophyllum tunbrigense | Tunbridge fern | 4 | Not Listed | Wherever found |
| Hypericum adpressum | No common name | 5 | Not Listed | Wherever found |
| Hypericum radfordiorum | Radford's St. John's Wort | 4 | Not Listed | |
| Hyposmocoma neckerensis | Necker petrochroan leaf miner | 1 | Not Listed | Wherever found |
| Hypotrachyna virginica | Flaky square britches | 4 | Not Listed | |
| Hysterocarpus traskii pomo | Russian River tule perch | 1 | Not Listed | Wherever found |
| Icaricia icariodes ssp. | Point Reyes blue | 1 | Not Listed | Wherever found |
| Icaricia icarioides moroensis | Morro Bay blue butterfly | 1 | Not Listed | Wherever found |
| icteria virens | Yellow-breasted chat | 6 | Not Listed | Wherever found |
| Icterus cucullatus cucullatus | Mexican hooded oriole | 2 | Not Listed | Wherever found |
| Icterus cucullatus sennetti | Sennett's hooded oriole | 2 | Not Listed | Wherever found |
| Icterus graduacauda audubonii | Audubon's oriole | 2 | Not Listed | Wherever found |
| Icterus gularis | Altamira Oriole | 9 | Not Listed | Wherever found |
| Idia gopheri | Tortoise commensal noctuid moth | 4 | Not Listed | Wherever found |
| Idionycteris phyllotis | Allen's big-eared bat | 6 | Not Listed | Wherever found |
| Idiostatus kathleenae | Pinnacles shield-back katydid | 1 | Not Listed | Wherever found |
| Idiostatus middlekaufi | Middlekauf's shieldback katydid | 1 | Not Listed | Wherever found |
| Iliamna remota | Kankakee globe-mallow | 3 | Not Listed | Wherever found |
| Incisalia mossii ssp. | San Gabriel Mountains elfin | 1 | Not Listed | San Gabriel |
| Incisalia mossii ssp. | Marin elfin | 1 | Not Listed | Marin |
| ionactis caelestis | Red Rock Canyon aster | 6 | Not Listed | Wherever found |
| Ionactis elegans | No common name | 2 | Not Listed | Wherever found |
| Ipomoea krugii | Krug's white morning-glory | 4 | Not Listed | Wherever found |
| Ipomopsis aggregata webberi | No common name | 6 | Not Listed | Wherever found |
| Ipomopsis spicata robruthii | No common name | 6 | Not Listed | Wherever found |
| Iris missouriensis | [Unnamed] iris | 6 | Not Listed | Wherever found |
| Islandiana speophila | Cavern sheet-web spider | 5 | Not Listed | Wherever found |
| Isocoma arguta | Goldenbush | 1 | Not Listed | Wherever found |
| Isoetes lithophila | Rock quillwort | 2 | Not Listed | Wherever found |
| Isoetes virginica | Virginia quillwort | 5 | Not Listed | Wherever found |
| Ithamar annectans | Annectans rhopalid bug | 1 | Not Listed | Wherever found |
| Ithamar hawaiiense | Hawaiian rhopalid bug | 1 | Not Listed | Wherever found |
| Itodacnus novicornis | Necker itodacnus click beetle | 1 | Not Listed | Wherever found |
| Itodacnus paradoxus | Strange itodacnus click beetle | 1 | Not Listed | Wherever found |
| Iva hayesiana | San Diego marsh elder | 1 | Not Listed | Wherever found |
| Ivesia aperta aperta | Sierra Valley ivesia | 1 | Not Listed | Wherever found |
| Ivesia aperta canina | Dog Valley ivesia | 1 | Not Listed | Wherever found |
| Ivesia argyrocoma | Silver-haired ivesia | 1 | Not Listed | Wherever found |
| Ivesia callida | Tahquitz ivesia | 1 | Not Listed | Wherever found |
| Ivesia cryptocaulis | No common name | 1 | Not Listed | Wherever found |
| Ivesia jaegeri | No common name | 1 | Not Listed | Wherever found |
| Ivesia longibracteata | No common name | 1 | Not Listed | Wherever found |
| Ivesia paniculata | Ash Creek ivesia | 1 | Not Listed | Wherever found |
| Ivesia patellifera | Kingston Mountains cinquefoil | 1 | Not Listed | Wherever found |
| Ivesia pickeringii | Pickering ivesia | 1 | Not Listed | Wherever found |
| Ivesia pityocharis | Pine Nut Mountains ivesia | 1 | Not Listed | Wherever found |
| Ivesia rhypara shellyi | Venator Canyon, Shelly's ivesia | 1 | Not Listed | Wherever found |
| Ivesia sericoleuca | Plumas ivesia | 1 | Not Listed | Wherever found |
| Ivesia shockleyi ostleri | No common name | 6 | Not Listed | Wherever found |
| Ixobrychus exilis | Least bittern | 1 | Not Listed | Wherever found |
| Ixoreus naevius | Varied Thrush | 6 | Not Listed | Wherever found |
| Jacquemontia curtissii | Pineland jacquemontia | 4 | Not Listed | Wherever found |
| Jamesia americana zionis | No common name | 6 | Not Listed | Wherever found |
| Jamesianthus alabamensis | Alabama jamesianthus | 4 | Not Listed | Wherever found |
| Jamesia tetrapetala | No common name | 6 | Not Listed | Wherever found |
| Jepsonia malvifolia | Island jepsonia | 1 | Not Listed | Wherever found |
| Juglans californica hindsii | Northern California black walnut | 1 | Not Listed | Wherever found |
| Juglans californica var. californica | California walnut | 1 | Not Listed | Wherever found |
| Juglans cinerea | Butternut | 4 | Not Listed | Wherever found |
| Juncus caesariensis | New Jersey rush | 5 | Not Listed | Wherever found |
| Juncus leiospermus var. ahartii | Ahart's dwarf rush | 1 | Not Listed | Wherever found |
| Justicia borinquensis | No common name | 4 | Not Listed | Wherever found |
| Justicia crassifolia | Thick-leaved water-willow | 4 | Not Listed | Wherever found |
| Justicia culebritae | No common name | 4 | Not Listed | Wherever found |
| Justicia runyonii | Runyon's water-willow | 2 | Not Listed | Wherever found |
| Justicia wrightii | Wright's water-willow | 2 | Not Listed | Wherever found |
| Kalania hawaiiensis | Lanai kalanian leaf bug | 1 | Not Listed | Wherever found |
| Kalania sp. | Oahu kalanian leaf bug | 1 | Not Listed | Wherever found |
| Kalmia cuneata | White-wicky | 4 | Not Listed | Wherever found |
| Kauaiina ioxantha | Ioxanthan looper | 1 | Not Listed | Wherever found |
| Kenkia glandulosa | [Unnamed] planarian | 3 | Not Listed | Wherever found |
| Kenkia rhynchida | [Unnamed] planarian | 1 | Not Listed | Wherever found |
| Kinosternon flavescens flavescens | Yellow mud turtle | 3 | Not Listed | Wherever found |
| Kinosternon hirtipes murrayi | Big Bend mud turtle | 2 | Not Listed | Wherever found |
| Kleptochthonius henroti | Greenbrier Valley cave pseudoscorpion | 5 | Not Listed | Wherever found |
| Kleptochthonius hetricki | Organ Cave pseudoscorpion | 5 | Not Listed | Wherever found |
| Kleptochthonius orpheus | Orpheus cave pseudoscorpion | 5 | Not Listed | Wherever found |
| Kleptochthonius proserpinae | Proserpina cave pseudoscorpion | 5 | Not Listed | Wherever found |
| Koanophyllon droserolepis | Oreganillo | 4 | Not Listed | Wherever found |
| Lachnocaulon digynum | Tiny bog buttons | 4 | Not Listed | Wherever found |
| Lagopus muta evermanni | Evermann's rock ptarmigan | 7 | Not Listed | Wherever found |
| Lagopus muta yunaskensis | Yunaska rock ptarmigan | 7 | Not Listed | Wherever found |
| Lambdina canitiaria | [Unnamed] looper moth | 5 | Not Listed | Wherever found |
| Laminella sanguinea | [Unnamed] snail | 1 | Not Listed | Wherever found |
| lampetra tridentata | Pacific lamprey | 1 | Not Listed | Wherever found |
| Lampetra tridentata | Goose Lake lamprey | 1 | Not Listed | Goose Lake |
| lampropeltis getula ssp. californiae | California king snake | 8 | Not Listed | Wherever found |
| Lampropeltis zonata parvirubra | San Bernardino mountain king snake | 1 | Not Listed | Wherever found |
| Lampropeltis zonata pulchra | San Diego Mountain king snake | 1 | Not Listed | Wherever found |
| Lampsilis binominata | Lined pocketbook | 4 | Not Listed | Wherever found |
| Lampsilis cariosa | Yellow lampmussel | 5 | Not Listed | Wherever found |
| Lampsilis haddletoni | Haddleton lampmussel | 4 | Not Listed | Wherever found |
| Lanius ludovicianus | Loggerhead Shrike | 1 | Not Listed | Wherever found |
| Lanius ludovicianus migrans | Migrant loggerhead shrike | 3 | Not Listed | Wherever found |
| Lantana depressa | No common name | 4 | Not Listed | Wherever found |
| Larca laceyi | Lacey's cave pseudoscorpion | 1 | Not Listed | Wherever found |
| larus atricilla | Laughing gull | 1 | Not Listed | Wherever found |
| lasionycteris noctivagans | Silver-haired bat | 7 | Not Listed | Wherever found |
| Lasiurus ega | Southern Yellow Bat | 8 | Not Listed | Wherever found |
| Lasmigona sp. | Barrens heelsplitter | 4 | Not Listed | Wherever found |
| Lasthenia glabrata coulteri | Seaside, Coulter's daisy | 1 | Not Listed | Wherever found |
| Lasthenia macrantha prisca | Slender meadowfoam | 1 | Not Listed | Wherever found |
| Laterallus jamaicensis | Black Rail | 4 | Not Listed | Wherever found |
| laterallus jamaicensis ssp. coturniculus | California black rail | 8 | Not Listed | Wherever found |
| Lathyrus jepsonii jepsonii | Delta tule-pea | 1 | Not Listed | Wherever found |
| Lathyrus torreyi | Torrey's pea | 1 | Not Listed | Wherever found |
| Lavatera assurgentiflora | Island tree mallow | 1 | Not Listed | Wherever found |
| Lavinia symmetricus mitrulus | Pit roach | 1 | Not Listed | Wherever found |
| Lavinia symmetricus ssp. | Red Hills roach | 1 | Not Listed | Wherever found |
| Layia discoidea | Rayless layia | 1 | Not Listed | Wherever found |
| Layia heterotricha | Pale-yellow layia | 1 | Not Listed | Wherever found |
| Layia jonesii | Jones layia | 1 | Not Listed | Wherever found |
| Layia leucopappa | Comanche layia | 1 | Not Listed | Wherever found |
| Layia platyglossa | Ziegler's layia | 1 | Not Listed | Wherever found |
| Leavenworthia crassa elongata | [Unnamed] glade cress | 4 | Not Listed | Wherever found |
| Leavenworthia exigua lutea | [Unnamed] glade cress | 4 | Not Listed | Wherever found |
| Lecanora masana | No common name | 4 | Not Listed | |
| Lecanora xanthosora | No common name | 1 | Not Listed | Wherever found |
| Lechea divaricata | No common name | 4 | Not Listed | Wherever found |
| Lechea lakelae | No common name | 4 | Not Listed | Wherever found |
| Legenere limosa | Legenere | 1 | Not Listed | Wherever found |
| Leitneria floridana | Corkwood | 4 | Not Listed | Wherever found |
| Lejeunea blomquistii | No common name | 4 | Not Listed | Wherever found |
| Lentipes concolor | O`opu alamo`o | 1 | Not Listed | Wherever found |
| Lepanthopsis melanantha | Tiny orchid | 4 | Not Listed | Wherever found |
| Lepechinia cardiophylla | Heart-leaved pitcher-sage | 1 | Not Listed | Wherever found |
| Lepechinia ganderi | Gander's pitcher-sage | 1 | Not Listed | Wherever found |
| Lepidium bidentatum remyi | Remy's `anaunau | 1 | Not Listed | Wherever found |
| Lepidium davisii | Davis' pepper cress | 1 | Not Listed | Wherever found |
| Lepidium flavum felipense | Borrego Valley peppergrass | 1 | Not Listed | Wherever found |
| Lepidium jaredii album | Panoche peppergrass | 1 | Not Listed | Wherever found |
| Lepidium jaredii jaredii | Jared's peppergrass | 1 | Not Listed | Wherever found |
| Lepidium serra | `Anaunau | 1 | Not Listed | Wherever found |
| lepidium virginicum var. robinsonii | Robinson's pepper-grass | 2 | Not Listed | Wherever found |
| Lepidospartum burgessii | Gypsum scalebroom | 2 | Not Listed | Wherever found |
| Lepidostoma astaneum | Goeden's lepidostoman caddisfly | 1 | Not Listed | Wherever found |
| Lepidostoma ermanae | Cold Spring caddisfly | 1 | Not Listed | Wherever found |
| Lepidostoma etnieri | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Lepraria lanata | Appalachian dust bunnies | 4 | Not Listed | |
| Leptachatina lepida | [Unnamed] snail | 1 | Not Listed | Wherever found |
| Leptodactylon glabrum | No common name | 1 | Not Listed | Wherever found |
| Leptodactylon pungens hazeliae | No common name | 1 | Not Listed | Wherever found |
| Leptodactylon sp. | Sp. nov. ined. leptodactylon | 6 | Not Listed | Wherever found |
| Leptogryllus deceptor | Oahu deceptor bush cricket | 1 | Not Listed | Wherever found |
| Leptothymenium sharpii | Mt. Leconte moss | 4 | Not Listed | Wherever found |
| Leptoxis crassa | Boulder snail | 4 | Not Listed | Wherever found |
| Leptoxis melanoides | Black mudalia | 4 | Not Listed | Wherever found |
| Leptoxis minor | Knob mudalia | 4 | Not Listed | Wherever found |
| Leptoxis praerosa | Onyx rocksnail | 4 | Not Listed | Wherever found |
| Lepus americanus tahoensis | Sierra Nevada snowshoe hare | 1 | Not Listed | Wherever found |
| Lepus californicus bennettii | San Diego black-tailed jackrabbit | 1 | Not Listed | Wherever found |
| Lesquerella carinata | Keeled bladderpod | 6 | Not Listed | Wherever found |
| Lesquerella garrettii | Garrett bladder-pod | 6 | Not Listed | Wherever found |
| Lesquerella humilis | [Unnamed] bladderpod | 6 | Not Listed | Wherever found |
| Lesquerella macrocarpa | Large-fruited bladder-pod | 6 | Not Listed | Wherever found |
| Lesquerella paysonii | [Unnamed] bladderpod | 6 | Not Listed | Wherever found |
| Lesquerella pruinosa | [Unnamed] bladder-pod | 6 | Not Listed | Wherever found |
| Lessingia arachnoidea | No common name | 1 | Not Listed | Wherever found |
| Lessingia glandulifera tomentosa | Warner Springs lessingia | 1 | Not Listed | Wherever found |
| Lessingia micradenia micradenia | No common name | 1 | Not Listed | Wherever found |
| Lessingia micradenia var. glabrata | smooth lessingia | 1 | Not Listed | Wherever found |
| Leucosticte atrata | Black Rosy-Finch | 6 | Not Listed | Wherever found |
| Lewisia cotyledon heckneri | Heckner's lewisia | 1 | Not Listed | Wherever found |
| Lewisia cotyledon howellii | Howell's lewisia | 1 | Not Listed | Wherever found |
| Lewisia cotyledon purdyi | No common name | 1 | Not Listed | Wherever found |
| Lewisia longipetala | Long-petaled lewisia | 1 | Not Listed | Wherever found |
| Lewisia maguirei | No common name | 1 | Not Listed | Wherever found |
| Lewisia serrata | Saw-toothed lewisia | 1 | Not Listed | Wherever found |
| Lewisia stebbinsii | Stebbins lewisia | 1 | Not Listed | Wherever found |
| Liatris borealis | [Unnamed] blazingstar | 5 | Not Listed | Wherever found |
| Liatris provincialis | Godfrey's blazingstar | 4 | Not Listed | Wherever found |
| Liatris tenuis | Slender gay-feather | 2 | Not Listed | Wherever found |
| Lichnanthe albopilosa | White sand bear scarab | 1 | Not Listed | Wherever found |
| Lichnanthe ursina | Bumblebee scarab | 1 | Not Listed | Wherever found |
| Lilaeopsis masonii | Mason's lilaeopsis | 1 | Not Listed | Wherever found |
| Lilium grayi | Gray's lily | 5 | Not Listed | Wherever found |
| Lilium humboldtii ocellatum | Humboldt lily | 1 | Not Listed | Wherever found |
| Lilium maritimum | Coast lily | 1 | Not Listed | Wherever found |
| Lilium parryi | Lemon lily | 1 | Not Listed | Wherever found |
| Limbella fryei | No common name | 1 | Not Listed | Wherever found |
| Limenitus archippus lahontani | Nevada viceroy | 1 | Not Listed | Wherever found |
| Limenitus weidemeyerii nevadae | Nevada admiral | 1 | Not Listed | Wherever found |
| Limnadia lenticularis | American clam shrimp | 5 | Not Listed | Wherever found |
| Limnanthes bakeri | Baker's meadowfoam | 1 | Not Listed | Wherever found |
| Limnanthes douglasii sulphurea | Point Reyes meadowfoam | 1 | Not Listed | Wherever found |
| Limnanthes floccosa bellingeriana | Bellinger's meadowfoam | 1 | Not Listed | Wherever found |
| Limnanthes floccosa ssp. pumila | Dwarf meadowfoam | 1 | Not Listed | Wherever found |
| Limnanthes gracilis ssp. gracilis | slender meadowfoam | 1 | Not Listed | Wherever found |
| Limnebius aridus | Animas minute moss beetle | 2 | Not Listed | Wherever found |
| Limnebius texanus | Texas minute moss beetle | 2 | Not Listed | Wherever found |
| Limnebius utahensis | Utah minute moss beetle | 6 | Not Listed | Wherever found |
| Limnephilus atercus | Fort Dick limnephilus caddisfly | 1 | Not Listed | Wherever found |
| Limnodromus griseus | Short-billed Dowitcher | 6 | Not Listed | Wherever found |
| Limosa fedoa | Marbled Godwit | 6 | Not Listed | Wherever found |
| Limosella pubiflora | Chiricahua mudwort | 2 | Not Listed | Wherever found |
| Limotettix sp. | Barrens sedge leafhopper | 5 | Not Listed | Wherever found |
| Linanthus concinnus | [Unnamed] linanthus | 1 | Not Listed | Wherever found |
| Linanthus harknessii condensatus | Plaskett Meadows linanthus | 1 | Not Listed | Wherever found |
| Linanthus killipii | Baldwin Lake linanthus | 1 | Not Listed | Wherever found |
| Linanthus nuttallii howellii | Mt. Tedoc linanthus | 1 | Not Listed | Wherever found |
| Linanthus orcuttii | Orcutt's linanthus | 1 | Not Listed | Wherever found |
| Linderiella santarosae | Santa Rosa linderiella | 1 | Not Listed | Wherever found |
| Linum carteri smallii | [Unnamed] flax | 4 | Not Listed | Wherever found |
| Linum macrocarpum | [Unnamed] flax | 4 | Not Listed | Wherever found |
| Linum sulcatum harperi | No common name | 4 | Not Listed | Wherever found |
| Lipochaeta degeneri | Small-leaved nehe | 1 | Not Listed | Wherever found |
| Lipochaeta tenuis | Nehe | 1 | Not Listed | Wherever found |
| Lithasia armigera | Armored rocksnail | 4 | Not Listed | Wherever found |
| Lithasia geniculata | Ornate rocksnail | 4 | Not Listed | Wherever found |
| Lithasia jayana | Rugose rocksnail | 4 | Not Listed | Wherever found |
| Lithasia lima | Warty rocksnail | 4 | Not Listed | Wherever found |
| Lithasia salebrosa | Muddy rocksnail | 4 | Not Listed | Wherever found |
| Lithasia verrucosa | Varicose rocksnail | 4 | Not Listed | Wherever found |
| Litsea aestivalis | Pondspice | 4 | Not Listed | Wherever found |
| Lobelia dunbariae | No common name | 1 | Not Listed | Wherever found |
| lobelia yuccoides | panaunau | 1 | Not Listed | Wherever found |
| Lomatium concinnum | Adobe desert-parsley | 6 | Not Listed | Wherever found |
| Lomatium congdonii | Congdon's lomatium | 1 | Not Listed | Wherever found |
| Lomatium erythrocarpum | Red-fruited desert-parsley | 1 | Not Listed | Wherever found |
| Lomatium graveolens clarkii | [Unnamed] desert-parsley | 6 | Not Listed | Wherever found |
| Lomatium greenmanii | Greenman's desert-parsley | 1 | Not Listed | Wherever found |
| Lomatium insulare | San Nicolas Island lomatium | 1 | Not Listed | Wherever found |
| Lomatium shevockii | Owens Peak lomatium | 1 | Not Listed | Wherever found |
| Lomatium stebbinsii | Stebbins' lomatium | 1 | Not Listed | Wherever found |
| Lomatium suksdorfii | Suksdorf's desert-parsley | 1 | Not Listed | Wherever found |
| Lomatium tuberosum | Hoover's desert-parsley | 1 | Not Listed | Wherever found |
| Lophocolea appalachiana | No common name | 4 | Not Listed | Wherever found |
| Lorandersonia microcephala | Small-headed goldenweed | 2 | Not Listed | Wherever found |
| Lordithon niger | Black lordithon rove beetle | 5 | Not Listed | Wherever found |
| Lotus argophyllus niveus | Silver, Santa Cruz Island hosackia | 1 | Not Listed | Wherever found |
| Lotus crassifolius otayensis | Otay lotus | 1 | Not Listed | Wherever found |
| Lotus nuttallianus | Prostrate hosackia | 1 | Not Listed | Wherever found |
| Lotus purshianus helleri | No common name | 4 | Not Listed | Wherever found |
| Lotus rubriflorus | Red-flowered lotus | 1 | Not Listed | Wherever found |
| Lotus unifoliolatus var. helleri | Heller's bird's-foot trefoil | 4 | Not Listed | Wherever found |
| Loxia curvirostra | Red crossbill | 4 | Not Listed | Wherever found |
| Luina serpentina | No common name | 1 | Not Listed | Wherever found |
| Lunania ekmanii | No common name | 4 | Not Listed | Wherever found |
| Luperina trigona | [Unnamed] noctuid moth | 4 | Not Listed | Wherever found |
| Lupinus antoninus | Anthony Peak lupine | 1 | Not Listed | Wherever found |
| Lupinus arboreus eximius | Lupine, San Mateo tre | 1 | Not Listed | Wherever found |
| Lupinus citrinus | Orange lupine | 1 | Not Listed | Wherever found |
| Lupinus crassus | No common name | 6 | Not Listed | Wherever found |
| Lupinus cusickii | Cusick's lupine | 1 | Not Listed | Wherever found |
| Lupinus duranii | Mono Lake lupine | 1 | Not Listed | Wherever found |
| Lupinus excubitus medius | Mountains Springs bush lupine | 1 | Not Listed | Wherever found |
| Lupinus guadalupensis | Guadalupe Island lupine | 1 | Not Listed | Wherever found |
| Lupinus ludovicianus | San Luis lupine | 1 | Not Listed | Wherever found |
| Lupinus luteolus | Pale yellow lupine | 1 | Not Listed | Wherever found |
| Lupinus magnificus magnificus | Panamint Mountains lupine | 1 | Not Listed | Wherever found |
| Lupinus oreganus var. oreganus | Biddle's lupine | 1 | Not Listed | Wherever found |
| Lupinus padre-crowleyi | DeDecker's lupine | 1 | Not Listed | Wherever found |
| Lupinus spectabilis | Shaggy-hair lupine | 1 | Not Listed | Wherever found |
| Lupinus westianus | Gulfcoast lupine | 4 | Not Listed | Wherever found |
| Lutra canadensis sonora | Southwestern otter | 2 | Not Listed | Wherever found |
| Lycaena dorcas claytoni | Clayton's copper | 5 | Not Listed | Wherever found |
| Lycaena rubicus ssp. | White Mountains copper | 1 | Not Listed | Wherever found |
| Lycium hassei | Santa Catalina Island desert-thorn | 1 | Not Listed | Wherever found |
| Lycium texanum | Texas wolfberry | 2 | Not Listed | Wherever found |
| lycopodium phlegmaria var. | disciplina | 6 | Not Listed | Wherever found |
| Lyonothamnus floribundus asplenifolius | Fern-leaved ironwood | 1 | Not Listed | Wherever found |
| Lyonothamnus floribundus floribundus | Catalina ironwood | 1 | Not Listed | Wherever found |
| Lysimachia fraseri | Fraser's yellow loosestrife | 4 | Not Listed | Wherever found |
| Lysimachia kalalauensis | No common name | 1 | Not Listed | Wherever found |
| Lysimachia sp. | Sp. nov. ined. lysimachia | 1 | Not Listed | Wherever found |
| Lythrurus snelsoni | Ouachita Mountain shiner | 2 | Not Listed | Wherever found |
| Lytrosis permagnaria | [Unnamed] looper moth | 4 | Not Listed | Wherever found |
| Lytta hoppingi | Hopping's blister beetle | 1 | Not Listed | Wherever found |
| Lytta inseparata | Mojave Desert blister beetle | 1 | Not Listed | Wherever found |
| Lytta mirifica | Anthony blister beetle | 2 | Not Listed | Wherever found |
| Lytta moesta | Moestan blister beetle | 1 | Not Listed | Wherever found |
| Lytta molesta | Molestan blister beetle | 1 | Not Listed | Wherever found |
| Lytta morrisoni | Morrison's blister beetle | 1 | Not Listed | Wherever found |
| Machaeranthera asteroides lagunensis | Laguna Mountains aster | 1 | Not Listed | Wherever found |
| Machiloides perkinsi | Perkin's club-palp bristletail | 1 | Not Listed | Wherever found |
| Macrobaenetes kelsoensis | Kelso giant sand treader cricket | 1 | Not Listed | Wherever found |
| Macrobaenetes valgum | Coachella giant sand treader cricket | 1 | Not Listed | Wherever found |
| Macromia taeniolata | Wabash belted skimmer | 3 | Not Listed | Wherever found |
| Macrotus californicus | California leaf-nosed bat | 2 | Not Listed | Wherever found |
| Madia hallii | Hall's madia | 1 | Not Listed | Wherever found |
| madia radiata | Showy madia | 6 | Not Listed | Wherever found |
| Madia stebbinsii | Stebbins' madia | 1 | Not Listed | Wherever found |
| Magnolia ashei | Ashe's magnolia | 4 | Not Listed | Wherever found |
| Malaclemys terrapin littoralis | Texas diamondback terrapin | 2 | Not Listed | Wherever found |
| Malaclemys terrapin pileata | Mississippi diamondback terrapin | 4 | Not Listed | Wherever found |
| Malaclemys terrapin terrapin | Northern diamondback terrapin | 5 | Not Listed | Wherever found |
| Malacothamnus abbottii | Abbott's bush-mallow | 1 | Not Listed | Wherever found |
| malacothamnus arcuatus | Arcuate bush mallow | 6 | Not Listed | Wherever found |
| Malacothamnus davidsonii | Davidson's bush-mallow | 1 | Not Listed | Wherever found |
| Malacothamnus mendocinensis | Mendocino bush-mallow | 1 | Not Listed | Wherever found |
| Malacothamnus palmeri involucratus | Carmel Valley bush-mallow | 1 | Not Listed | Wherever found |
| Malacothamnus palmeri lucianus | Arroyo Seco bush-mallow | 1 | Not Listed | Wherever found |
| Malacothamnus parishii | Parish's bush-mallow | 1 | Not Listed | Wherever found |
| Malacothrix crispifolia | No common name | 1 | Not Listed | Wherever found |
| Malacothrix intermedia | No common name | 1 | Not Listed | Wherever found |
| Malacothrix saxatilis arachnoidea | Carmel Valley malacothrix | 1 | Not Listed | Wherever found |
| Malaxis bayardii | Appalachian Adder's-mouth | 4 | Not Listed | |
| Malaxis brachypoda | Adder's-mouth | 1 | Not Listed | Wherever found |
| Malpighia infestissima | Stingingbush | 4 | Not Listed | Wherever found |
| Manfreda longiflora | Runyon huaco | 2 | Not Listed | Wherever found |
| Mappia racemosa | No common name | 4 | Not Listed | Wherever found |
| Marina orcuttii orcuttii | California marina | 1 | Not Listed | Wherever found |
| Marsdenia elliptica | No common name | 4 | Not Listed | Wherever found |
| Marshallia ramosa | No common name | 4 | Not Listed | Wherever found |
| Masticophis flagellum ruddocki | San Joaquin whipsnake | 1 | Not Listed | Wherever found |
| masticophis flagellum ssp. piceus | Red coachwhip | 6 | Not Listed | Wherever found |
| Matelea alabamensis | [Unnamed] anglepod | 4 | Not Listed | Wherever found |
| Matelea baldwyniana | [Unnamed] anglepod | 4 | Not Listed | Wherever found |
| Matelea floridana | No common name | 4 | Not Listed | Wherever found |
| Matelea radiata | Falfurrias anglepod | 2 | Not Listed | Wherever found |
| Maytenus elongata | Cuero de sapo | 4 | Not Listed | Wherever found |
| Meconella oregana | White fairypoppy | 1 | Not Listed | Wherever found |
| Megalagrion adytum | Adytum megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megalagrion amaurodytum peles | Pele megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megalagrion amaurodytum waianaeanum | Waianae megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megalagrion molokaiense | Molokai megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megalagrion nigrohamatum nigrohamatum | Nigrohamatum megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megalagrion oahuense | Oahu megalagrion damselfly | 1 | Not Listed | Wherever found |
| Megaleuctra sierra | Shirttail Creek stonefly | 1 | Not Listed | Wherever found |
| Megascolides macelfreshi | Oregon giant earthworm | 1 | Not Listed | Wherever found |
| megomphix hemphilli | Oregon megomphix | 1 | Not Listed | Wherever found |
| Melanerpes lewis | Lewis's Woodpecker | 6 | Not Listed | Wherever found |
| Melanerpes uropygialis | Gila Woodpecker | 6 | Not Listed | Wherever found |
| Melanthera parvifolia | No common name | 4 | Not Listed | Wherever found |
| Melicope cruciata | Alani | 1 | Not Listed | Wherever found |
| Melicope haleakalae | Alani | 1 | Not Listed | Wherever found |
| Melicope nealae | Alani | 1 | Not Listed | Wherever found |
| Melicope wailauensis | Alani | 1 | Not Listed | Wherever found |
| Melospiza lincolnii | Lincoln's Sparrow | 1 | Not Listed | Wherever found |
| Melospiza melodia maxillaris | Song Sparrow | 1 | Not Listed | Wherever found |
| Melospiza melodia pusillula | Song Sparrow | 1 | Not Listed | Wherever found |
| Melospiza melodia samuelis | Song Sparrow | 1 | Not Listed | Wherever found |
| Mentzelia argillosa | Clay blazing-star | 6 | Not Listed | Wherever found |
| Mentzelia multicaulis var. librina | No common name | 6 | Not Listed | Wherever found |
| Merolonche dolli | Doll's merolonche | 5 | Not Listed | Wherever found |
| Mertensia drummondii | Drummond bluebell | 7 | Not Listed | Wherever found |
| Merycomyia brunnea | Brown merycomyian tabanid fly | 4 | Not Listed | Wherever found |
| Mesadenus polyanthus | [Unnamed] ladies'-tresses | 4 | Not Listed | Wherever found |
| Mesodon clausus trossulus | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Mesodon clingmanicus | Clingman covert | 4 | Not Listed | Wherever found |
| Metapogon hurdi | Hurd's metapogon robberfly | 1 | Not Listed | Wherever found |
| Metrarga obscura | Mauna Loa metrargan seed bug | 1 | Not Listed | Wherever found |
| Metrichia volada | Page Spring micro caddisfly | 2 | Not Listed | Wherever found |
| Metromenus bardus | Heavy metromenus ground beetle | 1 | Not Listed | Wherever found |
| Metromenus cuneipennis | Wedge-winged metromenus ground beetle | 1 | Not Listed | Wherever found |
| Metromenus oceanicus | Oceanic metromenus ground beetle | 1 | Not Listed | Wherever found |
| Micranthemum micranthemoides | Nuttall's micranthemum | 5 | Not Listed | Wherever found |
| Micranthes hitchcockiana | Saddle Mountain saxifrage | 1 | Not Listed | Wherever found |
| Micrarionta facta | Santa Barbara islandsnail | 1 | Not Listed | Wherever found |
| Micrarionta feralis | San Nicolas islandsnail | 1 | Not Listed | Wherever found |
| Micrarionta gabbii | San Clemente islandsnail | 1 | Not Listed | Wherever found |
| Micrarionta opuntia | Pricklypear islandsnail | 1 | Not Listed | Wherever found |
| Micrarionta rowelli bakerensis | [Unnamed] islandsnail | 1 | Not Listed | Wherever found |
| Micrarionta rowelli mccoiana | California McCoy snail islandsnail | 1 | Not Listed | Wherever found |
| Micrathene whitneyi | Elf owl | 6 | Not Listed | Wherever found |
| Microcina homi | Hom's micro-blind harvestman | 1 | Not Listed | Wherever found |
| Microcina leei | Lee's micro-blind harvestman | 1 | Not Listed | Wherever found |
| Microcina lumi | Lum's micro-blind harvestman | 1 | Not Listed | Wherever found |
| Microcina tiburona | Tiburon micro-blind harvestman | 1 | Not Listed | Wherever found |
| Microcreagris imperialis | Empire Cave pseudoscorpion | 1 | Not Listed | Wherever found |
| Microcylleopus fomicoideus | [Unnamed] riffle beetle | 1 | Not Listed | Wherever found |
| Microcylleopus similis | [Unnamed] riffle beetle | 1 | Not Listed | Wherever found |
| Microdipodops megacephalus albiventer | Desert Valley kangaroo mouse | 1 | Not Listed | Wherever found |
| Microdipodops megacephalus nasutus | Fletcher dark kangaroo mouse | 1 | Not Listed | Wherever found |
| Micromus cookeorum | Cookes' brown lacewing | 1 | Not Listed | Wherever found |
| Micromus haleakalae | Haleakala micromus brown lacewing | 1 | Not Listed | Wherever found |
| Micromus lobipennis | Lobe-wing brown lacewing | 1 | Not Listed | Wherever found |
| Micromus swezeyi | Swezey's brown lacewing | 1 | Not Listed | Wherever found |
| Micronaspis floridana | Florida intertidal firefly | 4 | Not Listed | Wherever found |
| Micropterus treculii | Guadalupe bass | 2 | Not Listed | Wherever found |
| microseris douglasii ssp. platycarpha | Small-flowered microseris | 6 | Not Listed | Wherever found |
| Microseris howellii | No common name | 1 | Not Listed | Wherever found |
| Microseris laciniata detlingii | No common name | 1 | Not Listed | Wherever found |
| Microtus breweri | Beach vole | 5 | Not Listed | Wherever found |
| Microtus californicus mohavensis | Mojave river vole | 1 | Not Listed | Wherever found |
| Microtus californicus stephensi | Stephens' California vole | 1 | Not Listed | Wherever found |
| Microtus californicus vallicola | Owens Valley California vole | 1 | Not Listed | Wherever found |
| Microtus chrotorrhinus carolinensis | Southern rock vole | 5 | Not Listed | Wherever found |
| Microtus mexicanus navaho | Navaho Mountain Mexican vole | 2 | Not Listed | Wherever found |
| Microtus montanus fucosus | Pahranagat Valley montane vole | 1 | Not Listed | Wherever found |
| Microtus montanus nevadensis | Ash Meadows montane vole | 1 | Not Listed | Wherever found |
| Microtus montanus rivularis | Virgin River montane vole | 6 | Not Listed | Wherever found |
| Microtus oeconomus amakensis | Amak tundra vole | 7 | Not Listed | Wherever found |
| Microtus oeconomus elymocetes | Montague tundra vole | 7 | Not Listed | Wherever found |
| Microtus pennsylvanicus kincaidi | Potholes meadow vole | 1 | Not Listed | Wherever found |
| Microtus pennsylvanicus provectus | Block Island meadow vole | 5 | Not Listed | Wherever found |
| Microtus pennsylvanicus shattucki | Penobscot meadow vole | 5 | Not Listed | Wherever found |
| miktoniscus | (Miktoniscus) isopod | 6 | Not Listed | Wherever found |
| Miloderes nelsoni | Nelson's miloderes weevil | 1 | Not Listed | Wherever found |
| Miloderes rulieni | Rulien's miloderes weevil | 1 | Not Listed | Wherever found |
| Mimosa quadrivalvis var. urbaniana | Zarzarilla | 4 | Not Listed | Wherever found |
| Mimulus brandegeei | Santa Cruz Island monkey-flower | 1 | Not Listed | Wherever found |
| mimulus diffusus | Palomar monkeyflower | 6 | Not Listed | Wherever found |
| Mimulus exiguus | San Bernardino Mountains monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus filicaulis | Hetch Hetchy monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus hymenophyllus | No common name | 1 | Not Listed | Wherever found |
| Mimulus jungermannioides | No common name | 1 | Not Listed | Wherever found |
| Mimulus mohavensis | Mojave monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus patulus | Stalk-leaved monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus purpureus purpureus | Purple monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus pygmaeus | Egg Lake monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus ringens colpophilus | Square-stemmed monkey-flower | 5 | Not Listed | Wherever found |
| Mimulus traskiae | Santa Catalina monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus washingtonensis washingtonensis | Washington monkey-flower | 1 | Not Listed | Wherever found |
| Mimulus whipplei | Whipple's monkey-flower | 1 | Not Listed | Wherever found |
| Minuartia decumbens | The Lassics sandwort | 1 | Not Listed | Wherever found |
| Minuartia marcescens | No common name | 5 | Not Listed | Wherever found |
| Mirabilis nyctaginea | Sandhill four-o'clock | 2 | Not Listed | Wherever found |
| Mirabilis rotundifolia | Roundleaf four-o'clock | 6 | Not Listed | Wherever found |
| Mitoura gryneus sweadneri | Sweadner's olive hairstreak | 4 | Not Listed | Wherever found |
| Mixogaster delongi | Delong's mixogaster flower fly | 4 | Not Listed | Wherever found |
| Moho bishopi | Bishop's `o`o | 1 | Not Listed | Wherever found |
| Monadenia circumcarinata | Keeled sideband | 1 | Not Listed | Wherever found |
| Monadenia hillebrandi yosemitensis | Yosemite mariposa sideband | 1 | Not Listed | Wherever found |
| Monadenia mormonum buttoni | Button's Sierra sideband | 1 | Not Listed | Wherever found |
| Monadenia mormonum hirsuta | Hirsute sierra sideband | 1 | Not Listed | Wherever found |
| Monarda fistulosa brevis | [Unnamed] horse-mint | 5 | Not Listed | Wherever found |
| Monardella crispa | Crisp monardella | 1 | Not Listed | Wherever found |
| Monardella douglasii venosa | Veiny monardella | 1 | Not Listed | Wherever found |
| Monardella frutescens | San Luis Obispo monardella | 1 | Not Listed | Wherever found |
| Monardella leucocephala | Merced monardella | 1 | Not Listed | Wherever found |
| Monardella linoides oblonga | Flax-like monardella | 1 | Not Listed | Wherever found |
| Monardella nana leptosiphon | San Felipe monardella | 1 | Not Listed | Wherever found |
| Monardella pringlei | Pringle monardella | 1 | Not Listed | Wherever found |
| Monardella robisonii | Robison's monardella | 1 | Not Listed | Wherever found |
| monardella villosa ssp. globosa | Robust monardella | 6 | Not Listed | Wherever found |
| Monotropa uniflora | Indian pipe | 4 | Not Listed | Wherever found |
| Monotropsis odorata | Pygmypipes | 4 | Not Listed | Wherever found |
| Monotropsis odorata | Sweet pinesap | 4 | Not Listed | Wherever found |
| Montia howellii | Howell's montia | 1 | Not Listed | Wherever found |
| moxostoma congestum | Gray redhorse | 2 | Not Listed | Wherever found |
| Moxostoma valenciennesi | Greater redhorse | 6 | Not Listed | Wherever found |
| Muhlenbergia californica | California muhly | 1 | Not Listed | Wherever found |
| Muilla clevelandii | San Diego goldenstar | 1 | Not Listed | Wherever found |
| Mustela frenata peninsulae | Florida long-tailed weasel | 4 | Not Listed | Wherever found |
| Mycoporum biseptatum | Charred volcanoes | 4 | Not Listed | |
| Mycotrupes pedester | Scrub Island burrowing scarab | 4 | Not Listed | Wherever found |
| myiarchus tyrannulus | Brown-crested flycatcher | 6 | Not Listed | Wherever found |
| Myosurus minimus | tiny mousetail | 1 | Not Listed | Wherever found |
| Myosurus minimus apus | Little mousetail | 1 | Not Listed | Wherever found |
| Myotis austroriparius | Southeastern myotis | 4 | Not Listed | Wherever found |
| myotis californicus | California myotis | 8 | Not Listed | Wherever found |
| Myotis evotis | Long-eared myotis | 6 | Not Listed | Wherever found |
| myotis keenii | Keen's myotis | 7 | Not Listed | Wherever found |
| Myotis lucifugus occultus | Occult little brown bat | 2 | Not Listed | Wherever found |
| Myotis thysanodes | Fringed myotis | 6 | Not Listed | Wherever found |
| Myotis thysanodes pahasapensis | Fringed-tailed myotis | 6 | Not Listed | Wherever found |
| Myotis velifer | Cave myotis | 2 | Not Listed | Wherever found |
| Myotis volans | Long-legged myotis | 6 | Not Listed | Wherever found |
| Myotis yumanensis | Yuma myotis | 1 | Not Listed | Wherever found |
| Myrcianthes fragrans simpsonii | Simpson stopper | 4 | Not Listed | Wherever found |
| Myriophyllum laxum | No common name | 4 | Not Listed | Wherever found |
| Myrmosula pacifica | Antioch mutillid wasp | 1 | Not Listed | Wherever found |
| Najas flexilis | Fish Lake naiad | 6 | Not Listed | Wherever found |
| nama stenocarpum | Nama nama | 6 | Not Listed | Wherever found |
| Navarretia heterandra | Tehama pincushionplant | 6 | Not Listed | Wherever found |
| Navarretia myersii ssp. deminuta | Myers' pincushionplant | 8 | Not Listed | Wherever found |
| navarretia nigelliformis ssp. nigelliformis | Adobe navarretia | 6 | Not Listed | Wherever found |
| Navarretia prostrata | prostrate pincushionplant | 1 | Not Listed | Wherever found |
| Nebria darlingtoni | South Forks ground beetle | 1 | Not Listed | Wherever found |
| Nebria gebleri siskiyouensis | Siskiyou ground beetle | 1 | Not Listed | Wherever found |
| nebria gebleri ssp. cascadensis | (Nebria gebleri cascadensis) ground beetle | 6 | Not Listed | Wherever found |
| nebria kincaidi ssp. balli | (Nebria kincaidi balli) ground beetle | 6 | Not Listed | Wherever found |
| nebria paradisi | (Nebria paradisi) ground beetle | 6 | Not Listed | Wherever found |
| Nebria sahlbergii triad | Trinity Alps ground beetle | 1 | Not Listed | Wherever found |
| Necydalis rudei | Rude's long-horned beetle | 1 | Not Listed | Wherever found |
| Neduba longipennis | Santa Monica shieldback katydid | 1 | Not Listed | Wherever found |
| Nemacladus twisselmannii | Twisselmann's nemacladus | 1 | Not Listed | Wherever found |
| Nemastylis floridana | Fall-flowering ixia | 4 | Not Listed | Wherever found |
| Nemopalpus nearcticus | Sugarfoot moth fly | 4 | Not Listed | Wherever found |
| Neofiber alleni | Round-tailed muskrat | 4 | Not Listed | Wherever found |
| Neomachiloides heteropus | Hawaiian long-palp bristletail | 1 | Not Listed | Wherever found |
| Neoplanorbis carinatus | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Neoplanorbis smithi | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Neoplanorbis tantillus | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Neoplanorbis umbilicatus | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Neothremma andersoni | Columbia Gorge neothremman caddisfly | 1 | Not Listed | Wherever found |
| Neothremma genella | Golden-horned caddisfly | 1 | Not Listed | Wherever found |
| Neothremma siskiyou | Siskiyou caddisfly | 1 | Not Listed | Wherever found |
| Neotoma floridana haematoreia | Southern Appalachian eastern woodrat | 4 | Not Listed | Wherever found |
| Neotoma fuscipes annectens | San Francisco dusky-footed woodrat | 1 | Not Listed | Wherever found |
| Neotoma fuscipes luciana | Monterey dusky-footed woodrat | 1 | Not Listed | Wherever found |
| Neotoma lepida intermedia | San Diego desert woodrat | 1 | Not Listed | Wherever found |
| Neotoma mexicana bullata | Santa Catalina Mountains woodrat | 2 | Not Listed | Wherever found |
| Neotoma micropus leucophaea | White Sands woodrat | 2 | Not Listed | Wherever found |
| Neotrichia kitae | Kite's neotrichian micro caddisfly | 3 | Not Listed | Wherever found |
| Neritilia hawaiiensis | Anchialine Pool Snail | 1 | Not Listed | Wherever found |
| Nerodia clarkii | Gulf salt marsh snake | 4 | Not Listed | Wherever found |
| Neseis alternata | Kauai band-legged seed bug | 1 | Not Listed | Wherever found |
| Neseis haleakalae | Mt. Haleakala seed bug | 1 | Not Listed | Wherever found |
| Nesidiolestes ana | Ana wingless thread bug | 1 | Not Listed | Wherever found |
| Nesidiolestes insularis | Mt. Tantalus wingless thread bug | 1 | Not Listed | Wherever found |
| Nesidiolestes roberti | Robert's wingless thread bug | 1 | Not Listed | Wherever found |
| Nesidiolestes selium | Selium wingless thread bug | 1 | Not Listed | Wherever found |
| Nesocryptias villosa | Villosan flightless seed bug | 1 | Not Listed | Wherever found |
| Nesomimesa kauaiensis | Kauai nesomimesan sphecid wasp | 1 | Not Listed | Wherever found |
| Nesomimesa perkinsi | Perkins' nesomimesan sphecid wasp | 1 | Not Listed | Wherever found |
| Nesomimesa sciopteryx | Shade-winged nesomimesan sphecid wasp | 1 | Not Listed | Wherever found |
| Nesorestias filicicola | Mt. Tantalus short-wing fern planthopper | 1 | Not Listed | Wherever found |
| Nesosydne acuta | Iao Valley nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne bridwelli | Bridewell's nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne cyrtandrae | Nahiku nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne cyrtandricola | Glenwood nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne kuschei | Kusche's nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne leahi | Diamond Head nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne longipes | Long-footed nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesosydne sulcata | Keanae nesosydne planthopper | 1 | Not Listed | Wherever found |
| Nesotocus giffordi | Gifford's nesotocus weevil | 1 | Not Listed | Wherever found |
| Nesotocus kauaiensis | Kauai nesotocus weevil | 1 | Not Listed | Wherever found |
| Nesotocus munroi | Munro's nesotocus weevil | 1 | Not Listed | Wherever found |
| Nesticus cooperi | Lost Nantahala Cave spider | 4 | Not Listed | Wherever found |
| Nesticus dilutus | Grassy Creek Cave spider | 4 | Not Listed | Wherever found |
| Nesticus furtivus | Crystal Caverns cave spider | 4 | Not Listed | Wherever found |
| Nesticus jonesi | Cave Spring Cave spider | 4 | Not Listed | Wherever found |
| Nesticus valentinei | Valentine's cave spider | 4 | Not Listed | Wherever found |
| Neurocordulia clara | Apalachicola twilight skimmer | 4 | Not Listed | Wherever found |
| Neviusia alabamensis | No common name | 4 | Not Listed | Wherever found |
| Newcombia canaliculata | Newcomb's tree snail | 1 | Not Listed | Wherever found |
| Newcombia perkinsi | Newcomb's tree snail | 1 | Not Listed | Wherever found |
| Newcombia pfeifferi | Newcomb's tree snail | 1 | Not Listed | Wherever found |
| Newcombia sulcata | Newcomb's tree snail | 1 | Not Listed | Wherever found |
| Nolina arenicola | Sand sacahuista | 2 | Not Listed | Wherever found |
| Nolina atopocarpa | [Unnamed] beargrass | 4 | Not Listed | Wherever found |
| Nolina cismontana | Peninsular beargrass | 1 | Not Listed | Wherever found |
| Nolina sp. | Sp. nov. ined. (chaparral) beargrass | 1 | Not Listed | Wherever found |
| Nothochrysa californica | San Francisco lacewing | 1 | Not Listed | Wherever found |
| Notholaena lemmonii | Lemmon fern cloak | 2 | Not Listed | Wherever found |
| Notropis chihuahua | Chihuahua shiner | 2 | Not Listed | Wherever found |
| Notropis hypsilepis | Highscale shiner | 4 | Not Listed | Wherever found |
| Notropis melanostomus | Blackmouth shiner | 4 | Not Listed | Wherever found |
| Noturus insignis ssp. | Spotted madtom | 5 | Not Listed | Wherever found |
| Nucombia plicata | Newcomb's tree snail | 1 | Not Listed | Wherever found |
| Numenius phaeopus | Whimbrel | 6 | Not Listed | Wherever found |
| Numenius tahitiensis | Bristle-thighed curlew | 7 | Not Listed | Wherever found |
| Nuphar luteum ulvaceum | No common name | 4 | Not Listed | Wherever found |
| Nycticorax nycticorax | Black-crowned Night-Heron | 6 | Not Listed | Wherever found |
| nyctinomops femorosaccus | Pocketed free-tailed bat | 6 | Not Listed | Wherever found |
| Nyctinomops macrotis | Big free-tailed bat | 2 | Not Listed | Wherever found |
| Nysius frigatensis | French Frigate Shoal seed bug | 1 | Not Listed | Wherever found |
| Nysius fullawayi | Fullaway's seed bug | 1 | Not Listed | Wherever found |
| Nysius neckerensis | Necker goosefoot seed bug | 1 | Not Listed | Wherever found |
| Nysius nihoae | Nihoa nysius seed bug | 1 | Not Listed | Wherever found |
| Nysius suffusus | Necker bunchgrass seed bug | 1 | Not Listed | Wherever found |
| Oceanides bryani | Bryan's oceanides seed bug | 1 | Not Listed | Wherever found |
| Oceanides perkinsi | Perkins' oceanides seed bug | 1 | Not Listed | Wherever found |
| Oceanides rugosiceps | Rough-headed oceanides seed bug | 1 | Not Listed | Wherever found |
| Ochotona princeps barnesi | Barnes' pika | 6 | Not Listed | Wherever found |
| Ochotona princeps cinnamomea | Cinnamon pika | 6 | Not Listed | Wherever found |
| Ochotona princeps lasalensis | La Sal pika | 6 | Not Listed | Wherever found |
| Ochotona princeps moorei | Heliotrope pika | 6 | Not Listed | Wherever found |
| Ochotona princeps nigrescens | Goat Peak pika | 2 | Not Listed | Wherever found |
| Ochotona princeps wasatchensis | Wasatch pika | 6 | Not Listed | Wherever found |
| Ochotrichia elongiralla | [Unnamed] caddisfly | 4 | Not Listed | Wherever found |
| Ochrotrichia contorta | Contorted ochrotrichian micro caddisfly | 4 | Not Listed | Wherever found |
| Ochrotrichia phenosa | Deschutes ochrotrichian micro caddisfly | 1 | Not Listed | Wherever found |
| Ochrotrichia provosti | Provost's ochrotrichian micro caddisfly | 4 | Not Listed | Wherever found |
| Ochrotrichia vertreesi | Vertrees's ochrotrichian micro caddisfly | 1 | Not Listed | Wherever found |
| Ochthebius crassalus | Wing-shoulder minute moss beetle | 1 | Not Listed | Wherever found |
| Ochthebius putnamensis | Putnam minute moss beetle | 3 | Not Listed | Wherever found |
| Ochthebius reticulus | Wilbur Springs minute moss beetle | 1 | Not Listed | Wherever found |
| Odocoileus virginianus hiltonensis | Hilton Head white-tailed deer | 4 | Not Listed | Wherever found |
| Odocoileus virginianus nigribarbis | Blackbeard Island white-tailed deer | 4 | Not Listed | Wherever found |
| Odocoileus virginianus taurinsulae | Bulls Island white-tailed deer | 4 | Not Listed | Wherever found |
| Odocoileus virginianus venatoria | Hunting Island white-tailed deer | 4 | Not Listed | Wherever found |
| Odynerus nigripennis | Black-winged odynerus vespid wasp | 1 | Not Listed | Wherever found |
| Odynerus niihauensis | Niihau odynerus vespid wasp | 1 | Not Listed | Wherever found |
| Odynerus radula | Radulan odynerus vespid wasp | 1 | Not Listed | Wherever found |
| Odynerus soror | Soror odynerus vespid wasp | 1 | Not Listed | Wherever found |
| Oecanthus laricis | Laricis tree cricket | 3 | Not Listed | Wherever found |
| Oechalia grisea | Gray oechalia stink bug | 1 | Not Listed | Wherever found |
| Oechalia patruelis | Patruelis oechalia stink bug | 1 | Not Listed | Wherever found |
| Oenothera kleinii | Klein's evening-primrose | 6 | Not Listed | Wherever found |
| Oenothera organensis | Organ Mountain evening-primrose | 2 | Not Listed | Wherever found |
| Oenothera pilosella sessilis | [Unnamed] evening-primrose | 4 | Not Listed | Wherever found |
| Oenothera psammophila | [Unnamed] evening-primrose | 1 | Not Listed | Wherever found |
| Oenothera wolfii | Wolf's evening-primrose | 1 | Not Listed | Wherever found |
| Oeobia dryadopa | `Ohenaupaka oeobian moth | 1 | Not Listed | Wherever found |
| Oliarces clara | Cheese-weed moth lacewing | 1 | Not Listed | Wherever found |
| Oliarus consimilis | Kauai parti-colored oliarus planthopper | 1 | Not Listed | Wherever found |
| Oliarus discrepans | Oliarus wild cotton planthopper | 1 | Not Listed | Wherever found |
| Oliarus lihue | Lihue oliarus planthopper | 1 | Not Listed | Wherever found |
| Oliarus myoporicola | Barber's Point oliarus planthopper | 1 | Not Listed | Wherever found |
| Oliarus priola | Priolan oliarus planthopper | 1 | Not Listed | Wherever found |
| Oligophlebodes mostbento | Tombstone Prairie oligophlebodes caddisfly | 1 | Not Listed | Wherever found |
| Omoides anastrepta | Molokai sedge omoides moth | 1 | Not Listed | Wherever found |
| Omoides anastreptoides | Kohala Mountain sedge omoides moth | 1 | Not Listed | Wherever found |
| Omoides asaphombra | `Ohe omoides moth | 1 | Not Listed | Wherever found |
| Omoides euryprora | Ola`a banana omoides moth | 1 | Not Listed | Wherever found |
| Omoides fullawayi | Fullaway's banana omoides moth | 1 | Not Listed | Wherever found |
| Omoides giffardi | Giffard's `ohe omoides moth | 1 | Not Listed | Wherever found |
| Omoides iridias | Kilauea pa`iniu omoides moth | 1 | Not Listed | Wherever found |
| Omoides meyricki | Meyrick's banana omoides moth | 1 | Not Listed | Wherever found |
| Omoides monogona | Hawaiian bean leafroller | 1 | Not Listed | Wherever found |
| Omoides musicola | Maui banana omoides moth | 1 | Not Listed | Wherever found |
| Omoides pritchardii | Hawaiian lo`ulu omoides moth | 1 | Not Listed | Wherever found |
| omus dejeanii | (Omus dejeanii) ground beetle | 6 | Not Listed | Wherever found |
| Oncorhynchus mykiss gibbsi | Interior redband trout | 1 | Not Listed | Wherever found |
| Oncorhynchus mykiss gilberti | Kern River rainbow trout | 1 | Not Listed | Wherever found |
| Oncorhynchus mykiss ssp. | Catlow Valley redband trout | 1 | Not Listed | Catlow Valley |
| Oncorhynchus mykiss ssp. | Warner Valley redband trout | 1 | Not Listed | Wherever found |
| Oncorhynchus mykiss ssp. | Goose Lake redband trout | 1 | Not Listed | Goose Lake |
| oncorhynchus mykiss ssp. irideus | Coastal rainbow trout | 7 | Not Listed | Wherever found |
| Ondatra zibethicus ripensis | Pecos River muskrat | 2 | Not Listed | Wherever found |
| Onthophagus polyphemi | Onthophagus tortoise commensal scarab | 4 | Not Listed | Wherever found |
| Onychobaris langei | Lange's El Segundo Dune weevil | 1 | Not Listed | Wherever found |
| Onychomys torridus ramona | Southern grasshopper mouse | 1 | Not Listed | Wherever found |
| Onychomys torridus tularensis | Tulare grasshopper mouse | 1 | Not Listed | Wherever found |
| Oodemas breviscapum | Nihoa oodemas weevil | 1 | Not Listed | Wherever found |
| Oodemas erro | Wandering oodemas weevil | 1 | Not Listed | Wherever found |
| Oodemas laysanensis | Laysan oodemas weevil | 1 | Not Listed | Wherever found |
| Oodemas neckeri | Necker oodemas weevil | 1 | Not Listed | Wherever found |
| Oonopsis engelmannii | Engelmann's goldenrod | 6 | Not Listed | Wherever found |
| Operculina turpethum var. turpethum | St. Thomas lidpod | 4 | Not Listed | Wherever found |
| Ophiogomphus anomalus | Extra-striped snaketail | 3 | Not Listed | Wherever found |
| Ophiogomphus howei | Midget snaketail | 4 | Not Listed | Wherever found |
| Ophiogomphus sp. | St. Croix snaketail | 3 | Not Listed | Wherever found |
| Ophiogomphus westfalli | Ozark snaketail | 4 | Not Listed | Wherever found |
| Ophisaurus compressus | Island glass lizard | 4 | Not Listed | Wherever found |
| Ophisaurus mimicus | Mimic glass lizard | 4 | Not Listed | Wherever found |
| oporornis tolmiei | Macgillivray's warbler | 7 | Not Listed | Wherever found |
| Optioservus browni | Brown's optioservus riffle beetle | 4 | Not Listed | Wherever found |
| Optioservus canus | Pinnacles optioservus riffle beetle | 1 | Not Listed | Wherever found |
| Opuntia arenaria | Sand prickly-pear | 2 | Not Listed | Wherever found |
| Opuntia basilaris brachyclada | Short-jointed beavertail cactus | 1 | Not Listed | Wherever found |
| Opuntia engelmannii flexospina | Marble-seeded, few-spined prickly-pear | 2 | Not Listed | Wherever found |
| Opuntia heacockul | No common name | 6 | Not Listed | Wherever found |
| Opuntia imbricata argentea | Silver cholla | 2 | Not Listed | Wherever found |
| Opuntia munzii | Munz cholla | 1 | Not Listed | Wherever found |
| Opuntia parryi serpentina | Snake cholla | 1 | Not Listed | Wherever found |
| Opuntia spinosissima | No common name | 4 | Not Listed | Wherever found |
| Opuntia viridiflora | Santa Fe cholla | 2 | Not Listed | Wherever found |
| Oravelia pege | Dry Creek cliff strider bug | 1 | Not Listed | Wherever found |
| Orbexilum macrophyllum | Bigleaf scurf-pea | 4 | Not Listed | Wherever found |
| Orbittacus obscurus | Gold rush hanging fly | 1 | Not Listed | Wherever found |
| orconectes australis ssp. australis | Southern cave crayfish | 4 | Not Listed | Wherever found |
| Orconectes indianensis | Indiana crayfish | 3 | Not Listed | Wherever found |
| Orconectes jeffersoni | Louisville crayfish | 4 | Not Listed | Wherever found |
| Orconectes williamsi | [Unnamed] crayfish | 4 | Not Listed | Wherever found |
| Oregonichthys kalawatseti | Umpqua Oregon Chub | 1 | Not Listed | Wherever found |
| Oreohelix eurekensis eurekensis | Eureka mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix florida | Florida mountainsnail | 2 | Not Listed | Wherever found |
| Oreohelix haydeni corugata | [Unnamed] mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix haydeni haydeni | Lyrate mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix idahoensis idahoensis | Idaho banded mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix jugalis | Boulder pile mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix nevadensis | Schell Creek mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix parowanensis | [Unnamed] mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix strigosa berryi | Berry's mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix strigosa goniogyra | Carinated rocky mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix strigosa ssp. | Pahasapa mountainsnail | 6 | Not Listed | Wherever found |
| Oreohelix vortex | Whorled mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix waltoni | Lava rock mountainsnail | 1 | Not Listed | Wherever found |
| Oreohelix yavapai | Yavapai mountainsnail | 6 | Not Listed | Wherever found |
| Oreoscoptes montanus | Sage Thrasher | 6 | Not Listed | Wherever found |
| Orobanche parishii brachyloba | Short-lobed broomrape | 1 | Not Listed | Wherever found |
| Orobanche valida valida | Rock Creek broomrape | 1 | Not Listed | Wherever found |
| Orthotrichum keeverae | Keever's bristle-moss | 4 | Not Listed | Wherever found |
| Oryctes nevadensis | Nevada oryctes | 1 | Not Listed | Wherever found |
| Oryzomys couesi aquaticus | Coues' rice rat | 2 | Not Listed | Wherever found |
| Osmerus mordax | Rainbow smelt | 5 | Not Listed | Wherever found |
| Osmorhiza mexicana bipatriata | Livermore sweet-cicely | 2 | Not Listed | Wherever found |
| Ostroumovia horii | [Unnamed] hydroid | 1 | Not Listed | Wherever found |
| Ostrya chisosensis | Big Bend hop hornbeam | 2 | Not Listed | Wherever found |
| Otus nudipes newtoni | Virgin Islands screech owl | 4 | Not Listed | Wherever found |
| Ovis canadensis | Bighorn sheep | 8 | Not Listed | Wherever found |
| Oxyethira florida | Florida oxyethiran micro caddisfly | 4 | Not Listed | Wherever found |
| Oxypolis ternata | No common name | 4 | Not Listed | Wherever found |
| Oxytheca caryophylloides | chickweed oxytheca | 1 | Not Listed | Wherever found |
| Oxytheca parishii ciengensis | Cienega Seca oxytheca | 1 | Not Listed | Wherever found |
| Oxytropis campestris wanapum | No common name | 1 | Not Listed | Wherever found |
| Oxytropis sordida barnebyana | No common name | 7 | Not Listed | Wherever found |
| Oxyura jamaicensis jamaicensis | Ruddy Duck | 4 | Not Listed | Puerto Rico |
| Packera bernardina | San Bernardino butterweed | 1 | Not Listed | Wherever found |
| Packera ganderi | Gander butterweed | 1 | Not Listed | Wherever found |
| Packera hartiana | Hart's ragwort | 2 | Not Listed | Wherever found |
| Packera hesperia | No common name | 1 | Not Listed | Wherever found |
| Packera millefolia | Piedmont ragwort | 4 | Not Listed | Wherever found |
| Packera spellenbergii | Spellenberg's groundsel | 2 | Not Listed | Wherever found |
| Paduniella nearctica | Nearctic paduniellan caddisfly | 4 | Not Listed | Wherever found |
| Palaemonetes antrorum | Texas cave shrimp | 2 | Not Listed | Wherever found |
| Palafoxia arida gigantea | Giant spanishneedle | 1 | Not Listed | Wherever found |
| Paleoxenus dohrni | Dohrn's elegant eucnemid beetle | 1 | Not Listed | Wherever found |
| Pandion haliaetus | osprey | 6 | Not Listed | Wherever found |
| Panicum abscissum | Cutthroat grass | 4 | Not Listed | Wherever found |
| Panicum stevensianum | No common name | 4 | Not Listed | Wherever found |
| Panoquina errans | Wandering skipper | 1 | Not Listed | Wherever found |
| Papaipema aerata | [Unnamed] noctuid moth | 5 | Not Listed | Wherever found |
| Papaipema aweme | [Unnamed] noctuid moth | 3 | Not Listed | Wherever found |
| Papaipema sp. | Flypoison borer moth | 5 | Not Listed | Wherever found |
| Papaipema sulphurata | Decodon borer moth | 5 | Not Listed | Wherever found |
| Papaver pygmaeum | No common name | 6 | Not Listed | Wherever found |
| parabuteo unicinctus | Harris's Hawk | 6 | Not Listed | Wherever found |
| Paracoenia calida | Wilbur Springs shore fly | 1 | Not Listed | Wherever found |
| Parapsyche extensa | King's Creek parapsyche caddisfly | 1 | Not Listed | Wherever found |
| Pararhinichthys bowersi | Cheat minnow | 5 | Not Listed | Wherever found |
| Parastrellus hesperus | Canyon bat | 6 | Not Listed | Wherever found |
| Paravitrea aulacogyra | [Unnamed] snail | 4 | Not Listed | Wherever found |
| Paravitrea ceres | Sidelong supercoil | 5 | Not Listed | Wherever found |
| Paravitrea ternaria | Sculpted supercoil | 4 | Not Listed | Wherever found |
| Paravitrea varidens | Roan supercoil | 4 | Not Listed | Wherever found |
| Parnassia caroliniana | Carolina grass-of-parnassus | 4 | Not Listed | Wherever found |
| Parnassia grandifolia | Largeleaf grass of Parnassus | 4 | Not Listed | Wherever found |
| Paronychia ahartii | Ahart's whitlow-wort | 1 | Not Listed | Wherever found |
| Paronychia virginica var. virginica | Silvery nailwort | 5 | Not Listed | Wherever found |
| Paronychia wilkinsonii | Wilkinson's whitlow-wort | 2 | Not Listed | Wherever found |
| Parthenium integrifolium | Wavyleaf wild-quinine | 4 | Not Listed | Wherever found |
| Parthenium tetraneuris | Arkansas River feverfew | 6 | Not Listed | Wherever found |
| Partula salifana | Alifan Tree snail | 1 | Not Listed | Wherever found |
| Partulina anceyana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina carnicolor | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina confusa | Hawai`i tree snail | 1 | Not Listed | Wherever found |
| Partulina crassa | Lanai tree snail | 1 | Not Listed | Wherever found |
| Partulina crocea | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina dolei | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina dubia | Waianae tree snail | 1 | Not Listed | Wherever found |
| Partulina dwightii | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina fusoidea | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina germana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina gouldii | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina grisea | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina horneri | Hawai`i tree snail | 1 | Not Listed | Wherever found |
| Partulina induta | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina kaaeana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina lemmoni | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina marmorata | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina mighelsiana | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina mucida | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina mutabilis | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina natti | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina nivea | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina perdix | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina physa | Hawai`i tree snail | 1 | Not Listed | Wherever found |
| Partulina plumbea | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina porcellana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina proxima | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina radiata | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina redfieldii | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina rufa | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina splendida | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina subpolita | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina tapaniana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina terebra | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina tessellata | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina thaanumiana | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina theodorei | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina ustulata | Maui tree snail | 1 | Not Listed | Wherever found |
| Partulina virgulata | Moloka`i tree snail | 1 | Not Listed | Wherever found |
| Partulina winniei | Maui tree snail | 1 | Not Listed | Wherever found |
| Parula pitiayumi nigrilora | Tropical parula | 2 | Not Listed | Wherever found |
| Passerculus sandwichensis beldingi | Belding's savannah sparrow | 1 | Not Listed | Wherever found |
| Passerculus sandwichensis rostratus | Large-billed savannah sparrow | 1 | Not Listed | Wherever found |