| Scientific Name | English Common Name |
| Aaptos simplex | Sponge |
| Abagrotis brunneipennis | Yankee Dart |
| Abagrotis cupida | Brown Climbing Cutworm |
| Abagrotis dickeli | Moth |
| Abagrotis dodi | Moth |
| Abagrotis duanca | Moth |
| Abagrotis forbesi | Moth |
| Abagrotis glenni | Moth |
| Abagrotis hermina | Moth |
| Abagrotis mirabilis | Moth |
| Abagrotis nanalis | Moth |
| Abagrotis nefascia | Moth |
| Abagrotis orbis | Moth |
| Abagrotis reedi | Moth |
| Abagrotis trigona | Luteous Dart |
| Abagrotis turbulenta | Moth |
| Abagrotis vittifrons | Moth |
| Abdera firma | False Darkling Beetle |
| Aberenicola claparedi oceanica | Rough-Skinned Lugworm |
| Aberenicola claparedi vagabunda | Vagabond Lugworm |
| Abraeus bolteri | Clown Beetle |
| Abraliopsis felis | Squid |
| Abrostola urentis | Moth |
| Abstrusomyzus phloxae | Aphid |
| Acallis gripalis | Moth |
| Acalypta cooleyi | Lace Bug |
| Acalypta elegans | Lace Bug |
| Acalypta lillianis | True Bug |
| Acalypta parvula | True Bug |
| Acalypta saundersi | True Bug |
| Acalyptus carpini | Snout Beetle |
| Acanthephyra curtirostris | Peaked Shrimp |
| Acanthococcus greeni | True Bug |
| Acanthodoris brunnea | Brown Spiny Doris |
| Acanthodoris lutea | Yellow Dorid |
| Acantholeberis curvirostris | Water Flea |
| Acantholiparis caecus | Fanged Snailfish |
| Acantholiparis opercularis | Spiny Snailfish |
| Acantholomidea porosa | True Bug |
| Acantholycosa solituda | Thinlegged Wolf Spider |
| Acanthonotozoma rusanovae | Amphipod |
| Acanthonus armatus | Bony-eared Assfish |
| Acanthoscelides aureolus | Bean Weevil |
| Acanthoscelides fraterculus | Bean Weevil |
| Acanthoscelides obtectus | Bean Weevil |
| Acanthoscelides pauperculus | Bean Weevil |
| Acanthoscelides pullus | Bean Weevil |
| Acanthoscelidius acephalus | Snout Beetle |
| Acasis viridata | Moth |
| Accedomoera melanopthalma | Amphipod |
| Accedomoera vagor | Amphipod |
| Acentrella insignificans | Mayfly |
| Aceroides latipes | Amphipod |
| Achrotile distincta | True Bug |
| Achrotile stylata | True Bug |
| Achrotile subarctica | True Bug |
| Acidostoma hancocki | Amphipod |
| Acidota quadrata | Rove Beetle |
| Acinopterus viridis | True Bug |
| Acirsa costulata | Chalky Wentletrap |
| Acleris aenigmana | Moth |
| Acleris bowmanana | Moth |
| Acleris braunana | Moth |
| Acleris britannia | Moth |
| Acleris caliginosana | Moth |
| Acleris celiana | Moth |
| Acleris comariana | Moth |
| Acleris cornana | Moth |
| Acleris emargana | Moth |
| Acleris forbesana | Moth |
| Acleris fragariana | Moth |
| Acleris fuscana | Moth |
| Acleris hudsoniana | Moth |
| Acleris implexana | Moth |
| Acleris lipsiana | Moth |
| Acleris logiana | Moth |
| Acleris maccana | Moth |
| Acleris maximana | Moth |
| Acleris nigrolinea | Moth |
| Acleris okanagana | Moth |
| Acleris paracinderella | Moth |
| Acleris ptychogrammos | Moth |
| Acleris robinsoniana | Moth |
| Acleris schalleriana | Moth |
| Acleris semiannula | Moth |
| Acleris senescens | Moth |
| Acleris variana | Moth |
| Aclypea bituberosa | Carrion Beetle |
| Acmaeodera idahoensis | Jewel Beetle |
| Acmaeopsoides rufulus | Longhorned Beetle |
| Acolpenteron catostomi | Parasite |
| Acompocoris lepidus | True Bug |
| Acontia areli | Moth |
| Acontia major | Moth |
| Acopa perpallida | Moth |
| Acrobasis betulella | Moth |
| Acrocheilus aleutaceus | Chiselmouth |
| Acrocirrus columbianus | Polychaete Worm |
| Acrocirrus occipitalis | Polychaete Worm |
| Acromacer bombifrons | Pine Flower Weevil |
| Acronicta cyanescens | Moth |
| Acronicta furcifera | Forked Dagger Moth |
| Acronicta hasta | Speared Dagger Moth |
| Acronicta impressa | Willow Dagger Moth |
| Acronicta lanceolaria | Lanceolatre Dagger Moth |
| Acronicta mansueta | Gentle Dagger Moth |
| Acronicta marmorata | Marble Dagger Moth |
| Acronicta quadrata | Quadrate Dagger Moth |
| Acronicta strigulata | Dagger Moth |
| Acrotrichis castanea | Feather-Winged Beetle |
| Acrotrichis cognata | Feather-Winged Beetle |
| Acrotrichis diffinis | Feather-Winged Beetle |
| Acrotrichis henrici | Feather-Winged Beetle |
| Acrotrichis insularis | Feather-Winged Beetle |
| Acrotrichis josephi | Feather-Winged Beetle |
| Acrotrichis parallelopipeda | Feather-Winged Beetle |
| Acrotrichis vicina | Feather-Winged Beetle |
| Acrotrichis xanthocera | Feather-Winged Beetle |
| Acrulia crenulata | Rove Beetle |
| Acrulia tumidula | Rove Beetle |
| Actebia balanitis | Moth |
| Acteocina culcitella | Pillow Barrel-Bubble |
| Acteocina eximia | Intermediate Barrel-Bubble |
| Acteocina inculta | Rude Barrel-Bubble |
| Actidium crotchianum | Feather-Winged Beetle |
| Actinobdella triannulata | Freshwater Leech |
| Aculepeira packardi | Orbweaver |
| Acupalpus carus | Ground Beetle |
| Acupalpus meridianus | Ground Beetle |
| Acylophorus pronus | Rove Beetle |
| Acyrthosiphon caraganae | Caragana Aphid |
| Acyrthosiphon malvae malvae | Aphid |
| Acyrthosiphon malvae rogersi | Aphid |
| Acyrthosiphon pisum | Aphid |
| Acyrthosiphon pseudodirhodus | Aphid |
| Acyrthosiphon purshiae | Aphid |
| Adaina cinerascens | Moth |
| Adaina montanus | Moth |
| Adalaria evincta | Crowned Dorid |
| Adalaria jannae | Nudibranch |
| Adalaria proxima | Yellow False Doris |
| Adalia bipunctata | Twospotted Lady Beetle |
| Adela purpurea | Moth |
| Adelges abietis | True Bug |
| Adelges lariciatus | True Bug |
| Adelges nordmannianae | True Bug |
| Adelges oregonensis | True Bug |
| Adelges piceae | True Bug |
| Adelges tsugae | True Bug |
| Adelphocoris rapidus | True Bug |
| Adelphocoris superbus | True Bug |
| Adita chionanthi | Moth |
| Admete couthouyi | Northern Admete |
| Admetovis oxymorus | Moth |
| Admetovis similaris | Moth |
| Adocia dubia | Sponge |
| Adocia gellindra | Sponge |
| Adontorhina cyclia | Circle Axinopsid |
| Adontorhina sphaericosa | Inflated Axinopsid |
| Adota maritima | Rove Beetle |
| Adula californiensis | California Datemussel |
| Aedes aloponotum | Mosquito |
| Aedes campestris | Mosquito |
| Aedes canadensis | Mosquito |
| Aedes cataphylla | Mosquito |
| Aedes communis | Mosquito |
| Aedes diantaeus | Mosquito |
| Aedes euedes | Mosquito |
| Aedes excrucians | Mosquito |
| Aedes fitchii | Mosquito |
| Aedes flavescens | Mosquito |
| Aedes hendersoni | Mosquito |
| Aedes hexodontus | Mosquito |
| Aedes impiger | Mosquito |
| Aedes implicatus | Mosquito |
| Aedes increpitus | Mosquito |
| Aedes intrudens | Mosquito |
| Aedes japonicus | Asian Bush Mosquito |
| Aedes melanimon | Mosquito |
| Aedes mercurator | Mosquito |
| Aedes nevadensis | Mosquito |
| Aedes nigripes | Mosquito |
| Aedes pionips | Mosquito |
| Aedes provocans | Mosquito |
| Aedes pullatus | Mosquito |
| Aedes riparius | Mosquito |
| Aedes spencerii | Mosquito |
| Aedes sticticus | Mosquito |
| Aedes vexans | Mosquito |
| Aega plebia | Isopod |
| Aega symmetrica | Isopod |
| Aegialia blanchardi | Scarab Beetle |
| Aegialia crassa | Scarab Beetle |
| Aegialia criddlei | Scarab Beetle |
| Aegialia cylindrica | Scarab Beetle |
| Aegialia lacustris | Scarab Beetle |
| Aegialia montana | Scarab Beetle |
| Aegialia opaca | Scarab Beetle |
| Aegialia rufescens | Scarab Beetle |
| Aegialia terminalis | Scarab Beetle |
| Aegialites californicus | Narrow-Waisted Bark Beetle |
| Aelia americana | True Bug |
| Aeolothrips fasciatus | Thrip |
| Aeolus mellillus comis | Click Beetle |
| Aeropedellus clavatus | Club-horned Grasshopper |
| Aeropsis fulva | Oblong Sea Urchin |
| Aetea anguina | Bryozoa |
| Aetea ligulata | Bryozoa |
| Aetea truncata | Bryozoa |
| Aethes deutschiana | Moth |
| Aethes promptana | Moth |
| Aethes rutilana | Moth |
| Aethes smeathmanniana | Moth |
| Agabinus glabrellus | Predacious Diving Beetle |
| Agabus adpressus | Predacious Diving Beetle |
| Agabus ajax | Predacious Diving Beetle |
| Agabus ambiguus | Predacious Diving Beetle |
| Agabus approximatus | Predacious Diving Beetle |
| Agabus arcticus | Predacious Diving Beetle |
| Agabus audeni | Predacious Diving Beetle |
| Agabus bicolor | Predacious Diving Beetle |
| Agabus bifarius | Predacious Diving Beetle |
| Agabus bjorkmanae | Predacious Diving Beetle |
| Agabus clavicornis | Predacious Diving Beetle |
| Agabus confertus | Predacious Diving Beetle |
| Agabus confinis | Predacious Diving Beetle |
| Agabus coxalis | Predacious Diving Beetle |
| Agabus discolor | Predacious Diving Beetle |
| Agabus discors | Predacious Diving Beetle |
| Agabus elongatus | Predacious Diving Beetle |
| Agabus erichsoni | Predacious Diving Beetle |
| Agabus fuscipennis | Predacious Diving Beetle |
| Agabus infuscatus | Predacious Diving Beetle |
| Agabus inscriptus | Predacious Diving Beetle |
| Agabus leptapsis | Predacious Diving Beetle |
| Agabus lugens | Predacious Diving Beetle |
| Agabus nectris | Predacious Diving Beetle |
| Agabus oblongulus | Predacious Diving Beetle |
| Agabus opacus | Predacious Diving Beetle |
| Agabus phaeopterus | Predacious Diving Beetle |
| Agabus pisobius | Predacious Diving Beetle |
| Agabus semipunctatus | Predacious Diving Beetle |
| Agabus smithi | Predacious Diving Beetle |
| Agabus thomsoni | Predacious Diving Beetle |
| Agabus verisimilis | Predacious Diving Beetle |
| Agabus wasastjernae | Predacious Diving Beetle |
| Agallia quadripunctata | True Bug |
| Agalliopsis abietaria | True Bug |
| Agalliopsis ancistra | True Bug |
| Agalma elegans | Jellyfish |
| Agapetus taho | Caddisfly |
| Agasphaerops niger | Snout Beetle |
| Agathidium angulare | Round Fungus Beetle |
| Agathidium californicum | Round Fungus Beetle |
| Agathidium cavisternum | Round Fungus Beetle |
| Agathidium columbianum | Round Fungus Beetle |
| Agathidium concinnum | Round Fungus Beetle |
| Agathidium conjunctum | Round Fungus Beetle |
| Agathidium contiguum | Round Fungus Beetle |
| Agathidium depressum | Round Fungus Beetle |
| Agathidium maculosum | Round Fungus Beetle |
| Agathidium obtusum | Round Fungus Beetle |
| Agelenopsis actuosa | Grass Spider |
| Agelenopsis oklahoma | Grass Spider |
| Agelenopsis oregonensis | Grass Spider |
| Agelenopsis utahana | Grass Spider |
| Agenotettix deorum | White-whiskered Grasshopper |
| Aglaja ocelligera | Spotted Aglajid |
| Aglaophamus rubella anops | Polychaete Worm |
| Aglossa cacamica | Moth |
| Aglossa caprealis | Moth |
| Agnocoris rubicundus | True Bug |
| Agnocoris utahensis | True Bug |
| Agnorisma bugrai | Moth |
| Agnyphantes arboreus | Spider |
| Agonopterix antennariella | Moth |
| Agonopterix canadensis | Moth |
| Agonopterix clarkei | Moth |
| Agonopterix flavicomella | Moth |
| Agonopterix gelidella | Moth |
| Agonopterix rosaciliella | Moth |
| Agonum affine | Ground Beetle |
| Agonum belleri | Ground Beetle |
| Agonum bicolor | Ground Beetle |
| Agonum consimile | Ground Beetle |
| Agonum decorum | Ground Beetle |
| Agonum exaratum | Ground Beetle |
| Agonum harrisii | Ground Beetle |
| Agonum melanarium | Ground Beetle |
| Agonum metallescens | Ground Beetle |
| Agonum mutatum | Ground Beetle |
| Agonum picicornoides | Ground Beetle |
| Agonum retractum | Ground Beetle |
| Agonum simile | Ground Beetle |
| Agonum subsericeum | Ground Beetle |
| Agonum variolatum | Ground Beetle |
| Agraylea multipunctata | Caddisfly |
| Agraylea saltesea | Caddisfly |
| Agrilus anxius | Bronze Birch Borer |
| Agrilus granulatus populi | Jewel Beetles |
| Agriotella columbiana | Click Beetle |
| Agriotella occidentalis | Click Beetle |
| Agriotes apicalis | Click Beetle |
| Agriotes criddlei | Click Beetle |
| Agriotes ferrugineipennis | Click Beetle |
| Agriotes hoodi | Click Beetle |
| Agriotes limosus | Click Beetle |
| Agriotes lineatus | Lined Click Beetle |
| Agriotes obscurus | Click Beetle |
| Agriotes opaculus | Click Beetle |
| Agriotes sparsus | Click Beetle |
| Agriotes stabilis | Click Beetle |
| Agriotes thevenetti | Click Beetle |
| Agriphila attenuatus | Moth |
| Agriphila plumbifimbriellus | Moth |
| Agriphila straminella | Moth |
| Agriphila vulgivagellus | Moth |
| Agrius cingulata | Moth |
| Agrochola purpurea | Moth |
| Agroeca ornata | Liocranid Sac Spider |
| Agroeca pratensis | Liocranid Sac Spider |
| Agronus carri | Snout Beetle |
| Agrotis antica | Moth |
| Agrotis gravis | Moth |
| Agrotis ruta | Moth |
| Agrotis venerabilis | Moth |
| Agrypnia deflata | Caddisfly |
| Agrypnia sahlbergi | Caddisfly |
| Agrypnia vestita | Large Caddisfly |
| Agulla arizonica | Snakefly |
| Agyneta allosubtilis | Sheetweb Spider |
| Agyneta aquila | Sheetweb Spider |
| Agyneta bucklei | Sheetweb Spider |
| Agyneta danielbelangeri | Sheetweb Spider |
| Agyneta darrelli | Sheetweb Spider |
| Agyneta emertoni | Dwarf Spider |
| Agyneta fabra | Dwarf Spider |
| Agyneta fillmorana | Dwarf Spider |
| Agyneta flibuscrocus | Sheetweb Spider |
| Agyneta fratrella | Sheetweb Spider |
| Agyneta lophophor | Sheetweb Spider |
| Agyneta manni | Sheetweb Spider |
| Agyneta maritima | Sheetweb Spider |
| Agyneta nigripes | Sheetweb Spider |
| Agyneta olivacea | Sheetweb Spider |
| Agyneta ordinaria | Dwarf Spider |
| Agyneta perspicua | Sheetweb Spider |
| Agyneta protrudens | Dwarf Spider |
| Agyneta simplex | Dwarf Spider |
| Agyneta uta | Sheetweb Spider |
| Agyneta watertoni | Sheetweb Spider |
| Agyrtes longulus | Primitive Carrion Beetle |
| Ahasverus advena | Foreign Grain Beetle |
| Airora aequalis | Bark-Gnawing Beetle |
| Akiodoris salacia | Sea Goddess Dorid |
| Alaus melanops | Click Beetle |
| Alcyonidium gelatinosum | Gelatinous Leather Bryozoan |
| Alcyonidium mammillatum | Bryozoa |
| Alderina brevispina | Bryozoa |
| Aldisa albomarginata | White-lined Aldisa |
| Aldisa cooperi | Cooper's Aldisa |
| Aldisa tara | Tara's Aldisa |
| Aldrovandia oleosa | Halosaur |
| Aleochara assiniboin | Rove Beetle |
| Aleochara bilineata | Rove Beetle |
| Aleochara bimaculata | Rove Beetle |
| Aleochara castaneipennis | Rove Beetle |
| Aleochara curtidens | Rove Beetle |
| Aleochara curtula | Rove Beetle |
| Aleochara fumata | Rove Beetle |
| Aleochara gracilicornis | Rove Beetle |
| Aleochara lacertina | Rove Beetle |
| Aleochara lanuginosa | Rove Beetle |
| Aleochara littoralis | Rove Beetle |
| Aleochara pacifica | Rove Beetle |
| Aleochara rubricalis | Rove Beetle |
| Aleochara suffusa | Rove Beetle |
| Aleochara sulcicollis | Rove Beetle |
| Aleochara tahoensis | Rove Beetle |
| Aleochara verna | Rove Beetle |
| Aleochara villosa | Rove Beetle |
| Alepocephalus tenebrosus | Slickhead |
| Aletopauropus lentus | Pauropod |
| Aleuroplatus berbericolus | True Bug |
| Aleyrodes spiraeoides | True Bug |
| Alia tuberosa | Variegate Dovesnail |
| Aligia californica | True Bug |
| Alle alle | Dovekie |
| Allintoshius nycticeius | Parasite |
| Allocosmoecus partitus | Caddisfly |
| Allocreadium isoporum | Parasite |
| Allocyttus folletti | Oxeye Oreo |
| Allolumpenus hypochromus | Y-Prickleback |
| Allomengea dentisetis | Sheetweb Spider |
| Allomyia bifosa | Caddisfly |
| Allomyia cascadis | Caddisfly |
| Allomyia cidoipes | Caddisfly |
| Allomyia tripunctata | Caddisfly |
| Alloniscus perconvexus | Isopod |
| Allopauropus broelemanni | Pauropod |
| Allopauropus marshalli | Pauropod |
| Alloperla delicata | Stonefly |
| Alloperla fraterna | Stonefly |
| Alloperla medveda | Stonefly |
| Alloperla serrata | Stonefly |
| Alloperla severa | Stonefly |
| Allopoda californica | False Flower Beetle |
| Allorchestes bella bella | Amphipod |
| Allorchestes pacifica | Amphipod |
| Allorchestes parva | Amphipod |
| Allorchestes urocarinata | Amphipod |
| Allosirocalus angulatus | Snout Beetle |
| Allosirocalus disturbatus | Snout Beetle |
| Allosmerus elongatus | Whitebait Smelt |
| Allygus mixtus | True Bug |
| Alniphagus hirsutus | Bark And Ambrosia Beetle |
| Alonella nana | Water Flea |
| Alopecosa aculeata | Wolf Spider |
| Alopecosa pictilis | Wolf Spider |
| Alopias vulpinus | Thresher Shark |
| Alosa sapidissima | American Shad |
| Alphitobius diaperinus | Lesser Mealworm |
| Alphitobius laevigatus | Black Fungus Beetle |
| Altica ambiens | Alder Flea Beetle |
| Altica bimarginata | Leaf Beetle |
| Altica caurina | Leaf Beetle |
| Altica corni | Leaf Beetle |
| Altica prasina | Leaf Beetle |
| Altica probata | Leaf Beetle |
| Altica tincta | Leaf Beetle |
| Altica tombacina | Leaf Beetle |
| Alydus calcaratus | True Bug |
| Alydus conspersus conspersus | True Bug |
| Alydus conspersus infuscatus | True Bug |
| Alydus eurinus eurinus | True Bug |
| Alydus scutellatus | True Bug |
| Alypia octomaculata | Eight-spotted Forester |
| Alypia ridingsii | Mountain Forester |
| Amaena occidentalis | Polychaete Worm |
| Amage anops | Polychaete Worm |
| Amalus scortillum | Snout Beetle |
| Amaplectoides pressus | Moth |
| Amara alpina | Ground Beetle |
| Amara apricaria | Ground Beetle |
| Amara aurata | Ground Beetle |
| Amara avida | Ground Beetle |
| Amara blanchardi | Ground Beetle |
| Amara bokori | Ground Beetle |
| Amara californica | Ground Beetle |
| Amara carinata | Ground Beetle |
| Amara coelebs | Ground Beetle |
| Amara conflata | Ground Beetle |
| Amara confusa | Ground Beetle |
| Amara convexa | Ground Beetle |
| Amara cupreolata | Ground Beetle |
| Amara discors | Ground Beetle |
| Amara ellipsis | Ground Beetle |
| Amara emancipata | Ground Beetle |
| Amara erratica | Ground Beetle |
| Amara familiaris | Ground Beetle |
| Amara farcta | Ground Beetle |
| Amara glacialis | Ground Beetle |
| Amara hyperborea | Ground Beetle |
| Amara lacustris | Ground Beetle |
| Amara laevipennis | Ground Beetle |
| Amara latior | Ground Beetle |
| Amara littoralis | Ground Beetle |
| Amara longula | Ground Beetle |
| Amara lunicollis | Ground Beetle |
| Amara musculis | Ground Beetle |
| Amara obesa | Ground Beetle |
| Amara pallipes | Ground Beetle |
| Amara patruelis | Ground Beetle |
| Amara pseudobrunnea | Ground Beetle |
| Amara quenseli | Ground Beetle |
| Amara sanjuanensis | Ground Beetle |
| Amara scitula | Ground Beetle |
| Amara sinuosa | Ground Beetle |
| Amara thoracica | Ground Beetle |
| Amara torrida | Ground Beetle |
| Amaurobius borealis | Hackledmesh Weaver |
| Ambesa laetella | Moth |
| Ambesa walsinghami | Moth |
| Amblopusa borealis | Rove Beetle |
| Amblopusa brevipes | Rove Beetle |
| Amblyderus obesus | Antlike Flower Beetle |
| Amblyderus pallens | Antlike Flower Beetle |
| Amblyopone oregonense | Dracula Ant |
| Amblyptilia pica | Moth |
| Amblyraja badia | Broad Skate |
| Amblysellus grex | True Bug |
| Amblysellus punctatus | True Bug |
| Amblysellus wyomus | True Bug |
| Amblytylus nasutus | True Bug |
| Ameiurus natalis | Yellow Bullhead |
| Ameletus celer | Mayfly |
| Ameletus cooki | Mayfly |
| Ameletus oregonensis | Mayfly |
| Ameletus pritchardi | Mayfly |
| Ameletus shepherdi | Mayfly |
| Ameletus similior | Mayfly |
| Ameletus sparsatus | Mayfly |
| Ameletus subnotatus | Mayfly |
| Ameletus suffusus | Mayfly |
| Ameletus validus | Mayfly |
| Ameletus vancouverensis | Mayfly |
| Ameletus velox | Mayfly |
| Ameletus vernalis | Mayfly |
| Americhelidium pectinatum | Amphipod |
| Americhelidium rectipalmum | Amphipod |
| Americhelidium setosum | Amphipod |
| Americhelidium shoemakeri | Amphipod |
| Americhelidium variabilum | Amphipod |
| Amerocerus confusus | Soft-Winged Flower Beetle |
| Amerocerus glabratus | Soft-Winged Flower Beetle |
| Amerocerus olympianus | Soft-Winged Flower Beetle |
| Amerocerus plenus | Soft-Winged Flower Beetle |
| Amerocerus provincialis | Soft-Winged Flower Beetle |
| Amerocerus quadricollis | Soft-Winged Flower Beetle |
| Amerocerus robustus | Soft-Winged Flower Beetle |
| Ametor latus | Water Scavenger Beetle |
| Amiantis callosa | White Venus |
| Amidostomum acutum | Parasite |
| Amidostomum anseris | Parasite |
| Amidostomum cygni | Parasite |
| Amidostomum fulicae | Parasite |
| Amidostomum spatulatum | Parasite |
| Amiocentrus aspilus | Caddisfly |
| Amnestus pallidus | True Bug |
| Amorbia humerosana | Moth |
| Ampedus antracinus | Click Beetle |
| Ampedus apicatus | Click Beetle |
| Ampedus atripennis | Click Beetle |
| Ampedus deletus | Click Beetle |
| Ampedus dimidiatus | Click Beetle |
| Ampedus laurentinus | Click Beetle |
| Ampedus melinus | Click Beetle |
| Ampedus nigrinus | Click Beetle |
| Ampedus occidentalis | Click Beetle |
| Ampedus phelpsi | Click Beetle |
| Ampedus phoenicopterus | Click Beetle |
| Ampedus quebecensis | Click Beetle |
| Ampedus subtilis | Click Beetle |
| Ampedus varipilis | Click Beetle |
| Ampelisca birulai | Amphipod |
| Ampelisca brevisimulata | Amphipod |
| Ampelisca careyi | Amphipod |
| Ampelisca cristata | Amphipod |
| Ampelisca hancocki | Amphipod |
| Ampelisca pugetica | Amphipod |
| Ampelisca unsocolae | Amphipod |
| Ampharete acutifrons | Polychaete Worm |
| Ampharete finmarchica | Polychaete Worm |
| Ampharete goesi | Polychaete Worm |
| Ampharete labrops | Polychaete Worm |
| Amphicercidus pulverulens | True Bug |
| Amphichroum floribundum | Rove Beetle |
| Amphicosmoecus canax | Caddisfly |
| Amphicteis florida | Polychaete Worm |
| Amphicteis mucronata | Polychaete Worm |
| Amphicteis scaphobranchiata | Polychaete Worm |
| Amphictene moorei | Polychaete Worm |
| Amphilectus laxus | Sponge |
| Amphilectus vancouverensis | Sponge |
| Amphilepis patens | Brittle Star |
| Amphilina bipunctata | Parasite |
| Amphinema platyhedos | Jellyfish |
| Amphinemura linda | Stonefly |
| Amphiodia urtica | Long-Armed Burrowing Brittle Star |
| Amphiophiura bullata pacifica | Scaly Brittle Star |
| Amphiophiura superba | Scaly Brittle Star |
| Amphiopholis pugetana | Long-Armed Burrowing Brittle Star |
| Amphiopholis squamata | Long-Armed Burrowing Brittle Star |
| Amphioplus euryaspis | Long-Armed Burrowing Brittle Star |
| Amphioplus macraspis | Long-Armed Burrowing Brittle Star |
| Amphioplus strongyloplax | Long-Armed Burrowing Brittle Star |
| Amphipoea americana | Moth |
| Amphipoea pacifica | Moth |
| Amphiporus cruenatus | Ribbon Worm |
| Amphiporus gelatinosus | Ribbon Worm |
| Amphiporus imparispinosus | Ribbon Worm |
| Amphiporus tigrinus | Ribbon Worm |
| Amphipyra glabella | Moth |
| Amphisamytha bioculata | Polychaete Worm |
| Amphissa reticulata | Reticulate Amphissa |
| Amphissa versicolor | Variegate Amphissa |
| Amphistichus rhodoterus | Redtail Surfperch |
| Amphitrite cirrata | Polychaete Worm |
| Amphiura arcystata | Long-Armed Burrowing Brittle Star |
| Amphiura carchara | Long-Armed Burrowing Brittle Star |
| Amphiura diomedeae | Long-Armed Burrowing Brittle Star |
| Amphivectura monticola | Soft-Winged Flower Beetle |
| Amphizoa lecontei | Trout Stream Beetle |
| Amphorophora agathonica | True Bug |
| Amphorophora forbesi | True Bug |
| Amphorophora geranii | True Bug |
| Amphorophora parviflori | True Bug |
| Amphorophora rossi | True Bug |
| Amphorophora rubitoxica | True Bug |
| Amphorophora stachyophila | True Bug |
| Amphorophora tigwatensa | True Bug |
| Amphorophora urtica | True Bug |
| Ampithoe dalli | Amphipod |
| Ampithoe kussakini | Amphipod |
| Ampithoe lacerota | Amphipod |
| Ampithoe plumulosa | Amphipod |
| Ampithoe sectimanus | Amphipod |
| Ampithoe simulans | Amphipod |
| Ampithoe valida | Amphipod |
| Amplicephalus inimicus | True Bug |
| Amplicephalus montanus | True Bug |
| Amplicephalus nebulosus | True Bug |
| Anaata brepha | Sponge |
| Anaata spongigartina    | Sponge |
| Anacaena limbata | Water Scavenger Beetle |
| Anacampsis fragariella | Moth |
| Anacampsis innocuella | Moth |
| Anacampsis niveopulvella | Moth |
| Anagapetus bernea | Caddisfly |
| Anagapetus debilis | Caddisfly |
| Anagapetus hoodi | Caddisfly |
| Anagrapha falcifera | Moth |
| Anaitides citrina | Polychaete Worm |
| Anaitides groenlandica | Polychaete Worm |
| Anaitides maculata | Polychaete Worm |
| Anaitides madeirensis | Polychaete Worm |
| Anaitides mucosa | Polychaete Worm |
| Anametis granulata | Snout Beetle |
| Anaptus major | True Bug |
| Anarsia lineatella | Moth |
| Anarta columbica | Moth |
| Anarta crotchii | Moth |
| Anarta decepta | Moth |
| Anarta hamata | Moth |
| Anarta montanica | Moth |
| Anarta mutata | Moth |
| Anarta oregonica | Moth |
| Anas formosa | Baikal Teal |
| Anaspis atrata | False Flower Beetle |
| Anaspis duryi | False Flower Beetle |
| Anaspis flavipennis | False Flower Beetle |
| Anaspis nigrina | False Flower Beetle |
| Anaspis rayi | False Flower Beetle |
| Anaspis rufa | False Flower Beetle |
| Anaspis seposita | False Flower Beetle |
| Anaspis sericea | False Flower Beetle |
| Anathix aggressa | Moth |
| Anathix puta | Moth |
| Anatis lecontei | Lady Beetle |
| Anatis mali | Lady Beetle |
| Anatis rathvoni | Lady Beetle |
| Anatralata versicolor | Moth |
| Anavitrinella addendaria | Moth |
| Anchastus anthrax | Click Beetle |
| Anchastus cinereipennis | Click Beetle |
| Ancula gibbosa | Atlantic Ancula |
| Ancylis apicana | Moth |
| Ancylis columbiana | Moth |
| Ancylis comptana | Moth |
| Ancylis diminutana | Moth |
| Ancylis discigerana | Moth |
| Ancylis laciniana | Moth |
| Ancylis mediofasciana | Moth |
| Ancylis mira | Moth |
| Ancylis nubeculana | Moth |
| Ancylis pacificana | Moth |
| Ancylis simuloides | Moth |
| Ancylis subaequana | Moth |
| Ancylis tenebrica | Moth |
| Ancylis unguicella | Moth |
| Ancyracanthopsis bendelli | Parasite |
| Ancyracanthopsis coronata | Parasite |
| Andrenosoma fulvicaudum | Robber Fly |
| Andropolia diversilineata | Cutworm Moth |
| Andropolia epichysis | Moth |
| Anelastes druryi | False Click Beetle |
| Anelpistus canadensis | False Longhorn Beetle |
| Anepsiota quadricollis | Rove Beetle |
| Anepsiota terminalis | Rove Beetle |
| Aneurus borealis | True Bug |
| Aneurus inconstans | True Bug |
| Aneurus simplex | True Bug |
| Angulosaccus tenuis | Deep-Sea Hermit Parasitic Barnacle |
| Anhimella contrahens | Cutworm Moth |
| Anhimella pacifica | Cutworm Moth |
| Anhimella perbrunnea | Cutworm Moth |
| Anicla exuberans | Moth |
| Anicla tepperi | Moth |
| Anidolyta spongotheras | Limpet-Like Yellow-Green Seaslug |
| Anisakis simplex | Parasite |
| Anisococcus oregonensis | True Bug |
| Anisococcus quercus | True Bug |
| Anisodactylus amaroides | Ground Beetle |
| Anisodactylus californicus | Ground Beetle |
| Anisodactylus harrisii | Ground Beetle |
| Anisodactylus kirbyi | Ground Beetle |
| Anisodactylus nigrita | Ground Beetle |
| Anisodactylus nivalis | Ground Beetle |
| Anisodactylus similis | Ground Beetle |
| Anisogammarus epistomus | Amphipod |
| Anisogammarus pugettensis | Amphipod |
| Anisogammarus slatteryi | Amphipod |
| Anisorchis opisthorchis | Parasite |
| Anisostena californica | Leaf Beetle |
| Anisostena nigrita | Leaf Beetle |
| Anisotoma amica | Round Fungus Beetle |
| Anisotoma confusa | Round Fungus Beetle |
| Anisotoma discolor | Round Fungus Beetle |
| Anisotoma errans | Round Fungus Beetle |
| Anisotoma globososa | Round Fungus Beetle |
| Anisotoma humeralis | Round Fungus Beetle |
| Anisotoma nevadensis | Round Fungus Beetle |
| Annaphila danistica | Cutworm Moth |
| Annaphila decia | Cutworm Moth |
| Anobium punctatum | Furniture Beetle |
| Anobothrus gracilis | Polychaete Worm |
| Anogdus fusciclavus | Round Fungus Beetle |
| Anogdus insolitus | Round Fungus Beetle |
| Anogdus mirabilis | Round Fungus Beetle |
| Anogdus potens | Round Fungus Beetle |
| Anonchohaptor anomulum | Parasite |
| Anonyx lilljeborgi | Amphipod |
| Anonyx nugax | Amphipod |
| Anopheles freeborni | Mosquito |
| Anopheles punctipennis | Mosquito |
| Anoplagonus inermis | Smooth Alligatorfish |
| Anoplogaster cornuta | Fangtooth |
| Anoplonyx luteipes | Threelined Larch Sawfly |
| Anoscopus albifrons | True Bug |
| Anoscopus albiger | True Bug |
| Anoscopus serratulae | True Bug |
| Anotopterus nikparini | North Pacific Daggertooth |
| Anotylus niger | Rove Beetle |
| Anotylus nitidulus | Rove Beetle |
| Anotylus rugosus | Rove Beetle |
| Anotylus sobrinus | Rove Beetle |
| Anotylus tetracarinatus | Rove Beetle |
| Antarctophthirius microchir | Louse |
| Antherophagus ochraceus | Silken Fungus Beetle |
| Antherophagus pallidivestis | Silken Fungus Beetle |
| Antherophagus suturalis | Silken Fungus Beetle |
| Anthicus bellulus | Antlike Flower Beetle |
| Anthicus biguttulus | Antlike Flower Beetle |
| Anthicus cervinus | Antlike Flower Beetle |
| Anthicus coracinus | Antlike Flower Beetle |
| Anthicus cribratus | Antlike Flower Beetle |
| Anthicus ephippium | Antlike Flower Beetle |
| Anthicus flavicans | Antlike Flower Beetle |
| Anthicus hastatus | Antlike Flower Beetle |
| Anthicus lecontei | Antlike Flower Beetle |
| Anthicus lutulentus | Antlike Flower Beetle |
| Anthicus nanus | Antlike Flower Beetle |
| Anthicus praeceps | Antlike Flower Beetle |
| Anthicus punctulatus | Antlike Flower Beetle |
| Antho illgi | Sponge |
| Antho karykina | Sponge |
| Antho lambei | Sponge |
| Anthoarcuata graceae  | Sponge |
| Anthobium clarki | Rove Beetle |
| Anthobium fimetarium | Rove Beetle |
| Anthobium occiduum | Rove Beetle |
| Anthobium reflexicolle | Rove Beetle |
| Anthobium sinuosum | Rove Beetle |
| Anthocoris confusus | True Bug |
| Anthocoris musculus | True Bug |
| Anthocoris nemoralis | True Bug |
| Anthocoris tomentosus | True Bug |
| Anthocoris whitei | True Bug |
| Anthocotyle merluccii | Parasite |
| Anthomastus glandiflora | Coral |
| Anthonomus confusus | Snout Beetle |
| Anthonomus consors | Snout Beetle |
| Anthonomus corvulus | Snout Beetle |
| Anthonomus deceptus | Snout Beetle |
| Anthonomus haematopus | Snout Beetle |
| Anthonomus hirtus | Snout Beetle |
| Anthonomus lecontei | Snout Beetle |
| Anthonomus melancholicus | Snout Beetle |
| Anthonomus molochinus | Snout Beetle |
| Anthonomus nebulosus | Snout Beetle |
| Anthonomus ochreopilosus | Snout Beetle |
| Anthonomus quadrigibbus | Apple Curculio |
| Anthonomus quesnelensis | Snout Beetle |
| Anthonomus rubidus | Snout Beetle |
| Anthonomus rubricus | Snout Beetle |
| Anthonomus signatus | Strawberry Bud Weevil |
| Anthonomus squamosus | Snout Beetle |
| Anthonomus suturalis | Snout Beetle |
| Anthophila alpinella | Moth |
| Anthoptilum grandiflorum | Pennatulacean |
| Anthoptilum murrayi | Pennatulacean |
| Anthrenus pimpinellae | Carpet Beetle |
| Anthrenus verbasci | Varied Carpet Beetle |
| Anthropoides virgo | Demoiselle Crane |
| Anthus cervinus | Red-Throated Pipit |
| Antimora microlepis | Pacific Flatnose |
| Antiplanes catalinae | Sea Snail |
| Antiplanes voyi | Perverse Turret |
| Antistea brunnea | Hahniid Spider |
| Antrechinus drygalskii perfidus | Sea Urchin |
| Antrodiaetus cerberus | Spider |
| Antrodiaetus hageni | Foldingdoor Spider |
| Antrodiaetus pugnax | Foldingdoor Spider |
| Anuropus bathypelagicus | Isopod |
| Anyphaena aperta | Ghost Spider |
| Anyphaena pacifica | Ghost Spider |
| Aoplonema princeps | True Bug |
| Aoplonema uhleri | True Bug |
| Aoroides columbiae | Amphipod |
| Aoroides exilis | Amphipod |
| Aoroides inermis | Amphipod |
| Aoroides intermedius | Amphipod |
| Aoroides spinosus | Amphipod |
| Apamea acera | Cutworm Moth |
| Apamea atriclava | Cutworm Moth |
| Apamea centralis | Cutworm Moth |
| Apamea cinefacta | Cutworm Moth |
| Apamea commoda | Cutworm Moth |
| Apamea contradicta | Cutworm Moth |
| Apamea inordinata | Cutworm Moth |
| Apamea lignicolora | Cutworm Moth |
| Apamea longula | Cutworm Moth |
| Apamea lutosa | Cutworm Moth |
| Apamea occidens | Moth |
| Apamea plutonia | Cutworm Moth |
| Apamea remissa | Cutworm Moth |
| Apamea sora | Cutworm Moth |
| Apamea spaldingi | Cutworm Moth |
| Apamea zeta | Cutworm Moth |
| Apatania alberta | Caddisfly |
| Apatania shoshone | Caddisfly |
| Apatania sorex | Caddisfly |
| Apatania zonella | Caddisfly |
| Apateticus bracteatus | True Bug |
| Aphaenogaster occidentalis | Ant |
| Aphalara persicariae | True Bug |
| Aphalara rumicis | True Bug |
| Aphanopus carbo | Black Scabbardfish |
| Apharetra californiae | Cutworm Moth |
| Apharetra dentata | Cutworm Moth |
| Aphelia alleniana | Moth |
| Aphelia. koebelei | Moth |
| Aphelochaeta multifilis | Polychaete Worm |
| Aphelochaeta parvus | Polychaete Worm |
| Aphelochaeta secundus | Polychaete Worm |
| Aphelochaeta serratisetis | Polychaete Worm |
| Aphenolia monogama | Sap-Feeding Beetle |
| Aphileta microtarsa | Spider |
| Aphileta misera | Sheetweb Spider |
| Aphis asclepiadis | True Bug |
| Aphis callunae | True Bug |
| Aphis canae | True Bug |
| Aphis ceanothi | True Bug |
| Aphis chani | True Bug |
| Aphis chloris | True Bug |
| Aphis chrysothamni | True Bug |
| Aphis coweni | True Bug |
| Aphis craccae | True Bug |
| Aphis craccivora | True Bug |
| Aphis cytisorum | True Bug |
| Aphis epilobii | True Bug |
| Aphis equiseticola | True Bug |
| Aphis farinosa | True Bug |
| Aphis forbesi | True Bug |
| Aphis galiiscabri | True Bug |
| Aphis genistae | True Bug |
| Aphis hederae | True Bug |
| Aphis helianthi | True Bug |
| Aphis hermistonii | True Bug |
| Aphis idaei | True Bug |
| Aphis lugentis | True Bug |
| Aphis lupini | True Bug |
| Aphis maculatae | True Bug |
| Aphis middletonii | True Bug |
| Aphis nasturtii | True Bug |
| Aphis neilliae | True Bug |
| Aphis nigratibialis | True Bug |
| Aphis oenotherae | True Bug |
| Aphis oregonensis | True Bug |
| Aphis pomi | True Bug |
| Aphis praeterita | True Bug |
| Aphis ribiensis | True Bug |
| Aphis rumicis | True Bug |
| Aphis salicariae | True Bug |
| Aphis sambuci | True Bug |
| Aphis sedi | True Bug |
| Aphis spiraephila | True Bug |
| Aphis vaccinii | True Bug |
| Aphis valerianae | True Bug |
| Aphis varians | True Bug |
| Aphis whiteshellensis | True Bug |
| Aphodius albertanus | Scarab Beetle |
| Aphodius aleutus | Scarab Beetle |
| Aphodius aquilonarius | Scarab Beetle |
| Aphodius bidentatus | Scarab Beetle |
| Aphodius borealis | Scarab Beetle |
| Aphodius browni | Scarab Beetle |
| Aphodius congregatus | Scarab Beetle |
| Aphodius corruptor | Scarab Beetle |
| Aphodius cribratulus | Scarab Beetle |
| Aphodius decipiens | Scarab Beetle |
| Aphodius distinctus | Scarab Beetle |
| Aphodius duplex | Scarab Beetle |
| Aphodius fossor | Scarab Beetle |
| Aphodius granarius | Scarab Beetle |
| Aphodius guttatus | Scarab Beetle |
| Aphodius hamatus hamatus | Scarab Beetle |
| Aphodius hirsutus | Scarab Beetle |
| Aphodius hyperboreus | Scarab Beetle |
| Aphodius leopardus | Scarab Beetle |
| Aphodius omissus omissus | Scarab Beetle |
| Aphodius omissus torpidus | Scarab Beetle |
| Aphodius opacus | Scarab Beetle |
| Aphodius pectoralis | Scarab Beetle |
| Aphodius phaeopterus | Scarab Beetle |
| Aphodius piceatus | Scarab Beetle |
| Aphodius pinguellus | Scarab Beetle |
| Aphodius richardsonae | Scarab Beetle |
| Aphodius rogersi | Scarab Beetle |
| Aphodius sigmoideus | Scarab Beetle |
| Aphodius subaeneus | Scarab Beetle |
| Aphodius tenellus | Scarab Beetle |
| Aphodius vittatus | Scarab Beetle |
| Aphorista laeta | Handsome Fungus Beetle |
| Aphrodes bicinctus | True Bug |
| Aphrodes costatus | True Bug |
| Aphrodite japonica | Japanese Sea-Mouse |
| Aphrodite negligens | Dishevelled Sea-Mouse |
| Aphrodite parva | Polychaete Worm |
| Aphrophora ampliata | True Bug |
| Aphrophora canadensis | True Bug |
| Aphrophora fulva | True Bug |
| Aphrophora gelida | True Bug |
| Aphrophora maculosa | True Bug |
| Aphrophora permutata | True Bug |
| Aphrophora princeps | True Bug |
| Aphrophora regina | True Bug |
| Aphthargelia symphoricarpi | True Bug |
| Apiomerus crassipes crassipes | True Bug |
| Apion alaskanum | Straight-Snouted Weevil |
| Apion antennatum | Straight-Snouted Weevil |
| Apion attenuatum | Straight-Snouted Weevil |
| Apion cavifrons | Straight-Snouted Weevil |
| Apion centrale | Straight-Snouted Weevil |
| Apion cyanitinctum | Straight-Snouted Weevil |
| Apion finitimum | Straight-Snouted Weevil |
| Apion longirostre | Straight-Snouted Weevil |
| Apion pennsylvanicum | Straight-Snouted Weevil |
| Apion proclive | Straight-Snouted Weevil |
| Apion punctinasum | Straight-Snouted Weevil |
| Apion simile | Straight-Snouted Weevil |
| Apistobranchus ornatus | Polychaete Worm |
| Apistobranchus tullbergi | Polychaete Worm |
| Aplectana lynae | Parasite |
| Aploderus linearis | Rove Beetle |
| Aploneura lentisci | True Bug |
| Apochthonius minimus | Pseudoscorpion |
| Apohyale anceps | Amphipod |
| Apohyale californica | Amphipod |
| Apohyale pugettensis | Amphipod |
| Apollophanes margareta | Running Crab Spider |
| Apolochus litoralis | Amphipod |
| Apolochus staudi | Amphipod |
| Apomyelois bistriatella | Moth |
| Aporocotyle macfarlani | Parasite |
| Aporocotyle theragrae | Parasite |
| Aporrectodea caliginosa | Pasture Worm |
| Aporrectodea limicola | Earthworm |
| Aporrectodea trapezoides | Southern Worm |
| Aporrectodea tuberculata | Canadian Worm |
| Apostenus ducati | Liocranid Sac Spider |
| Apote robusta | Robust Anabrus |
| Apotomis apateticana | Moth |
| Apotomis infida | Moth |
| Apotomis spinulana | Moth |
| Apotomis tertiana | Moth |
| Apotomops wellingtoniana | Moth |
| Appendiseta robiniae | True Bug |
| Apristus pugetanus | Ground Beetle |
| Apteroloma caraboides | Primitive Carrion Beetle |
| Apteroloma tenuicorne | Primitive Carrion Beetle |
| Apterona helicoidella | Moth |
| Aquarius nyctalis | True Bug |
| Aquarius remigis | True Bug |
| Arabella iricolor | Polychaete Worm |
| Aradus abbas | True Bug |
| Aradus antennalis | True Bug |
| Aradus approximatus | True Bug |
| Aradus behrensi | True Bug |
| Aradus blaisdelli | True Bug |
| Aradus coarctatus | True Bug |
| Aradus compressus | True Bug |
| Aradus debilis | True Bug |
| Aradus depictus | True Bug |
| Aradus falleni | True Bug |
| Aradus funestus | True Bug |
| Aradus fuscomaculatus | True Bug |
| Aradus heidemanni | True Bug |
| Aradus insolitus | True Bug |
| Aradus intectus | True Bug |
| Aradus kormilevi | True Bug |
| Aradus lugubris lugubris | True Bug |
| Aradus lugubris nigricornis | True Bug |
| Aradus medioximus | True Bug |
| Aradus paganicus | True Bug |
| Aradus parshleyi | True Bug |
| Aradus parvicornis | True Bug |
| Aradus persimilis | True Bug |
| Aradus proboscideus | True Bug |
| Aradus quadrilineatus | True Bug |
| Aradus similis | True Bug |
| Aradus taylori | True Bug |
| Aradus tuberculifer | True Bug |
| Aradus vadosus | True Bug |
| Araecerus fasciculatus | Coffee Bean Weevil |
| Araneus iviei | Angulate & Roundshouldered Orbweaver |
| Araneus montereyensis | Angulate & Roundshouldered Orbweaver |
| Araneus nordmanni | Angulate & Roundshouldered Orbweaver |
| Araneus washingtoni | Angulate & Roundshouldered Orbweaver |
| Araniella proxima | Spider |
| Arboridia betulaspera | True Bug |
| Arboridia insigna | True Bug |
| Arboridia plena | True Bug |
| Arboridia sinua | True Bug |
| Archanara oblonga | Cutworm Moth |
| Archanara subflava | Cutworm Moth |
| Archepandemis coniferana | Moth |
| Archiboreoiulus pallidus | Millipede |
| Archilestes californicus | California Spreadwing |
| Archips alberta | Moth |
| Archips eleagnana | Moth |
| Archips fervidana | Moth |
| Archips mortuana | Moth |
| Archips negundana | Moth |
| Archips oporana | Moth |
| Archips packardiana | Moth |
| Archips purpurana | Moth |
| Archips strianus | Moth |
| Archips tsuganus | Moth |
| Arctella lapponica | Meshweaver |
| Arctobius agelenoides | Hackledmesh Weaver |
| Arctocorisa convexa | True Bug |
| Arctocorisa sutilis | True Bug |
| Arctopora pulchella | Caddisfly |
| Arctorthezia occidentalis | True Bug |
| Arctosa alpigena | Wolf Spider |
| Arctosa emertoni | Wolf Spider |
| Arctosa insignita | Thinlegged Wolf Spider |
| Arctosa littoralis | Wolf Spider |
| Arctosa raptor | Wolf Spider |
| Arctosa rubicunda | Wolf Spider |
| Arcuatula senhousia | Date Mussel |
| Arcuphantes arcuatulus | Sheetweb Spider |
| Arcuphantes sylvaticus | Sheetweb Spider |
| Arcynopteryx compacta | Stonefly |
| Arenicola marina | Polychaete Worm |
| Argas cooleyi | Swallow Tick |
| Argas persicus | Bluebug |
| Argenna yakima | Meshweaver |
| Argissa hamatipes | Amphipod |
| Argulus pugettensis | Parasite |
| Argyresthia columbia | Moth |
| Argyresthia conjugella | Moth |
| Argyresthia cupressella | Moth |
| Argyresthia freyella | Moth |
| Argyresthia goedartella | Moth |
| Argyresthia laricella | Moth |
| Argyresthia monochromella | Moth |
| Argyresthia oreasella | Moth |
| Argyresthia pseudotsuga | Moth |
| Argyresthia pygmaeella | Moth |
| Argyresthia tsuga | Moth |
| Argyropelecus sladeni | Silvery Hatchetfish |
| Argyrotaenia citrana | Moth |
| Argyrotaenia franciscana | Moth |
| Argyrotaenia gogana | Moth |
| Argyrotaenia occultana | Moth |
| Argyrotaenia pinatubana | Moth |
| Argyrotaenia tabulana | Moth |
| Argyrotaenia velutinana | Moth |
| Arhyssus barberi | True Bug |
| Arhyssus crassus | True Bug |
| Arhyssus distinctus | True Bug |
| Arhyssus scutatus | True Bug |
| Arhyssus validus | True Bug |
| Aricidea assimilis | Polychaete Worm |
| Aricidea lopezi | Polychaete Worm |
| Aricidea minuta | Polychaete Worm |
| Aricidea neosuecica | Polychaete Worm |
| Aricidea quadrilobata | Polychaete Worm |
| Aricidea wassi | Polychaete Worm |
| Arion circumscriptus | Brown-Banded Arion |
| Arion distinctus | Darkface Arion |
| Arion hortensis | Garden Arion |
| Arion silvaticus | Forest Arion |
| Aristias pacificus | Amphipod |
| Aristias veleronis | Amphipod |
| Aristostomias scintillans | Shining Loosejaw |
| Aristotelia devexella | Moth |
| Aristotelia fungivorella | Moth |
| Aristotelia nigrobasiella | Moth |
| Armadillidium vulgare | Common Pill-bug |
| Armadilloniscus holmesi | Isopod |
| Aroga paraplutella | Moth |
| Arpedium cribratum | Rove Beetle |
| Arphia conspersa | Speckle-Winged Rangeland Grasshopper |
| Arta statalis | Moth |
| Artacama conifera | Polychaete Worm |
| Arthropoma cecili | Bryozoa |
| Artochia productifrons | Rove Beetle |
| Arytainilla spartiophila | True Bug |
| Asabellides lineata | Polychaete Worm |
| Asabellides sibirica | Polychaete Worm |
| Asagena americana | Spider |
| Asaphidion yukonense | Ground Beetle |
| Asbestopluma biserialis | Sponge |
| Ascaridia columbae | Parasite |
| Ascaridia galli | Parasite |
| Ascaridia hermaphrodita | Parasite |
| Ascaridia platyceri | Parasite |
| Ascaris suum | Parasite |
| Ascarophis sebastodis | Parasite |
| Ascelichthys rhodorus | Rosylip Sculpin |
| Aschedelphax hochae | True Bug |
| Asciodema obsoletum | True Bug |
| Asclera excavata | False Blister Beetle |
| Asclera nigra | False Blister Beetle |
| Asclerocheilus beringanus | Polychaete Worm |
| Asemobius caelatus | Rove Beetle |
| Asemoplus montanus | Montana Grasshopper |
| Asemum nitidum | Longhorned Beetle |
| Aseptis characta | Cutworm Moth |
| Asiphonaphis pruni | True Bug |
| Aspiculuris tetraptera | Parasite |
| Aspidophorodon longicaudus | True Bug |
| Astarte arctica | Astarte Clam |
| Astarte compacta | Compact Astarte |
| Astarte crenata | Crenulate Astarte |
| Astarte undata | Clam |
| Astenus cinctus | Rove Beetle |
| Astenus longiusculus | Rove Beetle |
| Asterodiaspis variolosa | True Bug |
| Asteronyx loveni | Snake Brittle Star |
| Astroschema sublaeve | Brittle Star |
| Astyris gausapata | Shaggy Dovesnail |
| Asymmetrura impositella | Moth |
| Asynarchus aldinus | Caddisfly |
| Asynarchus cinnamoneus | Caddisfly |
| Asynarchus lapponicus | Caddisfly |
| Asynarchus mutatus | Caddisfly |
| Atalopedes campestris campestris | Sachem |
| Atherinops affinis | Topsmelt |
| Atheroides serrulatus | True Bug |
| Athetalia metlakatlana | Rove Beetle |
| Athetalia nimia | Rove Beetle |
| Athetota atriventris | Rove Beetle |
| Athetota wickhami | Rove Beetle |
| Atholus bimaculatus | Clown Beetle |
| Atholus falli | Clown Beetle |
| Athous rufiventris rufiventris | Click Beetle |
| Athysanella acuticauda | True Bug |
| Athysanella attenuata | True Bug |
| Athysanella obesa | True Bug |
| Athysanella robusta | True Bug |
| Athysanella utahna | True Bug |
| Atimia hoppingi | Longhorned Beetle |
| Atomaria capitata | Silken Fungus Beetle |
| Atomaria ephippiata | Silken Fungus Beetle |
| Atomaria kamtschatica | Silken Fungus Beetle |
| Atomaria laetula | Silken Fungus Beetle |
| Atomaria longipennis | Silken Fungus Beetle |
| Atomaria melanica | Silken Fungus Beetle |
| Atomaria nubipennis | Silken Fungus Beetle |
| Atomaria planulata | Silken Fungus Beetle |
| Atomaria pusilla | Silken Fungus Beetle |
| Atomaria quadricollis | Silken Fungus Beetle |
| Atomaria stricticollis | Silken Fungus Beetle |
| Atomaria subdentata | Silken Fungus Beetle |
| Atomaria vespertina | Silken Fungus Beetle |
| Atomoscelis onustus | True Bug |
| Atractoscion nobilis | White Seabass |
| Atractotomus atricolor | True Bug |
| Atractotomus cercocarpi | True Bug |
| Atractotomus cooperi | True Bug |
| Atractotomus kolenatii | True Bug |
| Atractotomus mali | True Bug |
| Atractotomus rubidus | True Bug |
| Atrecus macrocephalus | Rove Beetle |
| Atrecus quadripennis | Rove Beetle |
| Attagenus pellio | Carpet Beetle |
| Attagenus schaefferi hypar | Carpet Beetle |
| Attagenus unicolor japonicus | Carpet Beetle |
| Attalus morulus | Soft-Winged Flower Beetle |
| Attalus nigrellus | Soft-Winged Flower Beetle |
| Attenella marginata | Mayfly |
| Atylus borealis | Amphipod |
| Atylus georgianus | Amphipod |
| Atylus tridens | Amphipod |
| Aufeius impressicollis | True Bug |
| Aulacorthum dorsatum | True Bug |
| Aulacorthum pterinigrum | True Bug |
| Aulacorthum solani | True Bug |
| Aulactinia incubans | Incubating Anemone |
| Auletobius congruus | Leaf And Bud Weevil |
| Auleutes epilobii | Snout Beetle |
| Auleutes nebulosus | Snout Beetle |
| Aulocara elliotti | Grasshopper |
| Aulonium longum | Cylindrical Bark Beetle |
| Auridius auratus | True Bug |
| Auridius helvus | True Bug |
| Auridius ordinatus | True Bug |
| Austroneaera semipellucida | Cuspidaria Clam |
| Austrotindaria gibbsii | Clam |
| Austrotyla borealis | Millipede |
| Autalia brevicornis | Rove Beetle |
| Autalia truncatula | Rove Beetle |
| Autographa buraetica | Cutworm Moth |
| Autographa flagellum | Silver Whip |
| Autographa rubidus | Cutworm Moth |
| Autographa sansoni | Cutworm Moth |
| Autographa speciosa | Moth |
| Autographa v-alba | Cutworm Moth |
| Autolytus cornutus | Polychaete Worm |
| Autolytus magnus | Noble Necklace-Worm |
| Autolytus prismaticus | Polychaete Worm |
| Avocettina infans | Avocet Snipe-Eel |
| Axinopalpus biplagiatus | Ground Beetle |
| Axocielita originalis | Sponge |
| Bacira verutana | Moth |
| Bactericera cockerelli | True Bug |
| Bactra furfurana | Moth |
| Bactridium ephippigerum | Root-Eating Beetle |
| Badister ferrugineus | Ground Beetle |
| Badister grandiceps | Ground Beetle |
| Badister parviceps | Ground Beetle |
| Baeocera congenera | Shining Fungus Beetle |
| Baeocera humeralis | Shining Fungus Beetle |
| Baetis bundyae | Mayfly |
| Baetis moffatti | Mayfly |
| Baetis parallelus | Mayfly |
| Baetis persecutor | Mayfly |
| Bagous nebulosus | Snout Beetle |
| Bagous restrictus | Snout Beetle |
| Bagous transversus | Snout Beetle |
| Bakerella muscotana | True Bug |
| Balanus balanus | Northern Barnacle |
| Balcanocerus provancheri | True Bug |
| Balclutha confluens | True Bug |
| Balclutha impicta | True Bug |
| Balclutha manitou | True Bug |
| Balclutha neglecta | True Bug |
| Balclutha punctata | True Bug |
| Ballana calipera | True Bug |
| Ballana chelata | True Bug |
| Ballana hebea | True Bug |
| Ballana ortha | True Bug |
| Ballana remissa | True Bug |
| Ballana titusi | True Bug |
| Balticina californica | Pennatulacean |
| Banasa calva | True Bug |
| Bandera binotella | Moth |
| Bandera virginella | Moth |
| Bankia fimbriatula | Fimbriate Shipworm |
| Barantolla americana | Polychaete Worm |
| Barbara colfaxiana | Moth |
| Barbara mappana | Moth |
| Barbourisia rufa | Velvet Whalefish |
| Barce fraterna | True Bug |
| Barentsia gracilis | Entoproct |
| Barentsia ramosa | Entoproct |
| Barentsia robusta | Entoproct |
| Baris stacesmithi | Snout Beetle |
| Barleeia haliotiphila | Abalone Barleysnail |
| Barynotus obscurus | Snout Beetle |
| Barypeithes pellucidus | Snout Beetle |
| Baryphyma trifrons | Spider |
| Baseodiscus princeps | Ribbon Worm |
| Bassaniana utahensis | Bark Crab Spider |
| Bathophilus flemingi | Highfin Dragonfish |
| Bathyagonus alascanus | Gray Starsnout |
| Bathyagonus nigripinnis | Blackfin Poacher |
| Bathyarca nucleator | Ark |
| Bathycrinus pacificus | Ten-Armed Abyssal Sea Lily |
| Bathylagus pacificus | Slender Blacksmelt |
| Bathylychnops exilis | Javelin Spookfish |
| Bathymedon nanseni | Amphipod |
| Bathyneaera tillamookensis | Cuspidaria Clam |
| Bathypathes patula | Black Coral |
| Bathyphantes alameda | Sheetweb Spider |
| Bathyphantes alascensis | Sheetweb Spider |
| Bathyphantes brevipes | Sheetweb Spider |
| Bathyphantes brevis | Sheetweb Spider |
| Bathyphantes canadensis | Sheetweb Spider |
| Bathyphantes diasosnemus | Sheetweb Spider |
| Bathyphantes eumenis | Sheetweb Spider |
| Bathyphantes keeni | Spider |
| Bathyphantes malkini | Sheetweb Spider |
| Bathyphantes orica | Sheetweb Spider |
| Bathyphantes pallidus | Sheetweb Spider |
| Bathyphantes reprobus | Sheetweb Spider |
| Bathyphantes waneta | Sheetweb Spider |
| Bathyraja abyssicola | Deepsea Skate |
| Bathysoecia bassleri | Bryozoa |
| Batrachedra praeangusta | Moth |
| Batracobdella picta | Freshwater Leech |
| Battaristis concinusella | Moth |
| Baylisascaris procyonis | Parasite |
| Beania columbiana | Bryozoa |
| Beania mirabilis | Bryozoa |
| Bedellia somnulentella | Moth |
| Beeria nematocera | Rove Beetle |
| Bellura gargantua | Moth |
| Belostoma flumineum | True Bug |
| Bembidion actuosum | Ground Beetle |
| Bembidion acutifrons | Ground Beetle |
| Bembidion aeneicolle | Ground Beetle |
| Bembidion bifossulatum | Ground Beetle |
| Bembidion bowditchii | Ground Beetle |
| Bembidion brachythorax | Ground Beetle |
| Bembidion carinula | Ground Beetle |
| Bembidion castum | Ground Beetle |
| Bembidion commotum | Ground Beetle |
| Bembidion concolor | Ground Beetle |
| Bembidion concretum | Ground Beetle |
| Bembidion convexulum | Ground Beetle |
| Bembidion diligens | Ground Beetle |
| Bembidion disjunctum | Ground Beetle |
| Bembidion dorsale | Ground Beetle |
| Bembidion dyschirinum | Ground Beetle |
| Bembidion erasum | Ground Beetle |
| Bembidion farrarae | Ground Beetle |
| Bembidion flohri | Ground Beetle |
| Bembidion fortestriatum | Ground Beetle |
| Bembidion frontale | Ground Beetle |
| Bembidion gebleri turbatum | Ground Beetle |
| Bembidion gordoni | Ground Beetle |
| Bembidion grapii | Ground Beetle |
| Bembidion gratiosum | Ground Beetle |
| Bembidion hastii | Ground Beetle |
| Bembidion hesperium | Ground Beetle |
| Bembidion inaequale opaciceps | Ground Beetle |
| Bembidion incrematum | Ground Beetle |
| Bembidion indistinctum | Ground Beetle |
| Bembidion insulatum | Ground Beetle |
| Bembidion kalumae | Ground Beetle |
| Bembidion lapponicum | Ground Beetle |
| Bembidion levettei | Ground Beetle |
| Bembidion lindrothellum | Ground Beetle |
| Bembidion lummi | Ground Beetle |
| Bembidion manningense | Ground Beetle |
| Bembidion morulum | Ground Beetle |
| Bembidion mundum | Ground Beetle |
| Bembidion mutatum | Ground Beetle |
| Bembidion nebraskense | Ground Beetle |
| Bembidion nevadense | Ground Beetle |
| Bembidion nigripes | Ground Beetle |
| Bembidion oblonguloides | Ground Beetle |
| Bembidion oblongulum | Ground Beetle |
| Bembidion obscurellum | Ground Beetle |
| Bembidion obtusangulum | Ground Beetle |
| Bembidion patruele | Ground Beetle |
| Bembidion petrosum petrosum | Ground Beetle |
| Bembidion platynoides | Ground Beetle |
| Bembidion praticola | Ground Beetle |
| Bembidion pseudocautum | Ground Beetle |
| Bembidion quadrifoveolatum | Ground Beetle |
| Bembidion quadrimaculatum dubitans | Ground Beetle |
| Bembidion recticolle | Ground Beetle |
| Bembidion rosslandicum | Ground Beetle |
| Bembidion rusticum lenensoides | Ground Beetle |
| Bembidion salinarium | Ground Beetle |
| Bembidion scopulinum | Ground Beetle |
| Bembidion sequoiae | Ground Beetle |
| Bembidion sierricola | Ground Beetle |
| Bembidion sordidum | Ground Beetle |
| Bembidion spectabile | Ground Beetle |
| Bembidion striola | Ground Beetle |
| Bembidion sulcipenne prasinoides | Ground Beetle |
| Bembidion tetracolum | Ground Beetle |
| Bembidion tigrinum | Ground Beetle |
| Bembidion timidum | Ground Beetle |
| Bembidion umbratum | Ground Beetle |
| Bembidion viator | Ground Beetle |
| Bembidion vile | Ground Beetle |
| Bembidion yukonum | Ground Beetle |
| Bembidion zephyrum | Ground Beetle |
| Bemlos concavus | Amphipod |
| Benjaminiola colorada | Cutworm Moth |
| Benthalbella dentata | Northern Pearleye |
| Benthalbella linguidens | Longfin Pearleye |
| Bentheogennema borealis | Northern Blunt-Tailed Shrimp |
| Bentheogennema burkenroadi | Burkenroad's Blunt-Tailed Shrimp |
| Bentheuphausia amblyops | Deepsea Krill |
| Benthoctopus abruptus | Octopus |
| Benthoctopus profundum | Octopus |
| Benthodesmus pacificus | North Pacific Frostfish |
| Benthodesmus tenuis | Javelinfish |
| Benthopecten claviger claviger | Sea Star |
| Benthopecten mutabilis | Sea Star |
| Berardius bairdii | Northern Pacific Bottle-Nosed Whale |
| Beringius crebicostatus | Thick-Ribbed Whelk |
| Beroe cucumis | Sea Gooseberry |
| Berosus fraternus | Water Scavenger Beetle |
| Berosus hatchi | Water Scavenger Beetle |
| Berosus striatus | Water Scavenger Beetle |
| Berryteuthis anonychus | Minimal Armhook Squid |
| Betapista dekkerae | Polychaete Worm |
| Betulaphis brevipilosa | True Bug |
| Betulaphis quadrituberculata | True Bug |
| Bicellariella brevispina | Bryozoa |
| Bicellariella ciliata | Bryozoa |
| Bicellariella stolonifera | Bryozoa |
| Bicidium aequoreae | Parasitic Anemone |
| Bicrisia edwardsiana | Bryozoa |
| Bimastos lawrenceae | Earthworm |
| Bipersona ochrocentri | True Bug |
| Bispira crassicornis | Polychaete Worm |
| Bispira pacifica | Polychaete Worm |
| Bittium challisae | Horn Snail |
| Bius estriatus | Darkling Beetle |
| Blabomma californicum | Meshweaver |
| Blapstinus discolor | Darkling Beetle |
| Blapstinus intermixtus | Darkling Beetle |
| Blapstinus metallicus | Darkling Beetle |
| Blapstinus pulverulentus | Darkling Beetle |
| Blapstinus substriatus | Darkling Beetle |
| Bledius albonotatus | Rove Beetle |
| Bledius annularis | Rove Beetle |
| Bledius aquilonarius | Rove Beetle |
| Bledius confusus | Rove Beetle |
| Bledius coulteri | Rove Beetle |
| Bledius flavipennis | Rove Beetle |
| Bledius foraminosus | Rove Beetle |
| Bledius gravidus | Rove Beetle |
| Bledius habrus | Rove Beetle |
| Bledius monstratus | Rove Beetle |
| Bledius mysticus | Rove Beetle |
| Bledius nardus | Rove Beetle |
| Bledius opacifrons | Rove Beetle |
| Bledius ruficornis | Rove Beetle |
| Bledius strenuus | Rove Beetle |
| Bledius suturalis | Rove Beetle |
| Bledius tarandus | Rove Beetle |
| Bledius turgidus | Rove Beetle |
| Bledius viriosus | Rove Beetle |
| Bledius washingtonensis | Rove Beetle |
| Bledius zophus | Rove Beetle |
| Blepharidopterus angulatus | True Bug |
| Blepharidopterus diaphanus | True Bug |
| Blepharidopterus provancheri | True Bug |
| Blethisa multipunctata aurata | Ground Beetle |
| Blethisa oregonenis | Ground Beetle |
| Blethisa quadricollis | Ground Beetle |
| Blissus occiduus | True Bug |
| Boccardia columbiana | Polychaete Worm |
| Boccardia hamata | Polychaete Worm |
| Boccardia polybranchia | Polychaete Worm |
| Boccardia proboscoidea | Polychaete Worm |
| Boccardia pugettensis | Polychaete Worm |
| Boernerina alni alaskensis | True Bug |
| Boernerina occidentalis | True Bug |
| Boernerina variabilis | True Bug |
| Bolboceras obesus | Scarab Beetle |
| Bolitobius kremeri | Rove Beetle |
| Bolitochara arcuata | Rove Beetle |
| Bolitochara carlottae | Rove Beetle |
| Bolitochara densicollis | Rove Beetle |
| Bollmaniulus hewitti | Millipede |
| Bollmaniulus spenceri | Millipede |
| Boloria bellona toddi | Meadow Fritillary |
| Boloria epithore sigridae | Western Meadow Fritillary |
| Boloria eunomia nichollae | Nichollae's Fritillary |
| Boloria natazhati | Beringian Fritillary |
| Boloria natazhati nabokovi | Beringian Fritillary |
| Boloria polaris polaris | Polar Fritillary |
| Boloriaselene | Moth |
| Bolshecapnia gregsoni | Stonefly |
| Bolshecapnia milami | Stonefly |
| Bolshecapnia rogozeri | Stonefly |
| Bolshecapnia sasquatchi | Stonefly |
| Bolshecapnia spenceri | Stonefly |
| Boltenia echinata | Solitary Ascidian |
| Bombus ashtoni | Cuckoo Bumble Bee |
| Bombus balteatus | Bumble Bee |
| Bombus fernaldae | Cuckoo Bumble Bee |
| Bombus huntii | Hunt's Bumble Bee |
| Bombus hyperboreus | Alaska Arctic Bumble Bee |
| Bombus lapponicus | Bumble Bee |
| Bombus lucorum | Buff-tailed Bumble Bee |
| Bombus morrisoni | Morrison's Bumble Bee |
| Bombus neoboreus | Bumble Bee |
| Bombus perplexus | Preplexing Bumble Bee |
| Bombus polaris | Bumble Bee |
| Bombus vandykei | Vandyke's Bumble Bee |
| Boreotrophon coronatus | Crown Trophon |
| Boreotrophon macouni | Corded Trophon |
| Boreus californicus | Snow Scorpionfly |
| Boreus elegans | Snow Scorpionfly |
| Boreus insulanus | Snow Scorpionfly |
| Boreus nix | Snow Scorpionfly |
| Boreus pilosus | Snow Scorpionfly |
| Boreus reductus | Snow Scorpionfly |
| Boschella fasciata | Checkeredbeetle |
| Bothriocephalus opsariichthydis | Parasite |
| Bothriocephalus scorpii | Parasite |
| Bothriocephalus strobilia | Parasite |
| Bothrocara molle | Soft Eelpout |
| Bothrocara pusillum | Alaska Eelpout |
| Bothropolys columbiensis | Centipede |
| Bothropolys ethus | Centipede |
| Bothropolys hoples | Centipede |
| Bothropolys victorianus | Centipede |
| Bothynotus pilosus | True Bug |
| Botocudo modestus | True Bug |
| Botruanthus benedeni | Tube Anemone |
| Bousfieldia mammalidacta | Amphipod |
| Bouvierella carcinophila | Amphipod |
| Bowerbankia gracilis aggregata | Bryozoa |
| Bowerbankia gracilis gracilis | Tubeworm Fuzz |
| Brachiacantha uteella | Lady Beetle |
| Brachinus cyanochroaticus | Ground Beetle |
| Brachinus fumans | Ground Beetle |
| Brachinus medius | Ground Beetle |
| Brachinus quadripennis | Ground Beetle |
| Brachycaudus cardui | True Bug |
| Brachycaudus rumexicolens | True Bug |
| Brachycentrus americanus | Caddisfly |
| Brachycentrus occidentialis | Caddisfly |
| Brachycoryna hardyi | Leaf Beetle |
| Brachycorynella asparagi | True Bug |
| Brachydesmus superus | Millipede |
| Brachylomia algens | Cutworm Moth |
| Brachylomia discinigra | Cutworm Moth |
| Brachylomia thula | Cutworm Moth |
| Brachymyrmex depilis | Yellow Ant |
| Brachynemurus peregrinus | Antlion |
| Brachypterus globularius | Sap-Feeding Beetle |
| Brachypterus troglodytes | Sap-Feeding Beetle |
| Brachypterus urticae | Sap-Feeding Beetle |
| Brachyramphus brevirostris | Kittlitz's Murrelet |
| Brachyramphus perdix | Long-Billed Murrelet |
| Brachyscelus crusculum | Amphipod |
| Brachysiphum thalictri | True Bug |
| Brachyusa americana | Rove Beetle |
| Brada sachalina | Polychaete Worm |
| Brada villosa | Polychaete Worm |
| Bradycellus californicus | Ground Beetle |
| Bradycellus congener | Ground Beetle |
| Bradycellus neglectus | Ground Beetle |
| Bradycellus nigrinus | Ground Beetle |
| Bradycellus nubifer | Ground Beetle |
| Bradycellus politus | Ground Beetle |
| Bradynotes obesa | Mountain Kubber Grasshopper |
| Bradynotes obesa caurus | Mountain Kubber Grasshopper |
| Branchinecta campestris | Pocket Pouch Fairy Shrimp |
| Branchiomaldane vincentii | Polychaete Worm |
| Brania brevipharyngea | Polychaete Worm |
| Brevicoryne brassicae | True Bug |
| Briarosaccus callosus | King Grab Parasitic Barnacle |
| Brochymena quadripustulata | True Bug |
| Bromius obscurus | Western Grape Rootworm |
| Brommella monticola | Meshweaver |
| Brooksetta inconspicua | True Bug |
| Brooksetta incurva | True Bug |
| Brooksetta viridicata | True Bug |
| Broscodera insignis | Ground Beetle |
| Bruceia pulverina | Powdered Lichen Moth |
| Bruchus pisorum | Pea Weevil |
| Brumoides histrio | Lady Beetle |
| Brumoides septentrionis septentrionis | Lady Beetle |
| Bruneria brunnea | Grasshopper |
| Brunsonia albertana | Millipede |
| Brunsonia atrolineata | Millipede |
| Bruzelia tuberculata | Amphipod |
| Brychius hornii | Crawling Water Beetle |
| Brychius pacificus | Crawling Water Beetle |
| Brymblia quadrimaculella | Moth |
| Bryoporus rubescens | Rove Beetle |
| Bryoporus rufescens | Rove Beetle |
| Bryoporus varians | Rove Beetle |
| Bryozoichthys marjorius | Pearly Prickleback |
| Bucculatrix ainslella | Moth |
| Bucculatrix angustisquamella | Moth |
| Bucculatrix arnicella | Moth |
| Bucculatrix canadensisella | Moth |
| Bucculatrix divisa | Moth |
| Bucculatrix eurotiella | Moth |
| Bucculatrix pomifoliella | Moth |
| Bucculatrix salutatoria | Moth |
| Bucculatrix seorsa | Moth |
| Bucculatrix tridenticola | Moth |
| Bucculatrix zophopasta | Moth |
| Buckellacris chilcotinae | Short-horned Grasshopper |
| Buckellacris chilcotinae chilcotinae | Grasshopper |
| Buckellacris hispida | Grasshopper |
| Buckellacris nuda nuda | Grasshopper |
| Buenoa macrotibialis | True Bug |
| Bugula avicularia | Bryozoa |
| Bugula cucullifera | Bryozoa |
| Bugula longirostrata | Bryozoa |
| Bugula pacifica | Bryozoa |
| Bugula pugeti | Bryozoa |
| Bulia deducta | Cutworm Moth |
| Bunodera luciopercae | Parasite |
| Buskia nitens | Bryozoa |
| Byblis longispina | Amphipod |
| Byblis veleronis | Amphipod |
| Bylgides elegans | Elegant Fifteen Scaled Worm |
| Bylgides macrolepidus | Large-Eyed Fifteen Scaled Worm |
| Bythotiara depressa | Jellyfish |
| Caballeronema wardlei | Parasite |
| Cabera borealis | Moth |
| Cabera exanthemata | Moth |
| Cabera variolaria | Moth |
| Caberea boryi | Bryozoa |
| Caberea ellisi | Bryozoa |
| Cacopsylla coryli | True Bug |
| Cacopsylla fatsiae | True Bug |
| Cacopsylla latiforceps | True Bug |
| Cacopsylla magnicauda | True Bug |
| Cacopsylla minor | True Bug |
| Cacopsylla parallela | True Bug |
| Cacopsylla peregrina | True Bug |
| Cacopsylla pyricola | True Bug |
| Cacopsylla striata | True Bug |
| Cacopsylla stricklandi | True Bug |
| Cacotherapia leucocope | Moth |
| Cadlina modesta | Modest Cadlina |
| Cadra cautella | Moth |
| Caecidotea tomalensis | Isopod |
| Caecum crebricinctum | Many-Named Caecum |
| Caenis amica | Mayfly |
| Caenis youngi | Mayfly |
| Caenoscelis ferruginea | Silken Fungus Beetle |
| Caenoscelis parallela | Silken Fungus Beetle |
| Caenurgina caerulea | Cutworm Moth |
| Caesia fossatus | Giant Western Nassa |
| Cafius canescens | Rove Beetle |
| Cafius femoralis | Rove Beetle |
| Cafius luteipennis | Rove Beetle |
| Cafius nudus johnsoni | Rove Beetle |
| Cafius seminitens | Rove Beetle |
| Caladonus coquilletti | True Bug |
| Calanana rubralineata | True Bug |
| Calaphis betulaecolens | True Bug |
| Calaphis betulicola | True Bug |
| Calaphis flava | True Bug |
| Calastacus stilirostris | Mud Shrimp |
| Calathus ruficollis grandicollis | Ground Beetle |
| Calcigorgia kinoshitae | Coral |
| Calidris subminuta | Long-Toed Stint |
| Calidris temminckii | Temminck's Stint |
| Calidris tenuirostris | Great Knot |
| Calineuria californica | Stonefly |
| Caliroa cerasi | Pear Sawfly |
| Calitys minor | Bark-Gnawing Beetle |
| Calleida viridis amoena | Ground Beetle |
| Callianax pycna | Zigzag Olive |
| Callicorixa alaskensis | True Bug |
| Callicorixa audeni | True Bug |
| Callicorixa scudderi | True Bug |
| Callicorixa vulnerata | True Bug |
| Calligrapha californica californica | Leaf Beetle |
| Calligrapha philadelphica | Leaf Beetle |
| Calligrapha sigmoidea | Leaf Beetle |
| Calligrapha verrucosa | Leaf Beetle |
| Callilepis eremella | Ground Spider |
| Callilepis pluto | Ground Spider |
| Calliopius behringi | Amphipod |
| Calliopius carinatus | Amphipod |
| Calliopius columbianus | Amphipod |
| Calliopius pacificus | Amphipod |
| Calliostoma bernardi | Bernard's Shiny White Top Shell |
| Callipterinella calliptera | True Bug |
| Callipterinella minutissima | True Bug |
| Callisto denticulella | Moth |
| Callithaca tenerrima | Thin-Shell Littleneck Clam |
| Callobius canada | Hackledmesh Weaver |
| Callobius enus | Hackledmesh Weaver |
| Callobius nomeus | Hackledmesh Weaver |
| Callophrys iroides iroides | Western Elfin |
| Callophrys mossii schryveri | Moss' Elfin |
| Callophrys nelsoni rosneri | Cedar Hairstreak |
| Callophrys niphon | Eastern Pine Elfin |
| Callophrys niphon clarki | Eastern Pine Elfin |
| Callopora armata | Bryozoa |
| Callopora exilis | Bryozoa |
| Callopora horrida | Bryozoa |
| Callopora inconspicua | Bryozoa |
| Callopora lineata | Bryozoa |
| Calocarides quinqueseriatus | Keeled Mud Lobster |
| Calocarides spinulicauda | Shrimp |
| Calochromus dimidiatus | Net-Winged Beetle |
| Calochromus fervens | Net-Winged Beetle |
| Calophasia lunula | Cutworm Moth |
| Caloptilia alnicolella | Moth |
| Caloptilia alnivorella | Moth |
| Caloptilia invariabilis | Moth |
| Caloptilia melanocarpae | Moth |
| Caloptilia pulchella | Moth |
| Caloptilia rhoifoliella | Moth |
| Caloptilia sanguinella | Moth |
| Caloptilia serotinella | Moth |
| Caloptilia strictella | Moth |
| Calosoma calidum | Fiery Hunter |
| Calosoma cancellatum | Ground Beetle |
| Calosoma frigidum | Ground Beetle |
| Calosoma luxatum | Ground Beetle |
| Calosoma moniliatum | Ground Beetle |
| Calosoma tepidum | Ground Beetle |
| Calosoma wilkesii | Ground Beetle |
| Calvia quatuordecimguttata | Lady Beetle |
| Calycopsis bigelowi | Jellyfish |
| Calycopsis nematophora | Jellyfish |
| Calymmaria emertoni | Hahniid Spider |
| Calymmaria monicae | Hahniid Spider |
| Calymmaria nana | Hahniid Spider |
| Calymmaria suprema | Hahniid Spider |
| Calyptomerus oblongulus | Minute Beetle |
| Calyptraea fastigiata | Cup-And-Saucer Snail |
| Cameraria gaultheriella | Moth |
| Camponotus laevigatus | Carpenter Ant |
| Camponotus nearcticus | Carpenter Ant |
| Camponotus vicinus | Carpenter Ant |
| Campylomma verbasci | True Bug |
| Campyloneura virgula | True Bug |
| Canalidion montanum | Spider |
| Candocyprinotus ovatus | Seed Shrimp |
| Candona albicans | Seed Shrimp |
| Candona caudata | Seed Shrimp |
| Candona compressa | Seed Shrimp |
| Candona distincta | Seed Shrimp |
| Candona paraohioensis | Seed Shrimp |
| Candona renoensis | Seed Shrimp |
| Candona stagnalis | Seed Shrimp |
| Candona subacuminata | Seed Shrimp |
| Canifa pallipes | False Flower Beetle |
| Cantharis alticola | Soldier Beetle |
| Cantharis aneba borealis | Soldier Beetle |
| Cantharis beta | Soldier Beetle |
| Cantharis consors | Soldier Beetle |
| Cantharis curtisi | Soldier Beetle |
| Cantharis oregona | Soldier Beetle |
| Cantharis transmarina scopa | Soldier Beetle |
| Cantharis transmarina transmarina | Soldier Beetle |
| Canthon praticola | Scarab Beetle |
| Canthon simplex | Scarab Beetle |
| Capheira mollis | Sea Cucumber |
| Capheira sulcata | Sea Cucumber |
| Capillaria exilis | Parasite |
| Capillaria freemani | Parasite |
| Capillaria lycodi | Parasite |
| Capillaria obsignata | Parasite |
| Capillaria parophrysi | Parasite |
| Capitella capitata | Polychaete Worm |
| Capitophorus carduinus | True Bug |
| Capitophorus hippophaes | True Bug |
| Capitophorus horni | True Bug |
| Capnia cheama | Stonefly |
| Capnia coloradensis | Stonefly |
| Capnia confusa | Stonefly |
| Capnia elongata | Stonefly |
| Capnia excavata | Stonefly |
| Capnia gracilaria | Stonefly |
| Capnia melia | Stonefly |
| Capnia nana | Stonefly |
| Capnia nearctica | Stonefly |
| Capnia petila | Stonefly |
| Capnia pileata | Stonefly |
| Capnia sextuberculata | Stonefly |
| Capnia vernalis | Stonefly |
| Capperia evansi | Moth |
| Caprella angusta | Amphipod |
| Caprella borealis | Amphipod |
| Caprella californica | Amphipod |
| Caprella ciliata | Amphipod |
| Caprella drepanocheir | Amphipod |
| Caprella equilibra | Amphipod |
| Caprella gracilior | Amphipod |
| Caprella incisa | Amphipod |
| Caprella irregularis | Amphipod |
| Caprella laeviscula | Amphipod |
| Caprella mendax | Amphipod |
| Caprella natalensis | Amphipod |
| Caprella pilidigitata | Amphipod |
| Caprella pustualta | Amphipod |
| Caprella radiuscula | Amphipod |
| Caprella striata | Amphipod |
| Caprella ungulina | Amphipod |
| Caprella verrucosa | Amphipod |
| Caprimulgus arizonae | Mexican Whip-Poor-Will |
| Capsus ater | True Bug |
| Capsus cinctus | True Bug |
| Carabus maeander maeander | Ground Beetle |
| Carabus serratus | Ground Beetle |
| Carabus taedatus agassii | Ground Beetle |
| Caradrina camina | Moth |
| Carcharodon carcharias | White Shark |
| Carcinonemertes epialti | Ribbon Worm |
| Carcinonemertes errans | Ribbon Worm |
| Carcinops pumilio | Clown Beetle |
| Cardiastethus borealis | True Bug |
| Cardiophorus alpestris | Click Beetle |
| Cardiophorus brunnipennis | Click Beetle |
| Cardiophorus communius | Click Beetle |
| Cardiophorus kooskooskiensis | Click Beetle |
| Cardiophorus latiusculus | Click Beetle |
| Cardiophorus nevadensis | Click Beetle |
| Cardiophorus plebejus | Click Beetle |
| Cardiophorus plexus | Click Beetle |
| Cardiophorus propinquus | Click Beetle |
| Cardiophorus pubescens | Click Beetle |
| Cardiophorus tenebrosus | Click Beetle |
| Cardiophorus tumidicollis | Click Beetle |
| Cardiophorus tutus | Click Beetle |
| Careproctus colletti | Alaska Snailfish |
| Careproctus cypselurus | Falcate Snailfish |
| Careproctus furcellus | Snailfish |
| Careproctus gilberti | Smalldisk Snailfish |
| Careproctus oregonensis | Smallfin Snailfish |
| Careproctus ovigerum | Abyssal Snailfish |
| Carineogammarus makarovi | Amphipod |
| Carolinaia schlingeri | True Bug |
| Carpelimus bilineatus | Rove Beetle |
| Carpelimus congener | Rove Beetle |
| Carpelimus conjunctus | Rove Beetle |
| Carpelimus diffusus | Rove Beetle |
| Carpelimus harneyi | Rove Beetle |
| Carpelimus nanuloides | Rove Beetle |
| Carpelimus vancouverensis | Rove Beetle |
| Carpelimus volans | Rove Beetle |
| Carphacis nepigonensis | Rove Beetle |
| Carphoborus intermedius | Bark And Ambrosia Beetle |
| Carphoborus ponderosae | Bark And Ambrosia Beetle |
| Carphoborus vandykei | Bark And Ambrosia Beetle |
| Carpophilus discoideus | Sap-Feeding Beetle |
| Carpophilus hemipterus | Driedfruit Beetle |
| Carpophilus mutilatus | Sap-Feeding Beetle |
| Carrhydrus crassipes | Predacious Diving Beetle |
| Carsia sororiata | Moth |
| Carsonus aridus | True Bug |
| Carterocephalus palaemon magnus | Arctic Skipper |
| Carterocephalus palaemon skada | Arctic Skipper |
| Cartodere constricta | Plaster Beetle |
| Carulaspis juniperi | True Bug |
| Caryocolum pullatella | Moth |
| Caryophyllia arnoldi | Stony Coral |
| Cascadoperla trictura | Stonefly |
| Cassida flaveola | Leaf Beetle |
| Castianeira alteranda | Sun Spider |
| Castianeira longipalpa | Sun Spider |
| Catabena lineolata | Cutworm Moth |
| Catablema nodulosa | Jellyfish |
| Catharus fuscescens | Veery |
| Catocala allusa | Moth |
| Catocala briseis | Moth |
| Catocala californica | Moth |
| Catocala faustina | Moth |
| Catocala junctura | Moth |
| Catocala ultronia | Moth |
| Catocala unijuga | Once-married Underwing Moth |
| Catopocerus cryptophagoides | Round Fungus Beetle |
| Catops alpinus sitkanus | Round Fungus Beetle |
| Catops alsiosus | Round Fungus Beetle |
| Catops americanus | Round Fungus Beetle |
| Catops basilaris | Round Fungus Beetle |
| Catops egenus | Round Fungus Beetle |
| Catops gratiosus | Round Fungus Beetle |
| Catops luridipennis | Round Fungus Beetle |
| Catops mathersi | Round Fungus Beetle |
| Catops simplex | Round Fungus Beetle |
| Catoptria maculalis | Moth |
| Catoptria trichostomus | Moth |
| Catoptrichus frankenhaeuseri | Round Fungus Beetle |
| Catostomus columbianus | Bridgelip Sucker |
| Catostomus commersonii | White Sucker |
| Catostomus platyrhynchus | Mountain Sucker |
| Catriona columbiana | British Columbia Aeolid |
| Cauchas cockerelli | Moth |
| Cauchas simpliciella | Moth |
| Caudatella heterocaudata | Mayfly |
| Caudatella jacobi | Mayfly |
| Caulibugula ciliata | Bryozoa |
| Caulibugula occidentalis | Bryozoa |
| Caulleriella hamata | Polychaete Worm |
| Caulolatilus princeps | Ocean Whitefish |
| Cauloramphus echinus | Bryozoa |
| Cauloramphus spiniferum | Bryozoa |
| Cavariella aegopodii | True Bug |
| Cavariella archangelicae | True Bug |
| Cavariella borealis | True Bug |
| Cavariella digitata | True Bug |
| Cavariella konoi | True Bug |
| Cavariella pastinacae | True Bug |
| Cavariella theobaldi | True Bug |
| Ccydia miscitata | Moth |
| Cedoaphis incognita | True Bug |
| Cellaria mandibulata | Bryozoa |
| Celleporella hyalina | Glassy-White Encrusting Bryozoan |
| Cenocorixa andersoni | Anderson's Water Boatman |
| Cenocorixa bifida hungerfordi | True Bug |
| Cenocorixa blaisdelli | True Bug |
| Cenocorixa dakotensis | True Bug |
| Cenocorixa expleta | True Bug |
| Cenocorixa utahensis | True Bug |
| Centromerita bicolor | Sheetweb Spider |
| Centromerus longibulbus | Sheetweb Spider |
| Centromerus sylvaticus | Spider |
| Centropt |