Find out what mammals, insects, fish, plants, etc. are endangered here. Use the selection box below to view full lists by group.
The following is a list of all endangered crustaceans.
| | Species Name | Scientific Name | Range |
|---|
| 1. | Acanthocyclops hypogeus | Acanthocyclops hypogeus | Slovenia |
| 2. | Adeleana forcarti | Adeleana forcarti | Indonesia |
| 3. | Aglaodiaptomus kingsburyae | Aglaodiaptomus kingsburyae | United States |
| 4. | Aglaodiaptomus marshianus | Aglaodiaptomus marshianus | United States |
| 5. | Alabama Cave Shrimp | Palaemonias alabamae | Alabama |
| 6. | Alabama Well Amphipod | Stygobromus smithii | Alabama |
| 7. | Allacanthos pittieri | Allacanthos pittieri | Costa Rica, Panama |
| 8. | Allodiaptomus satanas | Allodiaptomus satanas | India |
| 9. | Alona hercegovinae | Alona hercegovinae | Bosnia and Herzegovina |
| 10. | Alona sketi | Alona sketi | Slovenia |
| 11. | Alona smirnovi | Alona smirnovi | Republic of Macedonia |
| 12. | Angular Dwarf Crayfish | Cambarellus lesliei | Alabama, Mississippi |
| 13. | Antrisocopia prehensilis | Antrisocopia prehensilis | Bermuda - North Atlantic Ocean |
| 14. | Apalachicola Cave Crayfish | Cambarus cryptodytes | Florida, Georgia |
| 15. | Aquadulcaris pheronyx | Aquadulcaris pheronyx | South Africa |
| 16. | Arachnothelphusa melanippe | Arachnothelphusa melanippe | Indonesia, Malaysia |
| 17. | Arctodiaptomus burduricus | Arctodiaptomus burduricus | Turkey |
| 18. | Arctodiaptomus euacanthus | Arctodiaptomus euacanthus | India |
| 19. | Arctodiaptomus kamtschaticus | Arctodiaptomus kamtschaticus | Russia |
| 20. | Arctodiaptomus michaeli | Arctodiaptomus michaeli | India |
| 21. | Arizona Cave Amphipod | Stygobromus arizonensis | Arizona |
| 22. | Arubolana imula | Arubolana imula | Aruba Island (Netherland Antilles) |
| 23. | Astacoides crosnieri | Astacoides crosnieri | Madagascar |
| 24. | Astacoides petiti | Astacoides petiti | Madagascar |
| 25. | Atlantasellus cavernicolus | Atlantasellus cavernicolus | Bermuda - North Atlantic Ocean |
| 26. | Atyid Shrimp | Typhlatya iliffei | Bermuda - North Atlantic Ocean |
| 27. | Austrothelphusa tigrina | Austrothelphusa tigrina | Australia |
| 28. | Austrothelphusa valentula | Austrothelphusa valentula | Australia |
| 29. | Austrothelphusa wasselli | Austrothelphusa wasselli | Australia |
| 30. | Avotrichodactylus oaxensis | Avotrichodactylus oaxensis | Mexico |
| 31. | Balcones Cave Amphipod | Stygobromus balconis | Texas |
| 32. | Balcones Cave Shrimp | Palaemonetes antrorum | Texas |
| 33. | Barr's Cave Amphipod | Stygobromus barri | Missouri |
| 34. | Bastrop Crayfish | Procambarus texanus | Texas |
| 35. | Bat Cave Isopod | Caecidotea macropoda | Arkansas, Oklahoma |
| 36. | Bath County Cave Amphipod | Stygobromus mundus | Virginia |
| 37. | Bearded Red Crayfish | Procambarus pogum | Mississippi |
| 38. | Beautiful Crayfish | Cambarus speciosus | Georgia |
| 39. | Benton County Cave Crayfish | Cambarus aculabrum | Arkansas |
| 40. | Bermuda Cave Amphipod | Pseudoniphargus grandimanus | Bermuda - North Atlantic Ocean |
| 41. | Bifurcated Cave Amphipod | Stygobromus bifurcatus | Texas |
| 42. | Big Blue Spring Cave Crayfish | Procambarus horsti | Florida |
| 43. | Big Sandy Crayfish | Cambarus veteranus | Kentucky, Virginia, West Virginia |
| 44. | Big South Fork Crayfish | Cambarus bouchardi | Kentucky, Tennessee |
| 45. | Big-cheeked Cave Crayfish | Procambarus delicatus | Florida |
| 46. | Black Creek Crayfish | Procambarus pictus | Florida |
| 47. | Blackbarred Crayfish | Cambarus unestami | Alabama, Georgia |
| 48. | Blackbelted Crayfish | Procambarus nigrocinctus | Texas |
| 49. | Bluegrass Crayfish | Cambarus batchi | Kentucky |
| 50. | Boeckella bispinosa | Boeckella bispinosa | Australia |
| 51. | Boeckella calcaris | Boeckella calcaris | Bolivia, Peru |
| 52. | Boeckella geniculata | Boeckella geniculata | Australia |
| 53. | Boeckella nyoraensis | Boeckella nyoraensis | Australia |
| 54. | Boeckella shieli | Boeckella shieli | Australia |
| 55. | Bogidiella bermudensis | Bogidiella bermudensis | Bermuda - North Atlantic Ocean |
| 56. | Boreas uglowi | Boreas uglowi | Madagascar |
| 57. | Bottiella cucutensis | Bottiella cucutensis | Colombia, Venezuela |
| 58. | Bottiella medemi | Bottiella medemi | Colombia, Venezuela |
| 59. | Bousfield's Amphipod | Gammarus bousfieldi | Illinois, Indiana, Kentucky |
| 60. | Bowman's Cave Amphipod | Stygobromus bowmani | Oklahoma |
| 61. | Branchinecta belki | Branchinecta belki | Mexico |
| 62. | Branchinecta mexicana | Branchinecta mexicana | Mexico |
| 63. | Branchinella lithaca | Branchinella lithaca | United States |
| 64. | Branchinella alachua | Branchinella alachua | United States |
| 65. | Branchinella apophysata | Branchinella apophysata | Australia |
| 66. | Branchinella basispina | Branchinella basispina | Australia |
| 67. | Branchinella denticulata | Branchinella denticulata | Australia |
| 68. | Branchinella simplex | Branchinella simplex | Australia |
| 69. | Branchinella wellardi | Branchinella wellardi | Australia |
| 70. | Brawleys Fork Crayfish | Cambarus williami | Tennessee |
| 71. | Brazoria Crayfish | Procambarus brazoriensis | Texas |
| 72. | Brine Shrimp | Parartemia contracta | Australia |
| 73. | Broad River Spiny Crayfish | Cambarus spicatus | North Carolina, South Carolina |
| 74. | Broad-fingered Crayfish | Astacus astacus | Asia, Europe |
| 75. | Burnsville Cove Cave Amphipod | Stygobromus conradi | Virginia |
| 76. | Burrowing Bog Crayfish | Fallicambarus burrisi | Alabama, Mississippi |
| 77. | Burrowing Crayfish | Engaeus australis | Australia |
| 78. | Burrowing Crayfish | Engaeus curvisuturus | Australia |
| 79. | Burrowing Crayfish | Engaeus disjuncticus | Australia |
| 80. | Burrowing Crayfish | Engaeus granulatus | Australia |
| 81. | Burrowing Crayfish | Engaeus mallacoota | Australia |
| 82. | Burrowing Crayfish | Engaeus martigener | Australia |
| 83. | Burrowing Crayfish | Engaeus nulloporius | Australia |
| 84. | Burrowing Crayfish | Engaeus orramakunna | Australia |
| 85. | Burrowing Crayfish | Engaeus rostrogaleatus | Australia |
| 86. | Burrowing Crayfish | Engaeus spinicaudatus | Australia |
| 87. | Burrowing Crayfish | Engaeus sternalis | Australia |
| 88. | Burrowing Crayfish | Engaeus urostrictus | Australia |
| 89. | Burrowing Crayfish | Engaeus phyllocercus | Australia |
| 90. | Calamoecia australica | Calamoecia australica | Australia |
| 91. | Calamoecia elongata | Calamoecia elongata | Australia |
| 92. | Calamoecia zeidleri | Calamoecia zeidleri | Australia |
| 93. | Calconiscellus gotscheensis | Calconiscellus gotscheensis | Slovenia |
| 94. | California Bay Pea Crab | Parapinnixa affinis | California |
| 95. | California Freshwater Shrimp | Syncaris pacifica | California |
| 96. | Cambarus cymatilis | Cambarus cymatilis | Georgia, Tennessee |
| 97. | Cambarus elkensis | Cambarus elkensis | West Virginia |
| 98. | Cambarus strigosus | Cambarus strigosus | Georgia |
| 99. | Cambarus subterraneus | Cambarus subterraneus | Oklahoma |
| 100. | Camp Shelby Burrowing Crayfish | Fallicambarus gordoni | Mississippi |
| 101. | Canthocamptus dedeckkeri | Canthocamptus dedeckkeri | Australia |
| 102. | Canthocamptus echinopyge | Canthocamptus echinopyge | Australia |
| 103. | Canthocamptus longipes | Canthocamptus longipes | Australia |
| 104. | Canthocamptus mammillifurca | Canthocamptus mammillifurca | Australia |
| 105. | Canthocamptus sublaevis | Canthocamptus sublaevis | Australia |
| 106. | Canthocamptus tasmaniae | Canthocamptus tasmaniae | Australia |
| 107. | Carinurella paradoxa | Carinurella paradoxa | Italy, Slovenia |
| 108. | Cascade Cave Amphipod | Stygobromus dejectus | Texas |
| 109. | Central Missouri Cave Amphipod | Allocrangonyx hubrichti | Arkansas, Missouri |
| 110. | Ceuthonectes rouchi | Ceuthonectes rouchi | Slovenia |
| 111. | Ceylonthelphusa alpina | Ceylonthelphusa alpina | Sri Lanka |
| 112. | Ceylonthelphusa armata | Ceylonthelphusa armata | Sri Lanka |
| 113. | Ceylonthelphusa callista | Ceylonthelphusa callista | Sri Lanka |
| 114. | Ceylonthelphusa cavatrix | Ceylonthelphusa cavatrix | Sri Lanka |
| 115. | Ceylonthelphusa diva | Ceylonthelphusa diva | Sri Lanka |
| 116. | Ceylonthelphusa durrelli | Ceylonthelphusa durrelli | Sri Lanka |
| 117. | Ceylonthelphusa kotagama | Ceylonthelphusa kotagama | Sri Lanka |
| 118. | Ceylonthelphusa nana | Ceylonthelphusa nana | Sri Lanka |
| 119. | Ceylonthelphusa nata | Ceylonthelphusa nata | Sri Lanka |
| 120. | Ceylonthelphusa orthos | Ceylonthelphusa orthos | Sri Lanka |
| 121. | Ceylonthelphusa sanguinea | Ceylonthelphusa sanguinea | Sri Lanka |
| 122. | Ceylonthelphusa savitriae | Ceylonthelphusa savitriae | Sri Lanka |
| 123. | Ceylonthelphusa kandambyi | Ceylonthelphusa kandambyi | Sri Lanka |
| 124. | Ceylonthelphusa venusta | Ceylonthelphusa venusta | Sri Lanka |
| 125. | Chaceus ibiricensis | Chaceus ibiricensis | Colombia |
| 126. | Chatooga Crayfish | Cambarus scotti | Alabama, Georgia |
| 127. | Chattahoochee Crayfish | Cambarus howardi | Alabama, Georgia, North Carolina |
| 128. | Chickamanga Crayfish | Cambarus extraneus | Georgia, Tennessee |
| 129. | Chirocephalus croaticus | Chirocephalus croaticus | Croatia, Slovenia |
| 130. | Chirocephalus pelagonicus | Chirocephalus pelagonicus | Republic of Macedonia |
| 131. | Chirocephalus reiseri | Chirocephalus reiseri | Bosnia and Herzegovina |
| 132. | Choctaw Riverlet Crayfish | Hobbseus valleculus | Mississippi |
| 133. | Cirolanid Isopod | Arubolana aruboides | Bermuda - North Atlantic Ocean |
| 134. | Clanton's Cave Amphipod | Stygobromus clantoni | Kansas, Missouri |
| 135. | Clifton Cave Isopod | Caecidotea barri | Kentucky |
| 136. | Clinothelphusa kakoota | Clinothelphusa kakoota | Sri Lanka |
| 137. | Coahuila Isopod | Mexistenasellus coahuila | Mexico, Texas |
| 138. | Coastal Flatwoods Crayfish | Procambarus apalachicolae | Florida |
| 139. | Coastal Lowland Cave Crayfish | Procambarus leitheuseri | Florida |
| 140. | Coccusa cristicervix | Coccusa cristicervix | Malaysia (Sarawak) |
| 141. | Cocoharpinia iliffei | Cocoharpinia iliffei | Bermuda - North Atlantic Ocean |
| 142. | Common Yabby | Cherax destructor | Australia |
| 143. | Conservancy Fairy Shrimp | Branchinecta conservatio | California |
| 144. | Cooper's Cave Amphipod | Stygobromus cooperi | West Virginia |
| 145. | Coosawattae Crayfish | Cambarus coosawattae | Georgia |
| 146. | Corrollton Crayfish | Procambarus connus | Mississippi |
| 147. | Cryptopotamon anacoluthon | Cryptopotamon anacoluthon | Hong Kong |
| 148. | Cuban Cave Shrimp | Barbouria cubensis | Bermuda - North Atlantic Ocean |
| 149. | Curassanthura bermudensis | Curassanthura bermudensis | Bermuda - North Atlantic Ocean |
| 150. | Cypress Crayfish | Cambarellus blacki | Florida |
| 151. | Deckenia imitatrix | Deckenia imitatrix | Kenya, Somalia, Tanzania |
| 152. | Deckenia mitis | Deckenia mitis | Kenya, Tanzania |
| 153. | Devil's Sinkhole Amphipod | Stygobromus hadenoecus | Texas |
| 154. | Diminutive Amphipod | Gammarus hyalelloides | Texas |
| 155. | Distocambarus devexus | Distocambarus devexus | Georgia |
| 156. | Distocambarus youngineri | Distocambarus youngineri | South Carolina |
| 157. | Doimon doichiangdao | Doimon doichiangdao | Thailand |
| 158. | Doimon doisutep | Doimon doisutep | Thailand |
| 159. | Dussartius baeticus | Dussartius baeticus | Portugal, Spain |
| 160. | Dwarf River Crab | Liberonautes nanoides | Liberia |
| 161. | Edisto Crayfish | Procambarus echinatus | South Carolina |
| 162. | Elaphoidella amabilis | Elaphoidella amabilis | United States |
| 163. | Elaphoidella franci | Elaphoidella franci | Slovenia |
| 164. | Elaphoidella jeanneli | Elaphoidella jeanneli | Slovenia |
| 165. | Elaphoidella kieferi | Elaphoidella kieferi | Slovenia |
| 166. | Elevated Spring Amphipod | Stygobromus elatus | Arkansas |
| 167. | Elsalvadoria zurstrasseni | Elsalvadoria zurstrasseni | El Salvador |
| 168. | Engaewa similis | Engaewa similis | Australia |
| 169. | Eodiaptomus lumholtzi | Eodiaptomus lumholtzi | Australia |
| 170. | Eodiaptomus shihi | Eodiaptomus shihi | India |
| 171. | Eoleptestheria spinosa | Eoleptestheria spinosa | Croatia, Serbia and Montenegro |
| 172. | Ephemeral Cave Amphipod | Stygobromus ephemerus | Virginia |
| 173. | Epilobocera haytensis | Epilobocera haytensis | Dominican Republic, Haiti |
| 174. | Epilobocera wetherbeei | Epilobocera wetherbeei | Dominican Republic |
| 175. | Epischura baikalensis | Epischura baikalensis | Russia |
| 176. | Erebonectes nesioticus | Erebonectes nesioticus | Bermuda - North Atlantic Ocean |
| 177. | Escambia Crayfish | Procambarus escambiensis | Alabama, Florida |
| 178. | Etowah Crayfish | Cambarus fasciatus | Georgia |
| 179. | Eucrenonaspides oinotheke | Eucrenonaspides oinotheke | Australia (Tasmania) |
| 180. | Ezell's Cave Amphipod | Stygobromus flagellatus | Texas |
| 181. | Fabaeformiscandona aemonae | Fabaeformiscandona aemonae | Slovenia |
| 182. | Fallicambarus gilpini | Fallicambarus gilpini | Arkansas |
| 183. | Fibulacamptus bisetosus | Fibulacamptus bisetosus | Australia |
| 184. | Fibulacamptus gracilior | Fibulacamptus gracilior | Australia |
| 185. | Florida Cave Amphipod | Crangonyx grandimanus | Florida |
| 186. | Florida Cave Shrimp | Palaemonetes cummingi | Florida |
| 187. | Florida Fairy Shrimp | Dexteria floridana | Florida |
| 188. | Fredius granulatus | Fredius granulatus | Colombia |
| 189. | French Broad Crayfish | Cambarus reburrus | North Carolina |
| 190. | Geithusa pulchra | Geithusa pulchra | Malaysia |
| 191. | Geothelphusa levicervix | Geothelphusa levicervix | Japan |
| 192. | Geothelphusa miyakoensis | Geothelphusa miyakoensis | Japan |
| 193. | Giant Freshwater Crayfish | Astacopsis gouldi | Australia |
| 194. | Grady's Cave Amphipod | Stygobromus gradyi | California |
| 195. | Grandbassa River Crab | Liberonautes grandbassa | Liberia |
| 196. | Green Crab | Geothelphusa lutao | China, Taiwan |
| 197. | Greenbrier Cave Amphipod | Stygobromus emarginatus | Maryland, West Virginia |
| 198. | Greenbrier Cave Crayfish | Cambarus nerterius | West Virginia |
| 199. | Greensboro Burrowing Crayfish | Cambarus catagius | North Carolina |
| 200. | Hainanpotamon orientale | Hainanpotamon orientale | China (Hainan) |
| 201. | Haplophthalmus abbreviatus | Haplophthalmus abbreviatus | Slovenia |
| 202. | Haplophthalmus rhinoceros | Haplophthalmus rhinoceros | Croatia, Slovenia |
| 203. | Hara's Cave Amphipod | Stygobromus harai | California |
| 204. | Hatchie Burrowing Crayfish | Fallicambarus hortoni | Tennessee |
| 205. | Hay's Spring Amphipod | Stygobromus hayi | District of Columbia |
| 206. | Heliodiaptomus kolleruensis | Heliodiaptomus kolleruensis | India |
| 207. | Heliodiaptomus pulcher | Heliodiaptomus pulcher | India |
| 208. | Hell Creek Crayfish | Cambarus zophonastes | Arkansas |
| 209. | Hemiboeckella powellensis | Hemiboeckella powellensis | Australia |
| 210. | Hesperodiaptomus augustaensis | Hesperodiaptomus augustaensis | North Carolina |
| 211. | Hesperodiaptomus californiensis | Hesperodiaptomus californiensis | California |
| 212. | Heterothelphusa fatum | Heterothelphusa fatum | Malaysia, Thailand |
| 213. | Hickman's Pygmy Mountain Shrimp | Allanaspides hickmani | Australia (Tasmania) |
| 214. | Hiwassee Crayfish | Cambarus hiwasseensis | Georgia, North Carolina, Tennessee |
| 215. | Hiwassee Headwater Crayfish | Cambarus parrishi | Georgia, North Carolina |
| 216. | Hobb's Cave Amphipod | Crangonyx hobbsi | Florida |
| 217. | Hobbseus cristatus | Hobbseus cristatus | Mississippi |
| 218. | Hypolobocera exuca | Hypolobocera exuca | Colombia, Ecuador |
| 219. | Hypolobocera alata | Hypolobocera alata | Colombia |
| 220. | Hypolobocera andagoensis | Hypolobocera andagoensis | Colombia |
| 221. | Hypolobocera barbacensis | Hypolobocera barbacensis | Colombia |
| 222. | Hypolobocera cajambrensis | Hypolobocera cajambrensis | Colombia |
| 223. | Hypolobocera gracilignatha | Hypolobocera gracilignatha | Ecuador, Peru |
| 224. | Hypolobocera rathbuni | Hypolobocera rathbuni | Ecuador |
| 225. | Hypolobocera rotundilobata | Hypolobocera rotundilobata | Colombia |
| 226. | Hypolobocera velezi | Hypolobocera velezi | Colombia |
| 227. | Ibanum pilimanus | Ibanum pilimanus | Malaysia |
| 228. | Idunella sketi | Idunella sketi | Bermuda - North Atlantic Ocean |
| 229. | Illinois Cave Amphipod | Gammarus acherondytes | Illinois |
| 230. | Imnadia banatica | Imnadia banatica | Serbia and Montenegro |
| 231. | Imnadia cristata | Imnadia cristata | Serbia and Montenegro |
| 232. | Imnadia panonica | Imnadia panonica | Serbia and Montenegro |
| 233. | Indochinamon bhumibol | Indochinamon bhumibol | Thailand |
| 234. | Indochinamon villosum | Indochinamon villosum | Laos |
| 235. | Indochinamon cua | Indochinamon cua | Vietnam |
| 236. | Indochinamon guttum | Indochinamon guttum | Laos |
| 237. | Indochinamon mieni | Indochinamon mieni | Vietnam |
| 238. | Ingolfiella longipes | Ingolfiella longipes | Bermuda - North Atlantic Ocean |
| 239. | Iomon nan | Iomon nan | Thailand |
| 240. | Iomon luangprabangensis | Iomon luangprabangensis | Laos |
| 241. | Irmengardia didacta | Irmengardia didacta | Malaysia |
| 242. | Irmengardia nemestrinus | Irmengardia nemestrinus | Indonesia |
| 243. | Irmengardia johnsoni | Irmengardia johnsoni | Singapore |
| 244. | Isolapotamon bauense | Isolapotamon bauense | Malaysia |
| 245. | Jackson Prarie Crayfish | Procambarus barbiger | Mississippi |
| 246. | Johora punicea | Johora punicea | Malaysia |
| 247. | Johora singaporensis | Johora singaporensis | Singapore |
| 248. | Johora counsilmani | Johora counsilmani | Malaysia |
| 249. | Johora gapensis | Johora gapensis | Malaysia |
| 250. | Johora johorensis | Johora johorensis | Malaysia |
| 251. | Johora thoi | Johora thoi | Malaysia |
| 252. | Johora tiomanensis | Johora tiomanensis | Malaysia |
| 253. | Kapcypriodopsis barnardi | Kapcypriodopsis barnardi | South Africa (Western Cape Province) |
| 254. | Kauai Cave Amphipod | Spelaeorchestia koloana | Hawaii |
| 255. | Kentucky Cave Shrimp | Palaemonias ganteri | Kentucky |
| 256. | Lagniappe Crayfish | Procambarus lagniappe | Alabama, Mississippi |
| 257. | Least Crayfish | Cambarellus diminutus | Alabama, Mississippi |
| 258. | Lee County Cave Isopod | Lirceus usdagalun | Virginia |
| 259. | Lepidothelphusa cognetti | Lepidothelphusa cognetti | Malaysia (Sarawak) |
| 260. | Leptocaris stromatolicolus | Leptocaris stromatolicolus | Mexico |
| 261. | Leucocythere helenae | Leucocythere helenae | South Africa |
| 262. | Lindacatalina sumacensis | Lindacatalina sumacensis | Colombia, Ecuador |
| 263. | Liotelphusa gagei | Liotelphusa gagei | Bhutan, India |
| 264. | Liotelphusa laevis | Liotelphusa laevis | Bhutan, India |
| 265. | Liotelphusa quadrata | Liotelphusa quadrata | India |
| 266. | Little Tennessee Crayfish | Cambarus georgiae | Georgia, North Carolina |
| 267. | Lobster Claw Crab | Liberonautes rubigimanus | Guinea, Liberia |
| 268. | Long-legged Cave Amphipod | Stygobromus longipes | Texas |
| 269. | Longhorn Fairy Shrimp | Branchinecta longiantenna | California |
| 270. | Lonoke Crayfish | Procambarus ferrugineus | Arkansas |
| 271. | Louisea balssi | Louisea balssi | Cameroon |
| 272. | Louisea edeaensis | Louisea edeaensis | Cameroon |
| 273. | Lovenula excellens | Lovenula excellens | South Africa |
| 274. | Lovenula simplex | Lovenula simplex | South Africa |
| 275. | Lugbe River Crab | Liberonautes lugbe | Liberia |
| 276. | Mackenzie's Cave Amphipod | Stygobromus mackenziei | California |
| 277. | Madagapotamon humberti | Madagapotamon humberti | Madagascar |
| 278. | Madison Cave Isopod | Antrolana lira | Virginia, West Virginia |
| 279. | Mahatha helaya | Mahatha helaya | Sri Lanka |
| 280. | Mahatha iora | Mahatha iora | Sri Lanka |
| 281. | Mahatha lacuna | Mahatha lacuna | Sri Lanka |
| 282. | Mahatha regina | Mahatha regina | Sri Lanka |
| 283. | Mainitia mainitensis | Mainitia mainitensis | Philippines |
| 284. | Malayopotamon granulatum | Malayopotamon granulatum | Indonesia |
| 285. | Malheur Cave Amphipod | Stygobromus hubbsi | Oregon |
| 286. | Marron | Cherax tenuimanus | Australia |
| 287. | Mastigodiaptomus purpureus | Mastigodiaptomus purpureus | Cuba, Haiti |
| 288. | Maydelliathelphusa edentula | Maydelliathelphusa edentula | Bhutan, India |
| 289. | Mekhongthelphusa kengsaphu | Mekhongthelphusa kengsaphu | Thailand |
| 290. | Mekhongthelphusa tetragona | Mekhongthelphusa tetragona | Thailand |
| 291. | Mesocyclops insulensis | Mesocyclops insulensis | Madagascar |
| 292. | Metacyclops gasparoi | Metacyclops gasparoi | Italy |
| 293. | Metacyclops postojnae | Metacyclops postojnae | Slovenia |
| 294. | Metadiaptomus capensis | Metadiaptomus capensis | South Africa |
| 295. | Metadiaptomus purcelli | Metadiaptomus purcelli | South Africa |
| 296. | Metatrichoniscoides celticus | Metatrichoniscoides celticus | United Kingdom |
| 297. | Mexilana saluposi | Mexilana saluposi | Mexico |
| 298. | Mexistenasellus nulemex | Mexistenasellus nulemex | Mexico |
| 299. | Miami Cave Crayfish | Procambarus milleri | Florida |
| 300. | Microthelphusa forcarti | Microthelphusa forcarti | Venezuela |
| 301. | Mictacean | Mictocaris halope | Bermuda - North Atlantic Ocean |
| 302. | Migmathelphusa olivacea | Migmathelphusa olivacea | Indonesia (Sulawesi) |
| 303. | Minute Cave Amphipod | Stygobromus parvus | West Virginia |
| 304. | Mississippi Flatwoods Crayfish | Procambarus cometes | Mississippi |
| 305. | Miyazaki's Crab | Geothelphusa miyazakii | China, Taiwan |
| 306. | Mona Cave Shrimp | Typhlatya monae | Puerto Rico |
| 307. | Monolistra bolei | Monolistra bolei | Slovenia |
| 308. | Monolistra spinosissima | Monolistra spinosissima | Slovenia |
| 309. | Monolistra calopyge | Monolistra calopyge | Slovenia |
| 310. | Monolistra schottlaenderi | Monolistra schottlaenderi | Italy |
| 311. | Moritschus altaquerensis | Moritschus altaquerensis | Colombia |
| 312. | Moritschus ecuadorensis | Moritschus ecuadorensis | Ecuador |
| 313. | Morrison's Cave Amphipod | Stygobromus morrisoni | Virginia, West Virginia |
| 314. | Moserius percoi | Moserius percoi | Slovenia |
| 315. | Mountain Cave Amphipod | Stygobromus montanus | Arkansas |
| 316. | Muckalee Crayfish | Procambarus gibbus | Georgia |
| 317. | Nanocopia minuta | Nanocopia minuta | Bermuda - North Atlantic Ocean |
| 318. | Nautilothelphusa zimmeri | Nautilothelphusa zimmeri | Indonesia (Sulawesi) |
| 319. | Neches Crayfish | Procambarus nechesae | Texas |
| 320. | Nemoron nomas | Nemoron nomas | Vietnam |
| 321. | Neodiaptomus intermedius | Neodiaptomus intermedius | India |
| 322. | Neodiaptomus laii | Neodiaptomus laii | Malaysia |
| 323. | Neodiaptomus lymphatus | Neodiaptomus lymphatus | Indonesia |
| 324. | Neodiaptomus physalipus | Neodiaptomus physalipus | India |
| 325. | Neopseudothelphusa fossor | Neopseudothelphusa fossor | Venezuela |
| 326. | Neostrengeria perijaensis | Neostrengeria perijaensis | Colombia |
| 327. | Newnhamia fuscata | Newnhamia fuscata | Australia |
| 328. | Newnhamia insolita | Newnhamia insolita | Australia |
| 329. | Nickajack Cave Isopod | Caecidotea nickajackensis | Georgia, Tennessee |
| 330. | Nimba Stream Crab | Liberonautes nimba | Guinea, Liberia |
| 331. | Niphargobates lefkodemonaki | Niphargobates lefkodemonaki | Greece |
| 332. | Niphargobates orophobata | Niphargobates orophobata | Slovenia |
| 333. | Niphargus aberrans | Niphargus aberrans | Slovenia |
| 334. | Niphargus hadzii | Niphargus hadzii | Slovenia |
| 335. | Niphargus hrabei | Niphargus hrabei | Austria, Croatia, Hungary, Romania, Russia, Serbia, Slovakia, Ukraine |
| 336. | Niphargus sphagnicolus | Niphargus sphagnicolus | Slovenia |
| 337. | Niphargus spoeckeri | Niphargus spoeckeri | Slovenia |
| 338. | Niphargus stenopus | Niphargus stenopus | Slovenia |
| 339. | Niphargus timavi | Niphargus timavi | Italy, Slovenia |
| 340. | Niphargus valachicus | Niphargus valachicus | Bulgaria, Croatia, Hungary, Montenegro, Romania, Serbia, Slovakia, Slovenia, Turkey |
| 341. | Nitocrella slovenica | Nitocrella slovenica | Slovenia |
| 342. | Nitocrella stochi | Nitocrella stochi | Italy |
| 343. | Noel's Amphipod | Gammarus desperatus | New Mexico |
| 344. | Norton's Cave Amphipod | Stygobromus nortoni | Tennessee |
| 345. | Notodiaptomus dubius | Notodiaptomus dubius | Brazil |
| 346. | Notodiaptomus maracaibensis | Notodiaptomus maracaibensis | Brazil, Venezuela |
| 347. | Nueces Crayfish | Procambarus nueces | Texas |
| 348. | Obey Crayfish | Cambarus obeyensis | Tennessee |
| 349. | Oconee Burrowing Crayfish | Cambarus truncatus | United States |
| 350. | Oconee Stream Crayfish | Cambarus chaugaensis | Georgia, North Carolina, South Carolina |
| 351. | Okinawan Terrestrial Crab | Geothelphusa tenuimanus | Japan |
| 352. | Oklahoma Cave Amphipod | Allocrangonyx pellucidus | Oklahoma |
| 353. | Oklahoma Cave Crayfish | Cambarus tartarus | Oklahoma |
| 354. | Oktibbeha Riverlet Crayfish | Hobbseus orconectoides | Mississippi |
| 355. | Onchotelson brevicaudatus | Onchotelson brevicaudatus | Australia |
| 356. | Onchotelson spatulatus | Onchotelson spatulatus | Australia |
| 357. | Onondaga Cave Amphipod | Stygobromus onondagaensis | Arkansas, Kansas, Missouri, Oklahoma |
| 358. | Opossum Shrimp | Bermudamysis speluncola | Bermuda - North Atlantic Ocean |
| 359. | Orange Lake Cave Crayfish | Procambarus franzi | Florida |
| 360. | Orchid Island Crab | Geothelphusa lanyu | China, Taiwan |
| 361. | Orconectes shoupi | Orconectes shoupi | Tennessee |
| 362. | Orconectes saxatilis | Orconectes saxatilis | Oklahoma |
| 363. | Orconectes bisectus | Orconectes bisectus | Kentucky |
| 364. | Orconectes blacki | Orconectes blacki | Louisiana |
| 365. | Orconectes cooperi | Orconectes cooperi | Alabama, Tennessee |
| 366. | Orconectes deanae | Orconectes deanae | New Mexico, Oklahoma, Texas |
| 367. | Orconectes hartfieldi | Orconectes hartfieldi | Mississippi |
| 368. | Orconectes holti | Orconectes holti | Alabama |
| 369. | Orconectes incomptus | Orconectes incomptus | Tennessee |
| 370. | Orconectes jeffersoni | Orconectes jeffersoni | Kentucky |
| 371. | Orconectes jonesi | Orconectes jonesi | Alabama, Mississippi |
| 372. | Orconectes kentuckiensis | Orconectes kentuckiensis | Illinois, Kentucky |
| 373. | Orconectes maletae | Orconectes maletae | Louisiana, Texas |
| 374. | Orconectes marchandi | Orconectes marchandi | Arkansas, Missouri |
| 375. | Orconectes menae | Orconectes menae | Arkansas, Oklahoma |
| 376. | Orconectes mississippiensis | Orconectes mississippiensis | Mississippi |
| 377. | Orconectes peruncus | Orconectes peruncus | Missouri |
| 378. | Orconectes quadruncus | Orconectes quadruncus | Missouri |
| 379. | Orconectes sloanii | Orconectes sloanii | Indiana, Ohio |
| 380. | Orconectes stannardi | Orconectes stannardi | Illinois |
| 381. | Orconectes wrighti | Orconectes wrighti | Mississippi, Tennessee |
| 382. | Orlando Cave Crayfish | Procambarus acherontis | Florida |
| 383. | Ouachita Burrowing Crayfish | Fallicambarus harpi | Arkansas |
| 384. | Ozark Cave Amphipod | Stygobromus ozarkensis | Arkansas, Missouri, Oklahoma |
| 385. | Oziothelphusa dakuna | Oziothelphusa dakuna | Sri Lanka |
| 386. | Oziothelphusa gallicola | Oziothelphusa gallicola | Sri Lanka |
| 387. | Oziothelphusa intuta | Oziothelphusa intuta | Sri Lanka |
| 388. | Oziothelphusa kodagoda | Oziothelphusa kodagoda | Sri Lanka |
| 389. | Oziothelphusa populosa | Oziothelphusa populosa | Sri Lanka |
| 390. | Oziothelphusa biloba | Oziothelphusa biloba | India |
| 391. | Oziothelphusa hippocastanum | Oziothelphusa hippocastanum | Sri Lanka |
| 392. | Oziothelphusa ritigala | Oziothelphusa ritigala | Sri Lanka |
| 393. | Oziothelphusa stricta | Oziothelphusa stricta | Sri Lanka |
| 394. | Oziothelphusa wagrakarowensis | Oziothelphusa wagrakarowensis | India |
| 395. | Panama City Crayfish | Procambarus econfinae | Florida |
| 396. | Paracyclopia naessi | Paracyclopia naessi | Bermuda - North Atlantic Ocean |
| 397. | Paradiaptomus natalensis | Paradiaptomus natalensis | South Africa |
| 398. | Paramelita barnardi | Paramelita barnardi | South Africa |
| 399. | Paramelita flexa | Paramelita flexa | South Africa |
| 400. | Paramorariopsis anae | Paramorariopsis anae | Slovenia |
| 401. | Parapotamon spinescens | Parapotamon spinescens | China (Yunnan) |
| 402. | Parathelphusa batamensis | Parathelphusa batamensis | Indonesia |
| 403. | Parathelphusa nagasakti | Parathelphusa nagasakti | Malaysia |
| 404. | Parathelphusa reticulata | Parathelphusa reticulata | Singapore |
| 405. | Parathelphusa balabac | Parathelphusa balabac | Philippines |
| 406. | Parathelphusa cabayugan | Parathelphusa cabayugan | Philippines |
| 407. | Parathelphusa crocea | Parathelphusa crocea | Indonesia |
| 408. | Parathelphusa maindroni | Parathelphusa maindroni | Indonesia, Malaysia |
| 409. | Parathelphusa ovum | Parathelphusa ovum | Malaysia |
| 410. | Parathelphusa pantherina | Parathelphusa pantherina | Indonesia |
| 411. | Parathelphusa possoensis | Parathelphusa possoensis | Indonesia |
| 412. | Parathelphusa sarasinorum | Parathelphusa sarasinorum | Indonesia |
| 413. | Parkhill Prairie Crayfish | Procambarus steigmani | Texas |
| 414. | Parzefall's Stenasellid | Mexistenasellus parzefalli | Mexico |
| 415. | Pastilla dacuna | Pastilla dacuna | Sri Lanka |
| 416. | Pearl Riverlet Crayfish | Hobbseus attenuatus | Mississippi |
| 417. | Peck's Cave Amphipod | Stygobromus pecki | Texas |
| 418. | Pecos Amphipod | Gammarus pecos | Texas |
| 419. | Pennsylvania Cave Amphipod | Crangonyx dearolfi | Maryland, Pennsylvania |
| 420. | Perbrinckia cracens | Perbrinckia cracens | Sri Lanka |
| 421. | Perbrinckia enodis | Perbrinckia enodis | Sri Lanka |
| 422. | Perbrinckia fido | Perbrinckia fido | Sri Lanka |
| 423. | Perbrinckia gabadagei | Perbrinckia gabadagei | Sri Lanka |
| 424. | Perbrinckia glabra | Perbrinckia glabra | Sri Lanka |
| 425. | Perbrinckia morayensis | Perbrinckia morayensis | Sri Lanka |
| 426. | Perbrinckia punctata | Perbrinckia punctata | Sri Lanka |
| 427. | Perbrinckia quadratus | Perbrinckia quadratus | Sri Lanka |
| 428. | Perbrinckia rosae | Perbrinckia rosae | Sri Lanka |
| 429. | Perbrinckia scitula | Perbrinckia scitula | Sri Lanka |
| 430. | Perbrinckia fenestra | Perbrinckia fenestra | Sri Lanka |
| 431. | Perbrinckia integra | Perbrinckia integra | Sri Lanka |
| 432. | Phantom Cave Crayfish | Procambarus pecki | Alabama |
| 433. | Phricotelphusa gracilipes | Phricotelphusa gracilipes | Malaysia |
| 434. | Phricotelphusa hockpingi | Phricotelphusa hockpingi | Malaysia |
| 435. | Phricotelphusa callianira | Phricotelphusa callianira | Myanmar, Thailand |
| 436. | Phricotelphusa elegans | Phricotelphusa elegans | Myanmar |
| 437. | Phricotelphusa limula | Phricotelphusa limula | Thailand |
| 438. | Phricotelphusa ranongi | Phricotelphusa ranongi | Thailand |
| 439. | Phrygiopilus acanthophallus | Phrygiopilus acanthophallus | Guatemala |
| 440. | Phyllodiaptomus wellekensae | Phyllodiaptomus wellekensae | India |
| 441. | Pickle Springs Amphipod | Stygobromus heteropodus | Missouri |
| 442. | Piedmont Blue Burrower | Cambarus harti | Georgia |
| 443. | Pingtung Crab | Geothelphusa pingtung | China, Taiwan |
| 444. | Pizzini's Amphipod | Stygobromus pizzinii | District of Columbia, Maryland, Pennsylvania, Virginia |
| 445. | Platyops sterreri | Platyops sterreri | Bermuda - North Atlantic Ocean |
| 446. | Potamocarcinus hartmanni | Potamocarcinus hartmanni | Mexico |
| 447. | Potamocarcinus roatensis | Potamocarcinus roatensis | Honduras |
| 448. | Potamon bileki | Potamon bileki | Asia, Europe, Middle East |
| 449. | Potamon fluviatile | Potamon fluviatile | Asia, Europe |
| 450. | Potamon ibericum | Potamon ibericum | Asia, Europe, Middle East |
| 451. | Potamon potamios | Potamon potamios | Africa, Asia, Europe, Middle East |
| 452. | Potamon rhodium | Potamon rhodium | Asia, Europe, Middle East |
| 453. | Potamon setiger | Potamon setiger | Asia, Europe, Middle East |
| 454. | Potamonautes gonocristatus | Potamonautes gonocristatus | Democratic Republic of Congo (Zaire), Uganda |
| 455. | Potamonautes idjiwiensis | Potamonautes idjiwiensis | Democratic Republic of Congo (Zaire) |
| 456. | Potamonautes mutandensis | Potamonautes mutandensis | Uganda |
| 457. | Potamonautes platycentron | Potamonautes platycentron | Kenya, Tanzania |
| 458. | Potamonautes choloensis | Potamonautes choloensis | Malawi |
| 459. | Potamonautes gerdalensis | Potamonautes gerdalensis | Kenya, Tanzania |
| 460. | Potamonautes ignestii | Potamonautes ignestii | Ethiopia, Uganda |
| 461. | Potamonautes infravallatus | Potamonautes infravallatus | Tanzania |
| 462. | Potamonautes lividus | Potamonautes lividus | South Africa |
| 463. | Potamonautes montivagus | Potamonautes montivagus | Malawi |
| 464. | Potamonautes pilosus | Potamonautes pilosus | Kenya, Tanzania |
| 465. | Potamonautes raybouldi | Potamonautes raybouldi | Kenya, Tanzania |
| 466. | Potamonautes reidi | Potamonautes reidi | Nigeria |
| 467. | Potamonautes triangulus | Potamonautes triangulus | Ghana |
| 468. | Potamonautes unisulcatus | Potamonautes unisulcatus | Tanzania |
| 469. | Potamonautes xiphoidus | Potamonautes xiphoidus | Tanzania |
| 470. | Pristine Crayfish | Cambarus pristinus | Tennessee |
| 471. | Proasellus parvulus | Proasellus parvulus | Slovenia |
| 472. | Proasellus slovenicus | Proasellus slovenicus | Slovenia |
| 473. | Procambarus latipleurum | Procambarus latipleurum | Florida |
| 474. | Procambarus plumimanus | Procambarus plumimanus | North Carolina |
| 475. | Procambarus rathbunae | Procambarus rathbunae | Florida |
| 476. | Procambarus reimeri | Procambarus reimeri | Arkansas |
| 477. | Procarid Shrimp | Procaris chacei | Bermuda - North Atlantic Ocean |
| 478. | Pseudocandona cavicola | Pseudocandona cavicola | Slovenia |
| 479. | Pseudocandona pretneri | Pseudocandona pretneri | Slovenia |
| 480. | Pseudocandona trigonelia | Pseudocandona trigonelia | Slovenia |
| 481. | Pseudomoraria triglavensis | Pseudomoraria triglavensis | Slovenia |
| 482. | Ptychophallus tristani | Ptychophallus tristani | Costa Rica |
| 483. | Pupamon phrae | Pupamon phrae | Thailand |
| 484. | Purple Marsh Crab | Afrithelphusa monodosa | Guinea |
| 485. | Putnam County Cave Crayfish | Procambarus morrisi | Florida |
| 486. | Raddaus mertensi | Raddaus mertensi | El Salvador, Guatemala, Honduras |
| 487. | Red-black Crayfish | Cambarus pyronotus | Florida |
| 488. | Redclaw Crayfish | Cherax quadricarinatus | Australia |
| 489. | Reddell's Cave Amphipod | Stygobromus reddelli | Texas |
| 490. | Rhynchochydorus australiensis | Rhynchochydorus australiensis | Australia |
| 491. | Rodriguezus trujillensis | Rodriguezus trujillensis | Venezuela |
| 492. | Rusty Grave Digger | Cambarus miltus | Alabama, Florida |
| 493. | Rye Cove Cave Isopod | Lirceus culveri | Virginia |
| 494. | Sachs's Stream Crab | Potamonemus sachsi | Cameroon, Nigeria |
| 495. | Salangathelphusa anophrys | Salangathelphusa anophrys | Thailand |
| 496. | Saline Burrowing Crayfish | Fallicambarus strawni | Arkansas |
| 497. | San Diego Fairy Shrimp | Branchinecta sandiegonensis | California |
| 498. | Sandhills Crayfish | Procambarus angustatus | Georgia |
| 499. | Santa Fe Cave Crayfish | Procambarus erythrops | Florida |
| 500. | Sayamia melanodactylus | Sayamia melanodactylus | Thailand |
| 501. | Sayamia maehongsonensis | Sayamia maehongsonensis | Thailand |
| 502. | Seed Shrimp | Limnocythere porphyretica | Australia |
| 503. | Shasta Crayfish | Pacifastacus fortis | California |
| 504. | Siamthelphusa holthuisi | Siamthelphusa holthuisi | Thailand |
| 505. | Silver Glen Springs Cave Crayfish | Procambarus attiguus | Florida |
| 506. | Sinopotamon ebianense | Sinopotamon ebianense | China |
| 507. | Sinopotamon hanyangense | Sinopotamon hanyangense | China |
| 508. | Skistodiaptomus carolinensis | Skistodiaptomus carolinensis | North Carolina |
| 509. | Slenderwrist Burrowing Crayfish | Fallicambarus petilicarpus | Arkansas |
| 510. | Socorro Isopod | Thermosphaeroma thermophilum | New Mexico |
| 511. | Somanniathelphusa zanklon | Somanniathelphusa zanklon | Hong Kong |
| 512. | Somersiella sterreri | Somersiella sterreri | Bahamas, Bermuda - North Atlantic Ocean, Cuba, Mexico |
| 513. | Sooty Crayfish | Pacifastacus nigrescens | California |
| 514. | South Australia Crab | Geothelphusa nanao | China, Taiwan |
| 515. | Speckled Burrowing Crayfish | Fallicambarus danielae | Alabama, Mississippi |
| 516. | Spelaeoecia bermudensis | Spelaeoecia bermudensis | Bermuda - North Atlantic Ocean |
| 517. | Speleoithona bermudensis | Speleoithona bermudensis | Bermuda - North Atlantic Ocean |
| 518. | Speleophria bivexilla | Speleophria bivexilla | Bermuda - North Atlantic Ocean |
| 519. | Speleophria scottodicarloi | Speleophria scottodicarloi | Bermuda - North Atlantic Ocean |
| 520. | Speocirolana thermydromis | Speocirolana thermydromis | Mexico |
| 521. | Sphaerolana affinis | Sphaerolana affinis | Mexico |
| 522. | Sphaerolana interstitialis | Sphaerolana interstitialis | Mexico |
| 523. | Sphaerolana karenae | Sphaerolana karenae | Mexico |
| 524. | Spiny Crayfish | Euastacus bindal | Australia |
| 525. | Spiny Crayfish | Euastacus crassus | Australia |
| 526. | Spiny Crayfish | Euastacus diversus | Australia |
| 527. | Spiny Crayfish | Euastacus jagara | Australia |
| 528. | Spiny Crayfish | Euastacus maidae | Australia |
| 529. | Spiny Crayfish | Euastacus monteithorum | Australia |
| 530. | Spiny Crayfish | Euastacus robertsi | Australia |
| 531. | Spiny Crayfish | Euastacus urospinosus | Australia |
| 532. | Spiny Crayfish | Euastacus yigara | Australia |
| 533. | Spiny Crayfish | Euastacus armatus | Australia |
| 534. | Spiny Crayfish | Euastacus bispinosus | Australia |
| 535. | Spiny Crayfish | Euastacus eungella | Australia |
| 536. | Spiny Crayfish | Euastacus fleckeri | Australia |
| 537. | Spiny Crayfish | Euastacus hystricosus | Australia |
| 538. | Spiny Crayfish | Euastacus neodiversus | Australia |
| 539. | Spiny Crayfish | Euastacus setosus | Australia |
| 540. | Spiny-tail Crayfish | Procambarus fitzpatricki | Mississippi |
| 541. | Spiralothelphusa fernandoi | Spiralothelphusa fernandoi | Sri Lanka |
| 542. | Spiralothelphusa parvula | Spiralothelphusa parvula | Sri Lanka |
| 543. | Spring Cave Amphipod | Stygobromus spinatus | West Virginia |
| 544. | Stellmack's Cave Amphipod | Stygobromus stellmacki | Pennsylvania |
| 545. | Stelomon erawanense | Stelomon erawanense | Thailand |
| 546. | Stelomon kanchanaburiense | Stelomon kanchanaburiense | Thailand |
| 547. | Stoliczia chaseni | Stoliczia chaseni | Malaysia |
| 548. | Stoliczia bella | Stoliczia bella | Malaysia |
| 549. | Stoliczia changmanae | Stoliczia changmanae | Malaysia |
| 550. | Stoliczia cognata | Stoliczia cognata | Malaysia |
| 551. | Stoliczia goal | Stoliczia goal | Malaysia |
| 552. | Stoliczia karenae | Stoliczia karenae | Malaysia |
| 553. | Stoliczia kedahensis | Stoliczia kedahensis | Malaysia |
| 554. | Stoliczia leoi | Stoliczia leoi | Malaysia |
| 555. | Stoliczia pahangensis | Stoliczia pahangensis | Malaysia |
| 556. | Stoliczia panhai | Stoliczia panhai | Thailand |
| 557. | Stoliczia perlensis | Stoliczia perlensis | Malaysia |
| 558. | Stoliczia tweedei | Stoliczia tweedei | Malaysia |
| 559. | Stone Crayfish | Austropotamobius torrentium | Asia, Europe |
| 560. | Strengeriana antioquensis | Strengeriana antioquensis | Colombia |
| 561. | Streptocephalus woottoni | Streptocephalus woottoni | California |
| 562. | Streptocephalus moorei | Streptocephalus moorei | Mexico |
| 563. | Streptocephalus dendrophorus | Streptocephalus dendrophorus | South Africa |
| 564. | Streptocephalus dendyi | Streptocephalus dendyi | South Africa |
| 565. | Streptocephalus gracilis | Streptocephalus gracilis | South Africa |
| 566. | Streptocephalus guzmani | Streptocephalus guzmani | Mexico |
| 567. | Streptocephalus zuluensis | Streptocephalus zuluensis | South Africa, Zimbabwe |
| 568. | Stygodiaptomus kieferi | Stygodiaptomus kieferi | Bosnia and Herzegovina |
| 569. | Stygodiaptomus petkovskii | Stygodiaptomus petkovskii | Bosnia and Herzegovina, Croatia |
| 570. | Stygothelphusa bidiensis | Stygothelphusa bidiensis | Malaysia (Sarawak) |
| 571. | Subtle Cave Amphipod | Stygobromus subtilis | Illinois, Michigan, Missouri |
| 572. | Sundathelphusa sottoae | Sundathelphusa sottoae | Philippines |
| 573. | Sundathelphusa minahassae | Sundathelphusa minahassae | Indonesia (Sulawesi) |
| 574. | Sundathelphusa rubra | Sundathelphusa rubra | Indonesia (Sulawesi) |
| 575. | Syncarid Shrimp | Allanaspides helonomus | Australia (Tasmania) |
| 576. | Taiwan Waist Crab | Somanniathelphusa taiwanensis | China, Taiwan |
| 577. | Taiwan's South China Sea River Crab | Nanhaipotamon formosanum | China, Taiwan |
| 578. | Taroko Crab | Geothelphusa taroko | China, Taiwan |
| 579. | Tasmanian Anaspid Crustacean | Paranaspides lacustris | Australia |
| 580. | Tehuana lamothei | Tehuana lamothei | Mexican Holarctic |
| 581. | Tehuana poglayenorum | Tehuana poglayenorum | Mexican Holarctic |
| 582. | Tehuana veracruzana | Tehuana veracruzana | Mexican Holarctic |
| 583. | Terrathelphusa kuchingensis | Terrathelphusa kuchingensis | Malaysia |
| 584. | Thaksinthelphusa yongchindaratae | Thaksinthelphusa yongchindaratae | Thailand |
| 585. | Thermodiaptomus galeboides | Thermodiaptomus galeboides | Kenya, Tanzania, Uganda |
| 586. | Thermosphaeroma cavicauda | Thermosphaeroma cavicauda | Mexico |
| 587. | Thermosphaeroma dugesi | Thermosphaeroma dugesi | Mexico |
| 588. | Thermosphaeroma macrura | Thermosphaeroma macrura | Mexico |
| 589. | Thermosphaeroma milleri | Thermosphaeroma milleri | Mexico |
| 590. | Thermosphaeroma smithi | Thermosphaeroma smithi | Mexico |
| 591. | Tidewater Interstitial Amphipod | Stygobromus araeus | North Carolina, Virginia |
| 592. | Tidewater Stygonectid Amphipod | Stygobromus identatus | Maryland, North Carolina |
| 593. | Tiwaripotamon edostilus | Tiwaripotamon edostilus | Vietnam |
| 594. | Tombigbee Riverlet Crayfish | Hobbseus petilus | Mississippi |
| 595. | Tree Hole Crab | Globonautes macropus | Guinea, Liberia |
| 596. | Trichodactylus crassus | Trichodactylus crassus | Brazil |
| 597. | Troglocaris anophthalmus | Troglocaris anophthalmus | Bosnia and Herzegovina, Croatia, Italy, Slovenia |
| 598. | Tropocyclops federensis | Tropocyclops federensis | Brazil |
| 599. | Tropocyclops nananae | Tropocyclops nananae | Brazil |
| 600. | Tropodiaptomus burundensis | Tropodiaptomus burundensis | Burundi |
| 601. | Tropodiaptomus kilimensis | Tropodiaptomus kilimensis | Tanzania |
| 602. | Tropodiaptomus kissi | Tropodiaptomus kissi | Rwanda |
| 603. | Tropodiaptomus neumanni | Tropodiaptomus neumanni | Kenya |
| 604. | Tropodiaptomus simplex | Tropodiaptomus simplex | Burundi, Democratic Republic of Congo (Zaire), Tanzania |
| 605. | Tropodiaptomus stuhlmanni | Tropodiaptomus stuhlmanni | Kenya, Tanzania, Uganda |
| 606. | Typhlopseudothelphusa mocinoi | Typhlopseudothelphusa mocinoi | Mexico |
| 607. | Uramphisopus pearsoni | Uramphisopus pearsoni | Australia (Tasmania) |
| 608. | Valley Flame Crayfish | Cambarus deweesae | Kentucky, Tennessee |
| 609. | Vernal Pool Fairy Shrimp | Branchinecta lynchi | California, Oregon |
| 610. | Vernal Pool Tadpole Shrimp | Lepidurus packardi | California |
| 611. | Wang's Crab | Geothelphusa wangi | China, Taiwan |
| 612. | Water Flea | Daphnia coronata | South Africa |
| 613. | Water Flea | Daphnia jollyi | Australia |
| 614. | Water Flea | Daphnia nivalis | Australia |
| 615. | Water Flea | Daphnia occidentalis | Australia |
| 616. | Wengeror's Cave Amphipod | Stygobromus wengerorum | California |
| 617. | White-clawed Crayfish | Austropotamobius pallipes | Austria, Bosnia and Herzegovina, Croatia, France, Ireland, Italy, Portugal, Slovenia, Spain, Switzerland, United Kingdom |
| 618. | Wilken's Stenasellid | Mexistenasellus wilkensi | Mexico |
| 619. | Wisconsin Well Amphipod | Stygobromus putealis | Wisconsin |
| 620. | Woodville Cave Crayfish | Procambarus orcinus | Florida |
| 621. | Wutai Crab | Geothelphusa wutai | China, Taiwan |
| 622. | Yalobusha Riverlet Crayfish | Hobbseus yalobushensis | Mississippi |
| 623. | Yangmingshan Crab | Geothelphusa yangminshan | China, Taiwan |
| 624. | Ze Concept Of Crab | Geothelphusa takuan | China, Taiwan |
| 625. | Zonocypretta kalimna | Zonocypretta kalimna | Australia |
