Identification keys available for Order Ophidiiformes
| Key | Title |
| 944 | Key to the species of pearlfishes (Carapidae) occurring in the Western Central Atlantic. |
| 945 | Key to subfamilies of cusk-eels (Ophidiidae) occurring in the Western Central Atlantic. |
| 946 | Key to species of Brotulotaeniinae occurring in the Western Central Atlantic. |
| 947 | Key to tribes of Ophidiinae occurring in the Western Central Atlantic. |
| 948 | Key to the genera of Ophidiini occurring in the Western Central Atlantic. |
| 949 | Key to the species of Otophidium occurring in the Western Central Atlantic. |
| 1340 | Key to suborders of Ophidiiformes of the world. |
| 1341 | Key to the families of suborder Ophidioidei of the world. |
| 1342 | Key to the genera of Carapidae of the world. |
| 1343 | Key to species of Carapus of the world. |
| 1344 | Key to species of Echiodon of the world. |
| 1345 | Key to species of Encheliophis of the world. |
| 1346 | Key to species of Onuxodon of the world. |
| 1347 | Key to species of Pyramodon of the world. |
| 1348 | Key to subfamilies of Ophidiidae of the world. |
| 1349 | Key to the species of Brotulotaenia of the world. |
| 1350 | Key to tribes of Ophidiinae of the world. |
| 1351 | Key to the genera of Lepophidiinae of the world. |
| 1352 | Key to species of Lepophidium. |
| 1353 | Key to the genera of Ophidiini of the world. |
| 1354 | Key to the genera of Neobythitinae. |
| 1355 | Key to species of Apagesoma. |
| 1356 | Key to species of Barathrites. |
| 1357 | Key to species of Barathrodemus. |
| 1358 | Key to species of Bassozetus. |
| 1359 | Key to species of Dicrolene. |
| 1360 | Key to species of Enchelybrotula. |
| 1361 | Key to species of Glyptophidium. |
| 1362 | Key to species of Hoplobrotula. |
| 1363 | Key to species of Lamprogrammus. |
| 1364 | Key to species of Leucicorus. |
| 1365 | Key to species of Luciobrotula. |
| 1366 | Key to species of Mastigopterus. |
| 1367 | Key to species of Monomitopus. |
| 1368 | Key to species of Neobythites occurring in West Atlantic Ocean. |
| 1369 | Key to species of Neobythites occurring in Western Indian Ocean. |
| 1370 | Key to species of Neobythites occurring in New Caledonia. |
| 1371 | Key to species of Petrotyx. |
| 1372 | Key to species of Porogadus occurring in West Atlantic. |
| 1373 | Key to species of Sirembo. |
| 1374 | Key to species of Spottobrotula. |
| 1376 | Key to subfamilies of Bythitidae. |
| 1377 | Key to genera of Bythitinae. |
| 1378 | Key to species of Bythites. |
| 1379 | Key to species of Calamopteryx. |
| 1380 | Key to species of Cataetyx. |
| 1381 | Key to species of Grammonus. |
| 1382 | Key to species of Hephthocara. |
| 1383 | Key to species of Microbrotula. |
| 1384 | Key to species of Pseudonus. |
| 1385 | Key to species of Saccogaster. |
| 1386 | Key to species of Thalassobathia. |
| 1387 | Key to genera of Brosmophycinae including referral to tribe. |
| 1388 | Key to genera of Brosmophycinae without referral to tribe. |
| 1389 | Key to species of Bidenichthys. |
| 1390 | Key to species of Lucifuga. |
| 1391 | Key to species of Melodichthys. |
| 1394 | Key to species of Dermatopsis. |
| 1395 | Key to species of Dermatopsoides. |
| 1396 | Key to species of Dipulus. |
| 1397 | Key to genera of Aphyonidae. |
| 1398 | Key to species of Aphyonus. |
| 1399 | Key to species Nybelinella |
| 1400 | Key to species Parasciadonus. |