| Main Ref. | Littmann, M.W., B.M. Burr, R.E. Schmidt and E.R. Isern, 2001 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral | elongated |
| Cross section | circular |
| Dorsal head profile | more or less straight |
| Type of eyes | other (see remarks) |
| Type of mouth/snout | upper jaw greatly elongated |
| Position of mouth | sub-terminal/inferior |
| Type of scales | |
| Diagnosis |
Laterally positioned eyes, visible dorsally and ventrally; in adults, the diameter is 2.2-3.3 times into interorbital width. Inner mental barbels usually posterior to gular apex, rarely even with it, and never reaching fleshy margin of opercle. Outer mental barbels longer, extending beyond the origin of pectoral fins. Maxillary barbels variable in length, extending to pelvic fins or beyond. Pelvic fins when depressed reaching approximately halfway from anus to anal-fin origin. |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | |
| Scale rows below lateral line | |
| Scales around caudal peduncle | |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | 15 - 23 |
| Vertebrae | |
| preanal | |
| total | 44 - 46 |
| Attributes | |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | |
| Soft-rays total | 6 - 6 |
| Adipose fin | present |
| Attributes | more or less truncate; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 20 - 25 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 7 - 9 | |
| Pelvics | Attributes more or less normal |
| Position abdominal behind origin of D1 | |
| Spines 1 | |
| Soft-rays 5 - 5 |