| Main Ref. | Page, L.M. and B.M. Burr, 1991 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral | elongated |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
Pink-white. No eyes (vestigial eye tissues under skin). Extremely small pelvic fins (rarely absent). Large, broad head. Caudal fin with 4-6 rows of papillae; 11-13 branched caudal rays. |
| Ease of Identification |
| Lateral Lines | 1 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 | 7 - 7 |
| Vertebrae | |
| preanal | |
| total | 29 - 30 |
| Attributes | |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 9 - 11 |
| Adipose fin | absent |
| Attributes | more or less truncate; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 8 - 11 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 9 - 11 | |
| Pelvics | Attributes |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays |