| Main Ref. | Last, P.R. and J.D. Stevens, 1994 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral (shape guide) | elongated |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | placoid scales |
| Diagnosis |
Eel-like shark with 6 gill slits, the lower ends of the first gill slits connected t each other across throat (Ref. 247). Dark brown or grey in color, sometimes paler below (Ref. 26346). Dorsal fin small and lobe-like originating over pelvic fin bases to behind anal fin origin (Ref. 6871). Anal fin larger than dorsal fin (Ref. 6871). Pectoral fins small and paddle-shaped (Ref. 6871). Caudal fin with weak ventral lobe and without subterminal notch (Ref. 6871). Terminal mouth with tricuspid teeth in both jaws (Ref. 247). |
| 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 | |
| Vertebrae | |
| preanal | |
| total | 146 - 171 |
| Attributes | |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 0 - 0 |
| Adipose fin | absent |
| Attributes | other (see remark) |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 0 - 0 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 0 - 0 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines 0 | |
| Soft-rays 0 - 0 |