| Main Ref. | Masuda, H., K. Amaoka, C. Araga, T. Uyeno and T. Yoshino, 1984 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | none |
| Body shape lateral | elongated |
| Cross section | oval |
| Dorsal head profile | clearly convex |
| Type of eyes | more or less normal |
| Type of mouth/snout | more or less normal |
| Position of mouth | terminal |
| Type of scales | |
| Diagnosis |
Body nearly cylindrical anteriorly, but compressed posteriorly. Head large, more than one-third of SL in length. Maxillary extending to middle of eye. Scales small, more than 65 in lateral line. Jet black head entirely naked. |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | 67 - 70 |
| 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 | 18 - 20 |
| on upper limb | 9 - 9 |
| total | |
| Vertebrae | |
| preanal | 58 - 59 |
| total |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 17 - 18 |
| Adipose fin | absent |
| Attributes | forked; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 17 - 18 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 10 - 11 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays |