| 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 | circular |
| Dorsal head profile | more or less straight |
| Type of eyes | more or less normal |
| Type of mouth/snout | tube-like |
| Position of mouth | superior |
| Type of scales | |
| Diagnosis |
Characterized by having a horizontal skin fold along its ventral contour, and the absence of pelvic fin and teeth. Lateral plicae 160 to 180. Lower jaw pointed. Lateral line system on head not continuous with that on the body. |
| 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 | 0 |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | 20 - 23 |
| on upper limb | 4 - 6 |
| total | |
| Vertebrae | |
| preanal | 38 - 43 |
| total | 62 - 67 |
| Attributes | extending over most of the back length |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 55 - 59 |
| Adipose fin | absent |
| Attributes | forked; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 28 - 32 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 15 - 16 | |
| Pelvics | Attributes |
| Position | |
| Spines | |
| Soft-rays |