| Main Ref. | Hart, J.L., 1973 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral (shape guide) | eel-like |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
First 5 rays of dorsal fin greatly elongated in young becoming reduced with age, otherwise rather higher in center, extending almost to caudal and ends abruptly (Ref. 6885); caudal fin highly asymmetric, dorsal lobe becomes well developed in juveniles with 7-8 rays directed upward at an angle of 45° to body axis, and eventually with growth is much reduced; ventral lobe elongate in young specimens becoming reduced to 5-6 spines directed backward from the caudal base in older individuals; anal fin absent; pectorals small, rounded; pelvic fins elongate in young and juveniles, reduced to base in larger individuals (Ref. 6885). Juveniles iridescent silvery with a series of about 4 dark blotches spaced above lateral line canal; upright and pelvic fins carmine red; larger individuals rather very silvery and greener with light spots, around scales; posterior end of dorsal fin darker (Ref. 6885). |
| 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 | 9 - 11 |
| on upper limb | 3 - 5 |
| total | 12 - 16 |
| Vertebrae | |
| preanal | |
| total | 90 - 94 |
| 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 | 165 - 184 |
| Adipose fin | absent |
| Attributes | other (see remark); asymmetric |
| Fins number | |
| Spines total | 0 - 0 |
| Soft-rays total | 0 - 0 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 10 - 11 | |
| Pelvics | Attributes other (see diagnosis) |
| Position thoracic | |
| Spines 0 | |
| Soft-rays 6 - 7 |