| Main Ref. | Skelton, P.H., 2001 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | none |
| Body shape lateral | eel-like |
| Cross section | circular |
| Dorsal head profile | more or less straight |
| Type of eyes | more or less normal |
| Type of mouth/snout | more or less normal |
| Position of mouth | terminal |
| Type of scales | |
| Diagnosis |
Description: Head and body elongated, with thick smooth skin, scales minute and embedded (Ref. 52193). Dorsal fin origin well in advance of anal fin origin, both joined with caudal (Ref. 4967, 52193). Mouth large, lips thick, teeth fine, forming narrow bands on jaws and palate; gill slits small, restricted to sides in front of pectoral fins (Ref. 52193). Colouration: Olive to greyish black dorsally, lighter ventrally (Ref. 3971, 52193). On maturity prior to entering the sea the colour changes to dark bronze above and light yellow or silvery below (Ref. 52193). |
| 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 | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| total |
| Attributes | continuous with caudal fin |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | |
| Adipose fin | absent |
| Attributes | other (see diagnosis) |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays | |
| Pelvics | Attributes suppressed/absent |
| Position absent | |
| Spines 0 | |
| Soft-rays 0 - 0 |