| Main Ref. | Teugels, G.G., 1986 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | no special organs |
| Different appearance | males alike females |
| Different colors | males alike females |
| 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 | more or less normal |
| Position of mouth | sub-terminal/inferior |
| Type of scales | scales embedded or partly/completely absent |
| Diagnosis |
Devoid of pigment. Eyes extremely small; covered with skin; dorsally located. Head rectangular in dorsal outline; snout broadly rounded. Frontal fontanelle long and narrow; occipital fontanelle long and oval-shaped. Supraorbital and `dermosphenotic' bones fused. Premaxillary tooth plate rather broad. gill rakers long, slender and distantly set. Suprabranchial organ greatly reduced. Openings of the secondary sensory canals regularly arranged along flanks. |
| Ease of Identification |
| Lateral Lines | 1 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) | absent |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | 12 - 15 |
| Vertebrae | |
| preanal | |
| total |
| Attributes | extending over most of the back length |
| Fins number | 1 |
| Finlets No. | Dorsal 0 |
| Ventral 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 71 - 76 |
| Adipose fin | absent |
| Attributes | more or less truncate; more or less normal |
| Fins number | 1 |
| Spines total | |
| Soft-rays total | 66 - 61 |
| Pectoral | Attributes more or less normal |
| Spines 1 | |
| Soft-rays 8 - 9 | |
| Pelvics | Attributes more or less normal |
| Position abdominal behind origin of D1 | |
| Spines | |
| Soft-rays 6 |