| Main Ref. | Fischer, W. and G. Bianchi (eds.), 1984 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | no special organs |
| Different appearance | males alike females |
| Different colors | males alike females |
| Remarks |
| Striking features | striking fins |
| Body shape lateral | short and / or deep |
| 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 |
Scales enlarged above the pectoral fin base and just behind the gill slit to form a flexible tympanum; scales of posterior body with prominent keels, forming longitudinal ridges. A prominent groove in the skin extending anteriorly from front of eye for a distance of about 1 eye diameter. Caudal peduncle depressed. Caudal fin rays of adults prolonged above and below. |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | |
| Scales in lateral series | 33 - 41 |
| 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 | |
| Vertebrae | |
| preanal | |
| total |
| Attributes | first rays forming locking device |
| Fins number | 2 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 3 - 3 |
| Soft-rays total | 25 - 27 |
| Adipose fin | absent |
| Attributes | more or less truncate; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 24 - 26 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 13 - 16 | |
| Pelvics | Attributes joint to one spine only |
| Position abdominal behind origin of D1 | |
| Spines | |
| Soft-rays |