| Main Ref. | Palsson, W.A. and T.W. Pietsch, 1989 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | flaps |
| Body shape lateral | other |
| Cross section | flattened |
| 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 | bony plates or armour |
| Diagnosis |
Body light to dark brown, olive or blue dorsally and laterally, light brown ventrally. Tail rings 14, anteriormost 7 mobile, remaining 7 fused; terminal tail rings with dorsal and ventral pairs of posteriorly directed spines; rostrum square in cross section; interpectoral plate absent. 4 pairs dorsolateral body plates; 5 pairs ventrolateral body plates; suborbital shelf convex, obscuring eye from ventral view; deep pits on dorsal surface of head and within interorbital depression absent. Orbit with small scales. |
| 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 | 22 - 22 |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | 0 - 0 |
| Soft-rays total | 5 - 5 |
| Adipose fin | absent |
| Attributes | more or less truncate; more or less normal |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 5 - 5 |
| Pectoral | Attributes transformed to 'aerofoils' |
| Spines 0 | |
| Soft-rays 15 - 19 | |
| Pelvics | Attributes other (see diagnosis) |
| Position thoracic before origin of D1 | |
| Spines 1 | |
| Soft-rays 3 - 3 |