| Main Ref. | Bass, A.J., 1986 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral | fusiform / normal |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | placoid scales |
| Diagnosis |
Pectoral fins about as long as head or longer, relatively broad-tipped in young and adults; snout usually narrowly to bluntly pointed, usually not acute; cusps of upper and lower anterior teeth straighter, with tips not reversed (Ref. 43278). Caudal fin lunate, with a very long lower lobe (Ref. 13574). Dark blue above, white below, with dusky markings on underside of snout, around mouth (Ref. 6581). |
| Ease of Identification | likely to be confused with closely related species. |
| 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 | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| total |
| Attributes | |
| Fins number | 2 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 0 - 0 |
| Soft-rays total | 0 - 0 |
| Adipose fin | absent |
| Attributes | other (see remark); asymmetric |
| Fins number | 1 |
| Spines total | 0 - 0 |
| Soft-rays total | 0 - 0 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 0 - 0 | |
| Pelvics | Attributes more or less normal |
| Position abdominal behind origin of D1 | |
| Spines 0 | |
| Soft-rays 0 - 0 |