| Main Ref. | Russell, B.C., 1997 |
| Appearance refers to | Male; Female |
| 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 | fusiform / normal |
| 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 |
| Diagnosis |
Suborbital spine absent. Preopercle with 3 transverse scale rows. Pectoral fins long, reaching to or almost to level of origin of anal fin. Pelvic fins moderately long, reaching to or just beyond anus. Upper lobe of caudal fin produced into a short trailing filament. A line drawn upwards from the posterior edge of suborbital reaching the dorsal profile 2 to 5 scale rows before origin of dorsal fin. Axillary scale present. Color: Upper body pinkish, pearly white below. Compared to N. bathybius, this has a more or less straight caudal filament; is more slender and differs in color pattern: lower lateral stripe originates from above the pectoral-fin base; dorsal fin lacks undulating yellow lines; and upper caudal fin and filament red-edged. |
| Ease of Identification |
| Lateral Lines | 1 Interrupted: No |
| Scales on lateral line | 45 - 51 |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | 3.5 - 4.5 |
| Scale rows below lateral line | 9 - 12 |
| Scales around caudal peduncle | |
| Barbels | 0 |
| Gill clefts (sharks/rays only) | absent |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | 11 - 15 |
| Vertebrae | |
| preanal | |
| total |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal 0 - 0 |
| Ventral 0 - 0 | |
| Spines total | 10 - 10 |
| Soft-rays total | 9 - 9 |
| Adipose fin | absent |
| Attributes | forked; with dorsal filament |
| Fins number | 1 |
| Spines total | 3 - 3 |
| Soft-rays total | 7 - 7 |
| Pectoral | Attributes more or less normal |
| Spines 0 | |
| Soft-rays 15 - 17 | |
| Pelvics | Attributes more or less normal |
| Position thoracic behind origin of D1 | |
| Spines 1 | |
| Soft-rays 5 - 5 |