| Main Ref. | Costa, W.J.E.M., 2007 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral (shape guide) | elongated |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | cycloid scales |
| Diagnosis |
Diagnosed from all other congeners of the subgenus Melanorivulus in possessing 2+1 mandibular neuromasts. Differs from all species of Melanorivulus, except Rivulus violaceus by its caudal peduncle in both sexes with dark purplish gray spots and humeral region in males with a bright greenish blue blotch. Can be separated from Rivulus violaceus by having fewer dorsal-fin rays 8-9 (vs. 10-11) and fewer anal-fin rays 11-13 (vs. 14-15). Additional characters helpful in the identification of this species include: scales in the longitudinal series 30-31; flank with close red dots, arranged in chevron-like series with the vertex on the mid-lateral line; and caudal fin in males with red bars (Ref. 76975). |
| 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 | 16 - 16 |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | 9 - 9 |
| Vertebrae | |
| preanal | |
| total | 30 - 30 |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | |
| Soft-rays total | 8 - 9 |
| Adipose fin | absent |
| Attributes | more or less truncate |
| Fins number | |
| Spines total | |
| Soft-rays total | 12 - 13 |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays 13 - 13 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays 7 - 7 |