| Main Ref. | Marinho, M.M.F., D.A. Bastos and N.A. Menezes, 2013 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | always different morphology between mature adults |
| Different colors | |
| Remarks | Presence of spines and hooks on fins only in males; tiny spines laterally located on unbranched dorsal-fin rays; hooks on all pelvic-fin rays and on last unbranched and first five or six branched anal-fin rays. Males have shallower body depth and longer pectoral and pelvic fins than females; and medial portion of pelvic bone of males expanded and dorsally projected (Ref. 94718). |
| Striking features | |
| Body shape lateral (shape guide) | fusiform / normal |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
This species differs from all members of the genus Tyttobrycon by the possession of tricuspid premaxillary teeth, tri- or pentacuspid maxillary teeth and four broad tricuspid anterior dentary teeth (vs. all teeth conical in the jaws). It can be further diagnosed from all congeners, except T. dorsimaculatus, by having 5-7 premaxillary teeth (vs. 8-9), and from T. dorsimaculatus by having only scattered melanophores on the dorsal fin (vs. dorsal fin with a conspicuous black spot). The presence of adipose fin separates this species from T. hamatus and T. spinosus (vs. adipose fin absent) (Ref. 94718). Description: Dorsal-fin rays ii,8-9; anal-fin rays iii-iv,12-14; pectoral-fin rays i,8-10; pelvic-fin rays i,7; 3 longitudinal scale rows below lateral line at pelvic-fin origin; 28- 31longitudinal scale row, including pored scales (Ref. 94718). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | 3 - 5 |
| Scales in lateral series | |
| Scale rows above lateral line | 4 - 4 |
| Scale rows below lateral line | |
| Scales around caudal peduncle | 12 - 12 |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | 13 - 14 |
| total | 31 - 33 |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | |
| Soft-rays total | 10 - 11 |
| Adipose fin | present |
| Attributes | forked |
| Fins number | |
| Spines total | |
| Soft-rays total |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays 9 - 11 | |
| Pelvics | Attributes more or less normal |
| Position abdominal behind origin of D1 | |
| Spines | |
| Soft-rays 8 - 8 |