| Main Ref. | Malabarba, L.R. and F.C. Jerep, 2014 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks | Mature males have hooks on the pelvic and anal-fin rays. The hook bearing anal-fin rays are hypertrophied, expanded in the sagittal plane, and sometimes have fused ray segments. Adult males also have elongated last unbranched dorsal-fin ray and the first pelvic-fin ray, sometimes in a short filament. Mature males have hypertrophied ventral procurrent caudal-fin rays, and extend ventrally through the caudal peduncle muscles and skin (Ref 96959). |
| Striking features | |
| Body shape lateral | fusiform / normal |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | terminal |
| Type of scales | cycloid scales |
| Diagnosis |
Serrapinnus tocantinensis is distinguisged from its congeners by the elongation of the unbranched dorsal and pelvic-fin rays into filaments in mature males. It differs further from S. sterbai by the absence of a continuous mid-lateral black stripe extending from the opercular region to the caudal-peduncle spot. It can be separated from other congeners by having the following characters: 9 to 11 cusps in the premaxillary teeth (vs. 5 in S. microdon and S. potiguar, 7 in S. aster, 7 to 9 in S. calliurus, S. heterodon, S. kriegi, S. micropterus, S. notomelas and S. piaba and 10 to 12 in S. gracilis and S. littoris); dentary teeth without expanded cusps forming a sharp cutting edge (vs. dentary teeth with expanded cusps forming a sharp cutting edge in S. heterodon); hyaline dorsal fin (vs. with a proximal black blotch in S. notomela; and black spot absent on the posteroventral region of the abdomen (vs. present in S. kriegi) (Ref. 96959). Description: Dorsal-fin rays ii,8-9; anal-fin rays iii-iv,15- 21; pectoral-fin rays i,9-11; pelvic-fin rays i,6-7; scale rows between lateral line and pelvic-fin origin 4 or 5 (Ref. 96959). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | |
| Pored lateral line scales | 8 - 36 |
| Scales in lateral series | 31 - 36 |
| Scale rows above lateral line | 5 - 6 |
| 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 | 15 - 16 |
| total |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | 10 - 11 |
| Soft-rays total | |
| Adipose fin | present |
| Attributes | forked |
| Fins number | |
| Spines total | |
| Soft-rays total |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays 10 - 12 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays 7 - 8 |