| Main Ref. | Bifi, A.G., C.S. Pavanelli and C.H. Zawadzki, 2009 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| Striking features | |
| Body shape lateral | elongated |
| Cross section | |
| Dorsal head profile | |
| Type of eyes | |
| Type of mouth/snout | |
| Position of mouth | |
| Type of scales | |
| Diagnosis |
This species differs from its congeners inhabiting the Río de La Plata and coastal basins of southern Brazil, except A. agostinhoi, A. multispinis, A. mullerae, A. taunayi and A. formoso, by possessing a maxillary barbel shorter and not free from its lower lip (vs. longer and free from lower lip); from the first 4 species, by the width of mandibulary teeth row 13.4-15.5% of HL (vs. 15.8-19.3%, 15.5-19.4%, 16.5-21.0% and 15.8-23.1%, respectively) and 32.9-37.9% of interorbital width (vs. 38.4-53.6%, 40.7-53.8%, 39.3-58.0% and 39.4-51.4%, respectively); from A. formoso by orbital diameter 11.9-15.3% of HL (vs. 8.3-8.7%), caudal peduncle depth 9.0-10.9% of SL (vs. 7.8-8.7%) and number of dentary teeth 40-68 (vs. 110) (Ref. 83296). |
| 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 | |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| total |
| Attributes | |
| Fins number | |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | 1 - 1 |
| Soft-rays total | 7 - 7 |
| Adipose fin |
| Attributes |
| Fins number | |
| Spines total | 1 - 1 |
| Soft-rays total | 3 - 4 |
| Pectoral | Attributes |
| Spines | |
| Soft-rays 16 - 16 | |
| Pelvics | Attributes |
| Position | |
| Spines 1 | |
| Soft-rays 5 - 5 |