| Main Ref. | Schmitter-Soto, J.J., 2017 |
| Appearance refers to | |
| Bones in OsteoBase |
| Specialized organs | |
| Different appearance | |
| Different colors | |
| Remarks |
| 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 |
Astyanax tamiahua is distinguished from other congeners in Veracruz and northern Mexico by the following characters: body deeper, mean 35.9% SL (vs. mean 33.9% SL in A. argentatus); head length, more than 26% SL (vs. 26% or less in A. acatlanensis, A. argentatus and A. rioverde); in lateral view, supraoccipital slightly concave (vs. angled in A. finitimus); infraorbital II, triangular with an angled base (vs. with a long convex base in A. argentatus and A. mexicanus); first dorsal pterygiophore, rostral edge angled (vs. curved in A. argentatus and A. mexicanus) (Ref. 118583). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | 30 - 34 |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | 7 - 7 |
| Scale rows below lateral line | |
| Scales around caudal peduncle | 15 - 18 |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | 11 - 12 |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| 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 | 20 - 25 |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays 10 - 11 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays |