| 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 tehuacanensis is distinguished from other congenes in central Mexico by the following characters: rays on anal fin, mean fewer than 24 (vs. mean 24 or more in A. aeneus); total gill rakers, mean fewer than 20 (vs. mean 22 or more in A. finitimus); head shorter, mean 21.9% SL (vs. mean 23.8% or more); snout shorter, mean 3.3% SL (vs mean 4.2% or more); interorbital, mean 8% SL (mean 9-10% SL in A. acatlanensis and A. mexicanus); pectoral fin shorter, mean 19.3% SL (vs. mean ca. 21% in A. acatlanensis and A. mexicanus); anterior fontanel longer (vs. shorter); infraorbital II, triangular with an angled base (vs. base convex in A. acatlanensis, A. aeneus and A. mexicanus); epibranchial III, distal segment straight (vs. curved in A. finitimus and A. mexicanus); first dorsal pterygiophore, dorsal edge angled (vs. curved in A. mexicanus) (Ref. 118583). |
| Ease of Identification |
| Lateral Lines | Interrupted: No |
| Scales on lateral line | 32 - 36 |
| Pored lateral line scales | |
| Scales in lateral series | |
| Scale rows above lateral line | 7 - 8.5 |
| Scale rows below lateral line | |
| Scales around caudal peduncle | 15 - 17 |
| Barbels | |
| Gill clefts (sharks/rays only) | |
| Gill rakers | |
| on lower limb | |
| on upper limb | |
| total | |
| Vertebrae | |
| preanal | |
| total | 32 - 33 |
| Attributes | no striking attributes |
| Fins number | 1 |
| Finlets No. | Dorsal |
| Ventral | |
| Spines total | |
| Soft-rays total | 9 - 9 |
| Adipose fin | present |
| Attributes | forked |
| Fins number | |
| Spines total | |
| Soft-rays total | 18 - 23 |
| Pectoral | Attributes more or less normal |
| Spines | |
| Soft-rays 13 - 14 | |
| Pelvics | Attributes more or less normal |
| Position abdominal before origin of D1 | |
| Spines | |
| Soft-rays |