Diagnostic Description
provided by Fishbase
Astyanax bacalarensis is distinguished from its congeners in the Yucatan by the following characters: anal fin origin never overlapping last dorsal-fin ray (always overlapping in A. altior); head length 28% SL or less (27% or more in A. altior); predorsal length, mean 50.4% SL (mean 53% or more in A. altior and A. angustifrons); mean distance between origins of pelvic and anal fins, 20.5% SL (vs. mean 19.3% or less); humeral spot rectangular-triangular to oval (P-shaped to indistinct in A. belizianus and A. brevimanus) (Ref. 118583).
Morphology
provided by Fishbase
Dorsal soft rays (total): 9 - 11; Analsoft rays: 21 - 27; Vertebrae: 32 - 33
