Astyanax aeneus

(Günther 1860)

Astyanax aeneus
The skull of epigean (a) and troglomoprphic (b) Astyanax aeneus (from Espinasa et al. 2001)


Espinasa, Rivas-Manzana and Espinosa Perez (2001) describe a stygobitic, hypogean population from Mexico and the following details relate only to the hypogean animals.






No details are provided by Espinasa, Rivas-Manzana and Espinosa Perez (2001).


Known only from the “type locality” of the hypogean animals: Gruta de las Granadas, north-east of Taxco, Guerrero, southern México (18o34’30”N, 99o33’7”W). The stream flowing from the cave is a tributary of the Amacuzac River.


The collection site is a cave passage 180m long to a sump pool. The cave is a resurgence and water flows out of it all year round. Within the cave there is a mixed population of the stygomorphic, presumably stygobitic, animals and ordinary surface animals. Only about 10% of the population are stygomorphic. This suggests that their true habitat is undiscovered and lies further into the cave.


From the few data available it appears that the stygomorphic animal is a separate taxon from the epigean animals and that it is currently hybridising at the collection site. This situation is analogous to that of Astyanax jordani in La Cueva Chica (Breder 1942) and perhaps Poecilia mexicana and Rhamdia quelen urichi at their only known sites. Should this turn out to be the case a new name would be appropriate to differentiate the taxon.

Conservation Status


The hypogean population of this species is currently known from only one site and is therefore VU D2 at least.

Museum Holdings

None known.

Key References

Espinasa, L., Rivas-Manzano, P. and Perez, H.E. Journal Article 2001 A new blind cave fish population of genus Astyanax: Geography, morphology and behaviour
Espinasa, L Journal Article 2011 Promoting undergraduate research in large classrooms: Guerrero cave Astyanax - Old or young colonisation?
Esquivel-Bobadilla, S Thesis 2011 Análisis genético de Astyanax mexicanus (Characidae, Teleostei, Pisces) de la vertiente atlántica de México usando microsatélites.
Pazza, R Journal Article 2013 Molecular systematics of the genus Astyanax - Starter edition
Silva, D. M. Z. A., Utsunomia, R., Pansonato-Alves, J.C., Oliveira, C. and Foresti, F. Journal Article 2015 Chromosomal Mapping of Repetitive DNA Sequences in Five Species of Astyanax (Characiformes, Characidae) Reveals Independent Location of U1 and U2 snRNA Sites and Association of U1 snRNA and 5S rDNA
Schmitter-Soto, JJ Journal Article 2016 A phylogeny of Astyanax (Characiformes: Characidae) in Central and North America
Schmitter-Soto, JJ Journal Article 2017 A revision of Astyanax (Characiformes: Characidae) in Central and North America, with the description of nine new species
Elliott, W.R. Book 2018 The Astyanax Caves of Mexico: Cavefishes of San Luís Potosí, Tamaulipas, and Guerrero
Pazza, R., Dergam, J.A. and Kavalco, K.F. Journal Article 2018 Trends in karyotype evolution in Astyanax (Teleostei, Characiformes, Characidae): Insights from molecular data.
Levels of eye development in the Granadas cave population: a – eyeless, b – sunken eye, c – reduced pupil, d – eyed. Pictures c and d are of the same animal and show asymmetrical development. From Espinasa et al. (2001)