Astyanax mexicanus

fish

Also known as: Anoptichthys jordani

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 18, 2026

Quick Summary

Astyanax mexicanus is a species of fish, previously known as Anoptichthys jordani, that is found in Mexico. This fish is characterized by its eyelessness and pale coloring, adaptations common to cave-dwelling species. It typically grows to about 7.5 cm (3 inches) in length and belongs to the characin family. While some cave fish are blind and pale, other cave-dwelling fish unrelated to Astyanax mexicanus have also evolved similar traits. This species is sometimes kept in home aquariums.1

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

cave fish
…of the best known is Astyanax mexicanus (previously Anoptichthys jordani), an eyeless, 7.5-cm characin (family Characidae) found in Mexico and often kept in home aquariums. The gobies in the genus Typhleotris inhabit karst caves in Madagascar. Others include Caecobarbus geertsi, an African member of the minnow family (Cyprinidae), and certain…
Read More
…of the best known is Astyanax mexicanus (previously Anoptichthys jordani), an eyeless, 7.5-cm characin (family Characidae) found in Mexico and often kept in home aquariums. The gobies in the genus Typhleotris inhabit karst caves in Madagascar. Others include Caecobarbus geertsi, an African member of the minnow family (Cyprinidae), and certain…
Read More