Oaxaca Cave Sleeper is a newly discovered species

This Oaxaca Cave Sleeper is one of thirteen specimens collected from a cave beneath a reservoir on Mexico's Tonto River. It lacks eyes, is unpigmented, and has sensory adaptations characteristic of fish that live in total darkness. Thuis is the holotype, the example used to describe and name this newly identified species. Credit: Howard L. Jelks and Stephen J. Walsh, USGS