Texas Blind Salamander

The species has a broad, flat snout and head, and vestigial eyes beneath that are covered by skin. This species' vestigial eyes contain an optic nerve, but are less developed than those of other species in the Eurycea, often lacking important features like lenses and well-defined retinas associated with image-forming vision. Similar to other cave-dwelling salamanders, this species has numerous neuromasts in their lateral line that detect mechanical stimuli in the environment. Many of these neuromasts express the PAX6 protein, which is often expressed during eye development of other salamander species. These neuromasts are thought to play an important role in navigation and prey detection for this species with reduced visual capacity. Like other neotenous salamanders, it has external gills for absorbing oxygen from the water. The salamander's mature length is around 13 cm (5 in). The forelimbs carry four digits and the hind limbs possess five digits. The species is found to be able to regenerate its tail and limbs if they are lost. Its diet varies by what flows into its cave, and includes blind shrimp (Palaemonetes antrorum), snails, and amphipods. It is not known if this salamander has any natural predators, however the stygobitic catfish Satan eurystomus also lives in Edwards Aquifer, so is a potential predator. …

Specimens have been collected at seven localities in the Purgatory Creek system and along the San Marcos Fault near San Marcos, Texas. Adults and immature larvae are well-adapted for living in underground streams or deep pools in caves, and many probably inhabit deep recesses that are not accessible to collectors. The deep pools are cool environments nearly constantly staying at 21–22 °C (70–72 °F) with a minimal current. It is a unique ground system hundreds of feet below Earth's surface. The first specimens of this species were collected in 1895 from a newly constructed well that drew water from 58 metres (190 ft) below the surface.