The Mexican mole lizard is a pink, lizard-like reptile that ranges in length between 18 to 24 cm, but doesn't live very long - a longevity of one to two years. Their skin is closely segmented to give a corrugated appearance, and like earthworms, their underground movement is by peristalsis of the segments. The forelegs are strong and paddle-like, while the hindlegs have disappeared, leaving behind only vestigial bones visible in X-rays.

The Mexican tetra (Astyanax mexicanus) is a blind, freshwater cave fish native to central and eastern parts of Mexico. Growing to a maximum total length of 12 cm (4.7 in), this species is notable for having no eyes or pigment; it has a pinkish-white color to its body (resembling an albino).

The Mexican tetra spends most of its time in midlevel water above the rocky and sandy bottoms of pools and backwaters of creeks and rivers of its native environment. Coming from a subtropical climate, it prefers water with 6.5–8 pH and a temperature range of 20 to 25 °C (68 to 77 °F). In the winter, some populations migrates to warmer waters. Its natural diet consists of crustaceans, insects, and annelids.

Given their peaceful nature, this species is popu ...