Sulphur molly
The sulphur molly, locally known as molly del Teapa, is a critically endangered species of fish in the family Poeciliidae. It is endemic to Mexico, specifically to the Baños del Azufre near Teapa, Tabasco. The Baños del Azufre are sulfidic springs that contain high concentrations of toxic hydrogen sulfide. Poecilia sulphuraria has apparently evolved the ability to tolerate the toxic conditions. A few other Poecilia species are known from similar habitats in Mexico.
