Cuatro Cienegas softshell

The Cuatro Ciénegas softshell (Apalone spinifera atra), also called the black spiny softshell, is a subspecies of the spiny softshell turtle in the family Trionychidae. The subspecies, along with its parent species, was formerly classified in the genus "Trionyx".
Geographic range.
"A. s. atra" is found only in the Cuatro Ciénegas Basin in the state of Coahuila, Mexico.
Conservation status.
As of the last assessment in 1996, "A. s. atra" was considered "Critically Endangered" by the "IUCN Red List of Threatened Species".