Megupsilon aporus

The Catarina pupfish was a diminutive species of fish in the family Cyprinodontidae, first described in 1972. It was endemic to a spring in Nuevo León, Mexico. In an attempt of saving the rapidly declining species, some were brought into captivity in the late 1980s and early 1990s, but it proved very difficult to maintain. In 1994 it became extinct in the wild. Gradually the captive populations also perished. The last male died in 2014, and the species became extinct.

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