Satan eurystomus

Satan is a genus of catfish of the family Ictaluridae. Commonly known as the "Wide-mouth blind cat", Satan eurystomus Hubbs, Bailey, 1947 was first found inhabiting a well, and is adapted for a light-less, subterranean environment. They are known only from subterranean streams more than 1/4 mile below ground and five artesian wells around San Antonio, Texas.

The genus is most closely related to the Flathead Catfishes of the genus Pylodictis.