| a tan, striped, snail-eating perch, Percina tanasi, 3 in. (7.5 cm) long, occurring only in the Tennessee River: a threatened species. |

| snail darter n. A small snail-eating darter (Percina tanasi) that formerly was found only in the Little Tennessee River. It was thought to have become extinct after construction of a dam, but later was discovered in several other Tennessee streams. |