; superorder Protacanthopterygii, order Salmoniformes)
A small family of freshwater fish that have relatively short, stout bodies. The soft-rayed, single, dorsal and anal fins are placed well back on the body, near the somewhat rounded tail fin. The small pelvics are found just anterior to the anal fin. Capable of surviving harsh conditions (e.g. low oxygen concentration and low water temperature), mud minnows have an interesting distribution: USA, Alaska, Siberia, and eastern Europe. There are about five species.
Subjects: Zoology and Animal Sciences.