climbing perch, (Anabas testudineus), small Asian freshwater fish of the family Anabantidae (order Perciformes) noted for its ability to live and walk about out of water. The climbing perch is an air-breathing labyrinth fish. Rather oblong, brownish or green, it grows to about 25 cm (10 inches). It lives in ponds and ditches and sometimes emerges for short periods, “walking” with a jerky motion, aided by its tail and by spines on the lower edges of its gill covers. See also labyrinth fish.