; class Pteraspidomorphi, order Myxiniformes)
A small family of marine, jawless fish (or fish-like vertebrates) that have an elongate and slender body, a cartilaginous skeleton, but no paired fins or scales. The slit-like mouth is surrounded by barbels and is supported by a powerful rasping tongue. There is considerable variation in the number of round gill openings. There are about 19 species, found in temperate to cold water.
Subjects: Zoology and Animal Sciences.