any of numerous fishes constituting the family Stichaeidae (order Perciformes). All of the approximately 60 species are marine, and most are restricted to the northern Pacific Ocean; a few species occur in the North Atlantic. Members of the family are characteristically elongate, with a low dorsal fin running the length of the body. In most species the pelvic fins are reduced or absent, a typical feature of the blennies, a group of fishes to which pricklebacks belong. They get their name from the presence of spiny rays that compose the dorsal fin.
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