Pike-Blennies, Tube-Blennies, and Flagblennies

The blennioid family Chaenopsidae includes the pike-blennies, tube-blennies, and flagblennies, all percomorph marine fish in the order Blenniiformes. The family is strictly tropical, ranging from North to South America. Members are also present in waters off Japan, Taiwan and Korea. Fourteen genera and 91 species are represented, the largest being the sarcastic fringehead, Neoclinus blanchardi, at 30 cm (12 in) in length; most are much smaller, and the group includes perhaps the smallest of all vertebrates, Acanthemblemaria paula, measuring just 1.3 cm (0.51 in) long as an adult.

With highly compressed bodies, some may be so elongated as to appear eel-like; chaenopsids are scaleless and lack lateral lines. Their heads are rough and may be armed with spines. There may be 17 to 28 spines in the dorsal fin, with two in the anal fin.