Family Congridae

Diagnosis. Medium to large size. Body moderately elongate to elongate, round in cross section anteriorly, compressed posteriorly; anus usually located at anterior one-half to one-third TL; tail variable in form, from blunt to slender. Snout variable in form, from long and slender to short and pug-nosed. Mouth variable, gape usually ending below eye; upper jaw usually longer than lower, occasionally jaws equal, and rarely lower jaw longer. Eye well developed. Anterior nostril tubular, near tip of snout; posterior nostril usually on side of head in front of eye, rarely above eye or on upper lip; flange on upper and lower lip present or absent. Teeth variable, from small and granular to long and fang-like. Gill opening usually a crescentic slit just in front of pectoral fin. Dorsal and anal fins present, confluent around tip of tail; dorsal-fin origin closer to pectoral fin than to anus. Pectoral fin usually present and well developed. Lateral line complete. Scales absent.