Distribution: Atlantic and Pacific Oceans. Flat, batoid-like body, wing-like pectoral fins with front margins overlapping gill slits but not attaching to head. Mouth and nostrils terminal, barbels on anterior margin. Eyes and large spiracles dorsal. Five gill slits partly on sides of head and partly on ventral surface. Two small spineless dorsal fins behind pelvic fins, anal fin absent. Caudal fin unique with lower lobe slightly longer than upper lobe (=hypocercal). Maximum length up to 2 m. They feed on a variety of small bony fishes, crustaceans, cephalopods, gastropods and bivalves. They use their highly protrusible, traplike jaws to suddenly snap up prey at high speed (Ref. 31369, 48821). Ovoviviparous, embryos feed solely on yolk (Ref. 50449).
Note: Families with unknown counts of dorsal or anal spines are also included