Genus Allothunnus

A monotypic genus that is circumglobal in Southern Hemisphere waters.  Body elongate, robust; caudal peduncle with prominent lateral keel and smaller keel above and below on base of tail; mouth extending to below anterior half of eye; jaw teeth small, conical, 40–55 on side, fine teeth on palatines; modified elongate corselet of scales from pectoral-fin region along back to posterior end of 2nd dorsal fin, small scales behind and above lateral line, absent below; dorsal fins close together, 1st dorsal base about 3 times length of 2nd; 2nd dorsal and anal fins tall, pointed, almost opposite; caudal fin lunate; pectoral and ventral fins short, pointed; interpelvic process short and bifid.