(Family):Cross section of caudal peduncle square. Two fleshy keels on both sides of caudal base. Dorsal fin divided distinctively into spinous and soft portions. This genus only. (Species):Body low, depth less than 30% of body length. Scales large, lateral-line scales about 40. Scaled area on head not exceeding to anterior eye margin. Body color black dorsally, silvery white ventrally. No markings on sides.
Distribution:
Distributing widely in western Central Atlantic, from Maine to Uruguay.
Remarks:
A similar fish known in this area A. melanum has small scales, more than 60 lateral-line scales, and cephalic scaled area exceeding to anterior margin of eye. (Shimizu)