Dorsal fins located fairly backward of body. Second dorsal distinctly larger than first dorsal (1.3〜1.6 times larger in base length). First dorsal originated somewhat posterior to rear end of pelvic base. Rear end of second dorsal slightly in advance of that of anal. Distance between pectoral and pelvic bases 11〜14 % of TL. Snout long, preoral length about 1/10 of TL, and somewhat longer than distance between dorsal bases. No enlarged denticle along upper margin of caudal fin. Eye large, about 2/5 of preoral length and somewhat smaller than internarial width. Labial folds prominent continuous around the corner of mouth. Teeth similar on jaws, mostly 5 cusped.
Distribution:
Gulf of Mexico to Guiana through Caribbean Sea.
Remarks:
Twenty-one species of the genus are known from the world. The present species and A. canutus are characterized by first dorsal smaller than the second, and first dorsal origin posterior to pelvic base. Trunk region of the latter is relatively short, so that the distance between pectoral and pelvic bases 6.0〜8.5 % of TL (Springer, 1979). (Uyeno and Sasaki)