Differs from A. nasutus and A. orthodus by its distinct humeral blotch and intermediate body depth. Sides and belly silvery over pearl white merging to a greenish brown back; in preserved specimens, a gray band runs from the humeral mark to the caudal peduncle which has a jet black rhomboidal mark extending to the tip of the middle caudal rays; transparent fins with minimal dark pigment; usually first rays of anal and sometimes dorsal and caudal fins with red or yellow pigment (Ref. 36880).