Distinguished by the following characteristics: adult females and juveniles are generally brownish grey with dark vermiculations; camouflage phase has 5 dark brown saddles separated by short white bars below the dorsal fin; large males sometimes display a "black-belly" and "black-back" phase; black-belly phase is mostly pale grey, with faint dark reticulations below soft dorsal fin, belly and ventral part of the body above anal fin black, as are margin of the soft dorsal fin, central rear part of caudal fin and rear margins of pectoral and pelvic fins; depth of body contained 3.0-3.5 times in SL; head length 2.5-2.7 times in SL; convex interorbital area; angle of preopercle produced into a rounded lobe bearing enlarged serrae; posterior nostrils of adults much larger than anterior ones; smooth lateral body scales, except those covering pectoral fin (Ref. 89707).