Sicyopterus rapa Parenti & Maciolek 1996

Distinguished from congeners by a low number (approximately 45) of teeth on each premaxilla, and ventral body surface unscaled in largest adults; interspinal membrane or frenum thick; branched caudal-fin rays 13-15; vertebrae 10+16=26; no rakers on first gill arch; transverse scales 44-62 rows; unscaled dorsal surface of head; operculum, cheeks and lateral portion of body to first dorsal fin irregularly scaled with small cycloid scales; ventral surface of body unscaled in largest adults, otherwise incompletely covered with small cycloid scales; remainder of body to caudal peduncle covered with imbricate ctenoid scales; anterior portion of caudal fin rays with smaller ctenoid or cycloid scales in one or two discrete rows dorsal and ventral to each ray (Ref. 12759).

Dorsal spines (total): 7; Dorsal soft rays (total): 11; Analspines: 1; Analsoft rays: 10