Dorsal soft rays (total): 11; Analsoft rays: 31 - 35; Vertebrae: 37 - 38
9.3 cm SL (male/unsexed; (Ref. 75890))
Both Acestrocephalus nigrifasciatus and Acestrocephalus sardina have the same color pattern and eye size, distinct from all their congeners. In addition, Acestrocephalus nigrifasciatus has more scale rows above (13-14 vs. 10-12) and below (12-13 vs. 10-12) lateral line. Differs from Acestrocephalus sardina by having longer and narrower muscular hiatus of the pseudotympanum than that of Acestrocephalus sardina; and the fibers of the obliquus inferioris muscle are not visible as in the latter species (Ref. 75890).Description: Dorsal fin ii,9; Anal fin iv,27-31; Pectoral fin i+14-15; Pelvic fin i+7 (Ref. 75890).