This species can be distinguished from its congeners through the following set of characters: body which is conspicuously robust and humped dorsally; second dorsal fin is upright and markedly tall (height 4.0%, 4.7%-5.3% TL); first and second dorsal-fin spines are elongated (first dorsal-fin spine length 4.3%, 3.3%-4.3% TL and second dorsal-fin spine length 4.4%, 3.9%-4.3% TL), and broad at base (first spine base length 0.9%, 0.7%-1.0% TL; second spine base length 1.0%, 0.8%-0.9% TL); caudal fin have a conspicuous rectangular dorsal lobe; the dermal denticles are tricuspid, markedly imbricate and broad at crown; differs from S. bahiensis by having a larger pectoral-fin anterior margin length, 15.9%, 15.5%-16.0% TL (vs. 14.3%, 14.4%-14.5% TL) and more elongate first dorsal-fin spine, its length 4.3%, 3.3%-4.3% TL (vs. 2.8%, 2.9%-3.0% TL), has a larger first dorsal fin with greater anterior margin length, 11.2%, 10.8%-11.4% TL (vs. 10.5%, 10.3%-10.6% TL) and fin base (length 8.2%, 7.7%-8.5% TL vs. 7.5%, 7.2%-7.3% TL, respectively); differs from S. lobularis by having a greater interdorsal distance, 26.4%, 24.0%-25.8% TL (vs. 22.3%, 21.9%-23.6% TL) (Ref. 109601).