The front edges of the dorsal fins and the pectoral fins of "Syntontis" species are hardened into stiff spines. In "S. granulosus", the spine of the dorsal fin is long, about as long as the head, is almost completely straight, is smooth on the front and serrated on the back, and ends with short, black filament. The remaining portion of the dorsal fin is made up of seven to eight branching rays. The spine of the pectoral fin is slightly curved, almost as long as the dorsal fin spine, with small serrations on the front and large serrations on the back. The pectoral spine ends in short, black filament. The rest of the pectoral fins are made up of seven to eight branching rays. The adipose fin does not contain any rays, is long and well developed, and has a convex shape. The pelvic fin contains one unbranched and six to seven branched rays. The front edge of the pelvic fin is vertically forward of the front edge of the adipose fin. The anal fin contains three to five unbranched and seven to nine branched rays; it is vertically aligned with the adipose fin. The tail, or caudal fin, is forked, with pointed lobes, and contains eight rays on the upper lobe, nine rays on the lower lobe.