This species is distinguished by the following characters: head considerably broad (vs. slender in the S. haeckelii/besnardi group and S. hesperius); with brown saddles on a light brown background, predorsal saddles with anterior and posterior sharp median projections (vs. no projections in the S. haeckelii/besnardi group or S. hesperius) and light and dark, spiracle-sized or slightly smaller spots, no large white spots (vs. large white spots in S. hesperius); also, the snout is rounded and moderately short, preoral length 5% TL (vs. 4.5% TL in the S. haeckelii/besnardi group); preorbital length 6.4% TL and head length 20% TL (vs. 5% TL and 18% TL in S. hesperius); mouth width 9% TL (vs. 8% TL in the S. haeckelii/besnardi group and 7.2% TL in S. hesperius); pectoral-pelvic space 1.5 times pelvic-anal space (vs. equal in the S. haeckelii/besnardi group), and interdorsal space 2.3 times dorsal-caudal space (vs. 1.6 times in S. haeckelii/besnardi group); anal-fin base 8% TL (vs. 6.7% TL in S. hesperius, 8.3% TL in the S. haeckelii/besnardi group); cranium with flat basal plate, without keels; cranial width larger in females 42.7% NL (vs. 37.4% NL in S. haeckelii/besnardi group); with a terminal dermal cover in hindmost portion of clasper, covering terminal cartilages (none in S. hesperius); medium-sized, adult male at 44.5 cm TL and adult female 50.0 cm TL (vs. 35.3 cm and 41.0 cm, respectively, for the S. haeckelii/besnardi group) (Ref. 101269).