Diagnosis: pectoral-fin spine strongly denticulate posteriorly; barbels very short, inner mandibular barbels often rudimentary (Ref. 43912, 57127, 81643). Posterior nostrils as close as (Ref. 57127, 81643) or closer to each other than the anterior ones (Ref. 43912, 57127, 81643). 52-64 branched anal-fin rays; 10-16 gill rakers on lower limb of first gill arch; adipose fin always present (Ref. 43912, 57127, 81643).

Description: 9-11 brachiostegal rays on one side of head; caudal peduncle shorter than deep, as long as deep or slightly deeper than long; nasal barbel short and rarely reaches beyond posterior border of eye; maxillary barbel sometimes reaches beyond posterior border of eye but in general shorter; inner mandibular barbels often rudimentary, outer ones reach at least to posterior border of eye and at maximum to anterior border of opercle (Ref. 43912). A very peculiar species easily identified by the combination of the distinguishing characters mentioned above; it might be confused with S. mandibularis or S. multitaeniatus but it is easily distinguished from both by the pectoral spines with coarse serrations on their inner side and by the rudimentary inner mandibular barbels (Ref. 43912).

Coloration: no information available on colour pattern in life (Ref. 57127, 81643). Preserved specimens: head and back dark brown; traces of lateral bands visible, one above lateral line, another one at anal-fin base and a third along anal-fin margin; belly often spotted/speckled; base and margin of caudal fin greyish (Ref. 43912, 57127, 81643).