This species is distinguished from all its congeners, except operculatum by the following characters: presence of the rounded blotches at the midlateral line as large as or

smaller than opercle (vs. rounded blotches larger than opercle or absent); differs from S. operculatum by having the maxillary barbel longer than half-length of the head (vs. shorter than half-length of head); tips of the pectoral-fin rays not extending beyond the interadial membrane (vs. extending beyond interadial membrane), skin flap in the posterior margin of the opercle rounded and short (vs. skin flap pointed and long); fleshy flap at the base of the maxillary barbel, thin, restricted to the maxilla and with distal margin rounded (vs. fleshy flap located anteriorly, thick, prolonged up to

the snout and with distal margin straight); caudal fin uniformly brown (vs. fin with a transversal black bar distally) (Ref. 122319).