Morphologically almost identical with S. octozona, but differs strikingly in coloration. Instead of 8-9 thin pale complete bands on a dark background, it has 7-12 thin dark mostly incomplete bands on a pale background. Most of the specimens have only 7-8 incomplete bands; only the 3.77 cm specimen from Huay Huang has 12 bands, many of which go completely around the body (as in S. octozona). Predorsal scales about 40 and transverse scale rows 19/1/14.