At maximum, the Sharp-tailed Snake may grow to a length of 19 inches (47.5cm), but most adults are about 12 inches (30cm) long. Shiny reddish-brown or gray scales above and a whitish line down the side characterize Contia tenuis. An alternating pattern of black, pale greenish, gray, or cream bars can be found on its belly, and its smooth scales come in 15 rows around the body. The most distinguishing characteristic of this snake is the sharp spine-like scale at the tip of its tail. Although the function of this scale is not completely understood, it is thought to be used as an anchor during struggles with its victims (Basey 1976; Leviton 1971).