Although Cymatium exile will not be confused with C gutturnium or most related species, it is similar to some forms of C moniliferum (A. Adams & Reeve).Cymatium exile is a very constant species; adult specimens have the smallest whorls and relatively longest anterior canals of any C. (Ranularia) species. The spire is very short. The periphery bears relatively few (four or five in each intervariceal space of most speci¬mens) large, sharply angled, widely spaced nodules. The inner lip is only weakly thickened, and bears 12 to 14 wide, prominent, closely spaced plicae over its whole surface. The interior of the outer lip is also coarsely plicate. The aperture and most of the exterior are consistently white or cream, with bold, highly varied, bright red-brown splashes on the sutural ramp, in a zone around the base and upper part of the anterior canal, and on the varices. It is easily distinguished from coarsely nodulous specimens of G moniliferum by its much paler exterior with much brighter colour splashes, its thin, low inner lip (rather than the thick, wide, inner lip collar of C moniliferum), and its much more coarsely plicate inner lip.
All specimens of C. exile I have examined come from either the Philippine Islands or the Red Sea.