Poecilia sphenops, called the short-finned molly or common molly, is a poeciliid fish inhabiting freshwater streams, coastal brackish, and marine waters from Mexico to Colombia. The wild-type fishes are dull, silvery in color. The molly can produce fertile hybrids with many Poecilia species, most importantly the sailfin molly. The male mollies generally tend to be mildly aggressive.
Standard size of male fish is 3.2″ (8 cm) and female fish is 4.8″ (12 cm).