In snakes, the supraoculars are usually enlarged scales located on the crown over each eye. In some species, such as Atropoides nummifer and A. picadoi, these scales may be either divided into many smaller scales or reduced to small elongated scales. In others, such as Ophryacus undulatus and O. melanurum, the supraoculars are fragmented into many smaller scales, one or more of which may form a spine or hornlike structure above the eye.
- Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. ISBN 0-8014-4141-2.