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In scaled reptiles, supraocular scales are (enlarged) scales on the crown immediately above the eye. The size and shape of these scales are among the many characteristics used to differentiate species from each another.
In many species of boids and viperids, the supraoculars are heavily fragmented. In others, such as the colubrids and elapids, they are enlarged.
Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. 359 pp. ISBN0-89464-877-2.