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In scaled reptiles, the ocular scales are those forming the margin of the eye. The name originates from oculus which is Latin for "eye" and, in the broadest sense, refers to a scale associated with the eye. The numbers of these scales present, and sometimes the shapes and sizes, are some of many characteristics used to differentiate species from one another.
- Preocular scales, or preoculars, are those lying directly in front of and in contact with the eye.
- Postocular scales, or postoculars, are those lying directly behind and in contact with the eye.
- Supraocular scales, or supraoculars, are enlarged scales on the crown immediately above the eye.
- Subocular scales, or suboculars, are those lying directly below and in contact with the eye.
Collectively these scales are referred to as circumorbital scales, circumorbitals, or a circumorbital ring.
Occasionally, the term ocular scale is used without a prefix, in which case it specifically refers to the brille, also known as the spectacle: or eyecap. This is a transparent scale that covers and protects the eye. It is formed in embryonic snakes when the transparent upper and lower eyelids fuse together. Once hatched, a snake does not possess eyelids and the brille carries out some of these functions.
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