In snakes, the canthals are the scales along the upper surface of the canthus rostralis.
They are located behind the level of the prenasal/postnasal suture and before the supraocular.
[1] They are also described as being located along the edge of the crown between the internasals and the supraoculars.
[2] If these are large scales that contact each other along the midline, they are more properly referred to as prefrontals.
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