The Palatal Dentition in Squamate Reptiles: Morphology, Development, Attachment, and Replacement

Abstract

Abstract The palatal dentition in squamate reptiles is poorly known compared to the marginal dentition. We surveyed species representing all squamate families for the occurrence of palatal teeth. For those exhibiting palatal teeth, we investigated palatal tooth arrangement, morphology, development, attachment, and replacement patterns using SEM, high-resolution X-ray computed tomography imaging, and histology. We found substantial variability in the presence of palatal teeth and in the arrangement and number of palatal tooth rows at familial, generic, and specific levels among nonophidian lizards. However, snakes exhibit much more uniformity in both these respects. These patterns of variability have implications for trade-offs between phylogenetic, functional, and developmental constraints. When numerous, palatal teeth in most nonophidian lizards are either arranged in fields or loosely organized rows near the back of the oral cavity. In contrast, palatal teeth in snakes and in the “lizards” Shinisaurus a...