Light and Scanning Electron Microscope Studies of Lingual Papillae in Common Tree Shrew (Tupaia) and Variable Squirrel (Callosciurus finlaysoni) : A Comparative Study.

Abstract

The fine structure and distribution pattern of the lingual papillae of common tree shrew (Tupaia glis) and variable squirrel (Callosciurus finlaysoni) were comparatively investigated using scanning electron microscope and light microscope. The tongue of the common tree shrew had the same size and shape as that of the variable squirrel but consisted of three types of papillae: filiform, fungiform and circumvallate, instead of four types of papillae : filiform, fungiform, circumvallate and conical, as in the variable equirrel. The circumvallate papillae of both animals had the same number, size and position and located in an inverted triangle on the posterior portion of the tongue. Most of the fungiform papillae were found on the tip and lateral edge of the common tree shrew’s tongue, while there were no specific locations of their distribution in variable squirrel. However the shape of filiform papilla was totally different. It consisted of a basal circular budge and had 8-13 upper processes in the common tree shrew, while that of variable squirrel consisted of a basal flat plate like budge and had 4-6 upper processes.