Mammalian taste buds are widely distributed throughout the oral cavity pharynx and larynx. Most lingual taste buds are confined to the dorsal and lateral borders of the tongue and are associated with specialized structures called papilla. There are four main types of tongue papilla: the filiform, fungiform, circumvallate and foliate. The most numerous are the filiform, located over the anterior and posterior tongue dorsum, which do not contain taste buds and therefore have no gustatory function. The fungiform papillae contain one or more taste buds on their upper surface and are confined to the papillae. The circumvallate papillae are found at the oral and pharyngeal parts of the tongue. Taste buds are located on the sides of the papillae and sometimes in the wall surrounding the papillae. Humans have 8 to 12 circumvallate papillae arranged in a chevron.