Pipistrelle bat tongue. Coloured scanning electron micrograph (SEM) of the surface of a pipistrelle bat's (Pipistrellus pipistrellus) tongue showing three types of papillae (projections). Covering the majority of the tongue's surface are scale- like papillae. These and the posterior-median papillae at top left are mechanical papillae; they sense pressure. The round red areas are fungiform papillae, which contain the taste buds.