Although the anatomy of the gastrointestinal tract has been characterized in the lowland tapir (Tapirus terrestris), the exact anatomy of its tongue has not been studied. Samples of the lingual papillae and lingual glands were collected from the tongue of an adult female lowland tapir. The microscopic analysis of the structure of the lingual papillae and the histochemical analysis of the secretion of the lingual glands were analyzed. The tongue of the tapir is divided into the apex, body with a distinct lingual prominence, and the root. Its ventral surface is smooth. The most numerous of the mechanical papillae were the filiform papillae, while numerous conical papillae with a sharp apex or more rounded papillae were present in the root of the tongue. There were also nine vallate papillae and pair of foliate papillae. The foliate papillae contained several folds parted by 12-14 grooves. The mucous secretion produced by the lingual glands was more obvious than the serous secretion. The features of the dorsal surface of the tongue as well as the shape and number of the lingual papillae on the surface of the tongue of the examined female tapir differ compared to Equidae or Rhinocerotidae, the other two representatives of Perissodactyla. However, further study is necessary for the synapomorpy of the tapir's tongue.

Department of Anatomy Histology and Embryology Faculty of Veterinary Medicine University of Veterinary and Pharmaceutical Sciences Brno 61242 Brno Czech Republic

Department of Biostructure and Animal Physiology Faculty of Veterinary Medicine Wrocław University of Environmental and Life Sciences 51 361 Wrocław Poland

Department of Morphological Sciences Faculty of Veterinary Medicine Warsaw University of Life Sciences 02 776 Warsaw Poland

Department of Physiology Faculty of Veterinary Medicine University of Veterinary and Pharmaceutical Sciences Brno 61242 Brno Czech Republic

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