The study describes the ultrastructure of the tongue in the Patagonian mara (Dolichotis patagonum) using light and scanning electron microscopy. Histochemical methods were used for evaluation of lingual salivary glands. The tongue is divided into a small and rounded apex, a narrow corpus, and a significantly wider radix, with a well-developed lingual prominence. The tip of the apex is free of papillae. The caudal part of the apex and the corpus are covered by filiform papillae. Round fungiform papillae are scattered among them. Papillae on the narrow stalk are conical. The radix contains caudally bent papillae forming wide flat prominences, slender, hook shaped filiform papillae, foliate papillae, and two oval vallate papillae. Taste buds were found on the lateral sides of the foliate and vallate papillae. Purely serous salivary glands are beneath the vallate and foliate papillae. Serous acini and mucous tubules are in the lingual radix. The Patagonian mara is the only hystricomorph rodent with described hyaline cartilage strengthening the lingual radix. Some typical signs of adaptation to herbivorous diet were found. The structure of the tongue is adapted to grass-feeding, as grasses form the main component of their diet.

• Klíčová slova
• herbivorous diet, histochemistry, hystricomorph, lingual papillae, lingual prominence, salivary glands,
• Publikační typ
• časopisecké články MeSH

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.

• Klíčová slova
• Perissodactyla, Tapirus terrestris, adaptation to feeding, lingual glands, tongue,
• Publikační typ
• časopisecké články MeSH