Scanning electron microscopic study on the tongue in the scarlet macaw (Ara macao)

The dorsal lingual surface of scarlet macaw (Ara macao) was examined by scanning electron microscopy. Macroscopically, the lingual apex of the scarlet macaw had a lip-like shape. Three parts were distinguished in the dorsal surface of the tongue: the apex, body, and root of the tongue. The surface of the lingual apex had many grooves toward lingual root. The surface of the lingual apex was relatively smooth. The central surface of the papillary layer in the lingual apex after removal of the epithelium consisted of numerous dermal papillae, but the papillae were not observed in the lateral region. A pair of openings of the lingual glands was observed in the posterolateral region of the lingual body. The opening of the lingual gland after removal of the epithelium showed more clear structure than before removal. Many conical papillae in the posterior region of the lingual body were observed. The structure of the tongue of the scarlet macaw was different from that of the rainbow lorikeet.