tongue orchid

Dendrobium linguiforme is an epiphytic or lithophytic orchid with prostrate stems that produce wiry roots along almost their whole length. The roots are 1–4 cm (0.4–2 in) long and 3–4 mm (0.1–0.2 in) in diameter. There is a single leaf at the end of each branch of the stem. The leaf is oblong to egg-shaped, 2–4 cm (0.8–2 in) long and 8–15 mm (0.3–0.6 in) wide. It is 4–6 mm (0.16–0.24 in) thick and succulent with the upper surface smooth but with ridges and furrows. Up to twenty flowers are arranged in a raceme 5–15 cm (2–6 in) long. The dorsal sepal is linear to narrow lance-shaped, 15–22 mm (0.6–0.9 in) long and 3–4 mm (0.12–0.16 in) wide, the lateral sepals are 18–22 mm (0.7–0.9 in) long and 4–5 mm (0.16–0.20 in) wide, the petals slightly smaller. The petals and sepals are white to cream-coloured. The labellum is cream-coloured with pale purple markings and is 5–6 mm (0.20–0.24 in) long and 3–4 mm (0.12–0.16 in) wide. Flowering occurs in September and October.

Tongue orchid occurs in New South Wales and Queensland where it grows on rocks and trees, usually in sclerophyll forest and sometimes in rainforest or in rocky places. In New South Wales it occurs on the coast and tablelands north of Ulladulla and inland as far as Gungal and Tamworth. In Queensland it is found from the Atherton Tableland to Townsville and south from Gympie to the New South Wales border.