Bijdr. (1825) 342
Sympodial epiphytes, occasionally terrestrial in open shrubby vegetation, with very short, rarely elongated rhizomes. Stem usually much elongated, rarely short, not fleshy. Leaves usually many, rarely few, sheathing at the base, arranged in two rows, hairy at least on the sheaths, deciduous, duplicate, thin-leathery. Inflorescence lateral, a few to several-flowered raceme. Flowers small to medium-sized, resupinate. Sepals free, hairy outside. Petals free, almost always much narrower than the sepals. Lip without spur, not mobile. Column-foot present. Pollinia 8, solid, caudicles present, stipe absent, viscidium absent.
Nepal, Southeast Asia, Malaysia, Indonesia, the Philippines, Papua New Guinea, Pacific islands, east to Vanuatu. About 50 species; in New Guinea c. 25 species.
Epiphytes in lowland and montane forest, sometimes terrestrial in open shrubby vegetation.
Species of Trichotosia are slender-stemmed plants that are easily recognised by the more or less conspicuous covering of yellow or red-brown hairs on the leaf-sheaths and usually also on the leaves and the inflorescences. Some Dendrobium species may possess hairy leaf sheaths, but these hairs are blackish or white, never red-brown or yellow. Trichotosia is not often cultivated, although they are easy subjects to grow. New Guinea may be regarded as one of the main centres of diversity for this genus.