Gen. Sp. Orchid. Asclep.  (1829) t. 
Monopodial epiphytes. Stem short or elongated. Leaves few to many, arranged in two rows, sheathing at the base, glabrous, deciduous, duplicate, leathery. Inflorescence lateral, a raceme or a panicle. Flowers small, resupinate or not. Sepals free. Petals free, usually rather similar to the dorsal sepal, but sometimes much narrower. Lip adnate to the column, spurred, back wall of the spur provided with an erect, glabrous lamella. Column-foot absent. Pollinia 4, more or less unequal, arranged in two bodies, solid, caudicles absent, stipe present, viscidium present.
Tropical Asia, Malaysia, Indonesia, the Philippines, Papua New Guinea, Australia, east to Samoa. About 35 species; in New Guinea 3 species.
Epiphytes in lowland forests, also on isolated trees.
A relative of Cleisostoma with small, mostly dull-coloured flowers, characterised by the lip that consists largely of the spur, and in which an erect lamella can always be found inside the spur. Most species are not very attractive, as a result they are collected more by accident than on purpose, the plants being similar to those of related monopodial genera with more showy flowers.