Genus Arthrochilus

Arthrochilus F. Muell.,
Fragm. 1 (1858) 42

Terrestrial plants with subterranean tubers. Leaves few, rosulate, sheathing at the base, glabrous, dorso-ventrally flattened, not articulate, convolute, herbaceous. Inflorescence terminal, a raceme, often flowering before the leaves appear. Flowers rather small, not resupinate. Sepals free. Petals free, narrow, shorter than the dorsal sepal. Lip without spur, clawed, the blade hammer-shaped, mobile, hairy. Column-foot present. Pollinia 4, mealy, caudicles absent, stipe absent, viscidium absent.

Australia, New Guinea. About 4 species; in New Guinea 2 species.

Terrestrial in seasonally wet open places in savanna woodland.

Arthrochilus is closely related to the bizarre Australian genus Drakaea, in which it has been included in the past. From other terrestrial orchids in New Guinea it is readily distinguished by the hinged insect-like apical part of the lip. Two species seem to occur in New Guinea, but they have each been found only once. Both have been found conspecific with previously known Australian species, but some botanists (e.g. M. A. Clements) are not convinced this is correct.