Genus Hymenorchis

Hymenorchis Schltr.,
Repert. Spec. Nov. Regni Veg. Beih. 1 (1913) 994

Monopodial epiphytic plants. Stem elongated. Leaves 4-many, sheathing at the base, glabrous, dorso-ventrally flattened, articulate, duplicate, leathery; sheaths and blade with serrate margins. Inflorescence lateral, a raceme. Flowers small, resupinate, pale green or whitish, usually with a deeper green lip. Sepals free, margins usually serrate. Petals free, intermediate in shape between the lateral sepals and the dorsal sepal. Lip adnate to the column, spurred, not mobile. Column-foot absent. Pollinia 2, solid-waxy, caudicles absent, stipe present, viscidium present.

Java, Philippines, New Guinea, New Caledonia; about 8 species.

Distribution in the Philippines
Luzon (Mt. Province, Ifugao, Benguet, Nueva Ecija, Nueva Vizcaya); 1 species [Hymenorchis vanoverberghii (Ames) Garay].

Epiphyte in montane forest.

These small monopodial orchids are quite distinctive on account of the toothy leaf margins, while the greenish-white flowers are relatively large for the size of the plant. The genus has its centre of diversity in New Guinea. The Philippine endemic genus Ceratocentron appears to be closely related to Hymenorchis.