禾叶组 he ye zu

Grastidium Blume, Bijdr. 333. 1825.

Stems glossy, narrowly cylindric, rigid, leafy, continuing to lengthen for many years. Leaves grasslike (in Chinese species). Inflorescences axillary, emerging from a protective bract and piercing subtending sheath, appearing opposite next proximal leaf, new lateral inflorescence buds usually progressing distally, one at each node, allowing gregarious blooming at any season; a small but conspicuous pair of convex, indurate, laterally compressed sheaths penetrating enclosing sheath, shielding buds; each inflorescence flowering once, usually producing a pair of flowers. Flowers resupinate or not resupinate, ephemeral, stellate, usually facing one another, or sometimes in parallel or opposite directions. Sepals and petals often filiform. Mentum inconspicuous, decurved, conic. Lip 3-lobed or entire, ornamented with ridges that fragment distally into irregular calli or excrescences.

About 200 species: from NE India and Sri Lanka east to Australia and Tahiti, with a well-marked center of diversity in New Guinea; four species (two endemic) in China.