Polystachya Hook.,
Exot. Fl. 2 (1825) t. 103
(Note: This is a large and highly diverse genus, especially in tropical Africa. The following description only takes into account the Asian species of Polystachya). Sympodial epiphytes with very short rhizomes. Pseudobulbs short, consisting of more than one internode, few-leaved. Leaves sheathing at the base, glabrous, deciduous, duplicate. Inflorescence terminal (synanthous), a many-flowered raceme or a panicle. Flowers small, not resupinate, with a distinct mentum, yellowish. Lateral sepals free. Petals free, simple, narrower than the sepals. Lip not mobile, without spur. Column-foot present. Pollinia 4, solid, caudicles absent, stipe present, viscidium present.
Distribution
Tropics (excluding New Guinea, Australia and East Pacific), predominantly in Africa; about 150 species.
Distribution in the Philippines
Luzon (Mt. Province, Ifugao, Benguet, Pangasinan, Zambales, Bulacan, Rizal, Quezon, Tayabas), Bohol, Mindanao (Lanao); 1 species [Polystachya concreta (Jacq.) Garay & H.R.Sweet].
Habitat
Epiphytes in hill and montane forest.
Notes
Polystachya concreta, which is perhaps the only Asian member of Polystachya, is one of the most widespread of all orchids, being found almost throughout the tropics. It may be recognised by its branching inflorescence carrying yellowish, not resupinate flowers with a distinct mentum. Unlike certain African species, it has minimal horticultural value.