Peristylus Blume,
Bijdr. (1825) 404
Terrestrial plants, often with subterranean tubers. Stem elongated, few- to many-leaved. Leaves sheathing at the base, usually broad and crowded, often spirally arranged, glabrous, persistent, convolute, herbaceous. Inflorescence a terminal, few- to many-flowered raceme. Flowers small, resupinate, usually green, brownish, white, or yellowish. Sepals free. Petals free, usually more or less intermediate in shape between the dorsal sepal and the lateral sepals. Lip spurred, not mobile, 3-lobed, spur short, globose, to elongated, clavate to narrowly tubular. Column-foot absent. Pollinia 2, sectile, caudicles present, stipe absent, viscidium present. Stigma with two widely separated, cushion-shaped lobes, which are adnate to the base of the lip.
Distribution
Southeast Asia, Indochina, Japan, Malaysia, Indonesia, the Philippines, Papua New Guinea, Australia, Pacific islands, east to Tahiti; about 70 species.
Distribution in the Philippines
Luzon (Mt. Province, Benguet, Nueva Ecija, Bataan, Cavite, Laguna, Rizal, Batangas), Palawan, Panay, Negros, Cebu, Mindanao (Lanao, Bukidnon); 5 species.
Habitat
Terrestrial in forests and damp open places in the lowlands as well as in the mountains.
Notes
A close relative of Habenaria, and often included in it. The rather insignificant flowers differ from those of Habenaria in the structure of the column, namely in that the stigma-lobes are not situated on stalked appendages, but on cushion-shaped processes which are adnate to the base of the lip. Many species of Peristylus have a very short, swollen and sac-like spur, which is uncommon in Habenaria.