Peristylus Blume

Herbs, terrestrial, slender to robust, medium-sized. Tubers subglobose to ellipsoid-oblong, undivided, fleshy, neck with several slender roots. Stem erect, with 2 or 3 tubular sheaths at base, 1-to many leaved, glabrous. Leaves basal, clustered midway along stem or widely spaced, elliptic, ovate, oblanceolate, or linear, base contracted into amplexicaul sheath. Inflorescence erect, terminal, racemose, glabrous; peduncle often with 1 to several sterile bracts; rachis laxly to densely many flowered. Flowers spirally arranged, resupinate, small, sometimes spidery, green, yellowish green, or white; ovary and pedicel usually erect and held close to rachis, twisted, cylindric-fusiform, slender, usually glabrous. Sepals free; dorsal sepal erect; lateral sepals usually spreading, rarely reflexed. Petals often connivent with dorsal sepal and forming a hood, slightly fleshy; lip connate with column at base, distally 3-lobed or rarely entire, larger than sepals and petals, slightly fleshy, spurred at base, ecallose or with a fleshy callus above mouth of spur; spur short and scrotiform, or sometimes elongate and cylindric, usually much shorter than ovary. Column erect, very short, stout; anther with 2 parallel or slightly divergent locules; pollinia 2, granular-farinaceous, sectile, each attached to a viscidium via a short caudicle; viscidia often small, naked, elliptic, ovate, or suborbicular; rostellum small, with short, inconspicuous arms; stigma lobes 2, basally connate but diverging widely, convex, globose or subclavate, often adnate to base of lip; auricles 2, prominent, placed laterally at base of anther.

These orchids grow in open, grassy habitat or in sheltered forests.