ORCHIDACEAE  

Terrestrial herbs, very rarely epilithic or epiphytic. Stems robust or slender, 0.1-1.0 m tall, with globose or elongate root tubers; occasionally with sterile shoots. Leaves radical, basal or cauline, linear to lanceolate and ovate, conduplicate or flat; green at flowering time, rarely hysteranthous. Inflorescence: raceme or corymb, lax or dense, few- or many-flowered, rarely one-flowered; flowers resupinate or not resupinate, very rarely doubly resupinate; various shades of white, red, pink, yellow, green, brown, purple or blue; bracts usually lanceolate and acute, sometimes dry and membranous. Sepals free, often apiculate; median sepal galeate and normally spurred, spur elongate or sac-like, sometimes obsolete; lateral sepals flat or navicular, spreading, patent or recurved. Petals usually smaller than sepals, ovate-oblong to falcate, basally fused with gynostemium, almost always with prominent anticous lobe, apically often bilobed. Lip linear, narrowly lanceolate, lorate, spathulate or broadly ovate, patent or pendent, margins sometimes crenulate or fringed (some species of Disa sect. Herschelianthe). Gynostemium with erect, horizontally reflexed or pendent anther, thecae parallel and adjacent, anther canals not prominent; pollinia 2, sectile, attached by short or long caudicles to 2 viscidia or rarely to 1 viscidium ( Disa sect. Monadenia); stigma pad-like, pedicellate or sessile; rostellum 3-lobed or unlobed, if 3-lobed with square or horn-like lateral lobes and insignificant or rarely tall and finger-like central lobe. Ovary twisted or untwisted. Capsule cylindrical or narrowly ellipsoid. x= 19 (aneuploids, polyploidy).

Epiphytic monopodial herbs with short or elongate leafy stems, without pseudobulbs. Leaves distichous, ligulate, flat to weakly keeled, unequally bilobed at apex. Inflorescences few- to many-flowered racemes; flowers often translucent, white to yellow-green or beige; bracts usually amplexicaul, rarely prominent. Sepals and petals free, subsimilar. Lip entire or obscurely lobed, with curved spur, often with tooth-like callus at its mouth. Gynostemium short and broad, with or without column-foot; anther operculate; pollinia 2; stipes separate, viscidia 1 or 2; rostellum elongate, tapering or clavate. x= 25 (polyploidy).

Terrestrial herbs, with fasciculate fleshy roots or root tubers. Leaves radical, 1-few. Inflorescence a short or elongated raceme; flowers pink to mauve or white; bracts small and narrow. Sepals subequal; median one often forming hood with petals; laterals oblique, spreading. Petals entire, narrower than median sepal. Lip usually larger than sepals and petals, spurred at base, 3-5-lobed. Gynostemium short and broad; anther thecae parallel and adjacent, anther canals short or long; pollinia 2, sectile, connected to slender caudicles attached to separate viscidia; stigmatic areas on 2 oblong or clavate processes; rostellum several-lobed. Capsule erect, oblong, sometimes shortly beaked. x= 7 (1 report).

Terrestrial herbs, with root tubers. Leaves cauline and basally clustered, narrowly lanceolate, imbricate, flat or sometimes strongly undulate. Inflorescence a dense raceme, many- or few-flowered; flowers normally globose or semiglobose with narrow entrance, resupinate or very rarely nonresupinate, yellow, pink, purple or green; bracts fresh at anthesis but sometimes with dry apices. Sepals mostly fresh at flowering time, sometimes dry and black; median one adnate to petals; laterals +/- fused in basal portion. Petals frequently with posterior sac. Lip basally fused with gynostemium, with flat and wide claw, dilated above into bilobed, transversely lunate, or rarely oblong limb, with stalked shield-like appendage with variously shaped lateral or dorsal processes, rarely appendage elongate or hood-like. Gynostemium: structure very complicated; anther thecae horizontally reflexed or semipendent, situated at far corners of long horseshoe-shaped connective; pollinia 2, sectile, viscidia separate; stigmas convex cushions in median portion of gynostemium, facing upwards, sideways, or downwards. Capsule elliptic or oblong, usually much narrowed above, ribbed.

Terrestrial herbs, with fascicles of furry roots, sometimes also with small tubers. Leaves cauline, linear to lanceolate; basal cluster of linear leaves often present. Inflorescence a lax or dense, elongate or corymbose raceme; bracts linear and often marginally ciliate; flowers resupinate or not, yellow or pink and white. Sepals: median one mostly adnate to petals and +/- reflexed; laterals spreading. Petals mostly unlobed, lanceolate-ovate. Lip basally fused with gynostemium, anchor-shaped, reniform or broadly lanceolate, with or without appendage, frequently with laminar callus. Gynostemium sometimes shortly stalked; anther thecae pendent and apparent as pair of erect or diverging arms (covered by flat rostellum), each with viscidium at its apex, anther canals diverging, short or long; pollinia 2, sectile, often with long caudicles; stigma convex cushions in median portion of rostellum, at dorsal face of gynostemium. Capsule oblong, ribbed.