锚柱兰属 mao zhu lan shu
Authors:Authors: Xinqi Chen, Stephan W. Gale & Phillip J. Cribb
Leucolena Ridley, J. Linn. Soc., Bot. 28: 340. 1891, not Leucolaena (Candolle) Bentham (1837).
Herbs, terrestrial, small, holomycotrophic. Rhizome narrowly fusiform, tuberous, fleshy, neck sometimes with a few filiform roots. Stem erect, slender, with a few scalelike sheaths, leafless, glabrous. Inflorescence erect, terminal, racemose, with 1 to several flowers; rachis congested, sometimes thickened; floral bracts very small. Flowers erect or spreading, resupinate, often ephemeral, white or pale yellowish brown, small; pedicel elongating in fruit. Sepals and petals connate at base and forming a short tube; dorsal sepal and petals connate for ca. 1/2 their length and forming a porrect hood; lateral sepals usually connate for more than 1/2 of their length, deflexed or weakly spreading; lip adnate with column at base, free from sepals and petals, not spurred, apex entire or weakly 3-lobed; disk with a 2-lobed gland at base and sometimes papillate usually with callus. Column elongate, dilated and with 2 wings at apex, wings attenuate into decurved, filiform stelidia on either side of stigma, lacking a column foot; anther terminal, borne on a long filament; pollinia 4, in 2 pairs, granular-farinaceous, ecaudiculate, each pair directly attached to a sticky viscidium; rostellum erect, transverse, small; stigma broad, placed directly below rostellum. Capsule erect, fusiform.
About eight species: Thailand, SE China, and S Japan (Ryukyu Islands) to the Malay Archipelago; one species in China.
Didymoplexiella is closely related to Didymoplexis but is distinguished from it by the presence of elongate, filiform stelidia that extend from the column wings and by the absence of a column foot.Didymoplexiella is closely related to Didymoplexis but is distinguished from it by the presence of elongate, filiform stelidia that extend from the column wings and by the absence of a column foot.