Family Description
Plants perennial, terrestrial, epiphytic or lithophytic, sometimes mycotrophic; growth monopodial or sympodial; roots adventitious, often aerial, sometimes assimilatory. Stems usually leafy, often with one or more swollen internodes forming pseudobulbs. Leaves usually entire, alternate or opposite, often distichous, plicate or convolute; membranous to coriaceous, often terete or reduced to scale-like bracts, usually sheathed. Inflorescences erect or pendent; spicate, racemose or paniculate, 1- to many-flowered; basal, lateral or terminal. Flowers small to large; zygomorphic; sessile or variously pedicellate; resupinate or non-resupinate. Sepals three, free or connate; dorsal sepal often dissimilar to lateral sepals; lateral sepal sometimes adnate to the column to form a saccate, conical or spur-like mentum. Petals three (medial petal distinguished from the others as the lip), usually free. Lip entire or variously lobed, often with ornamented calluses, with or without a basal spur or nectary. Column short or long, with or without a basal foot, winged or lacking wings; fertile anther one (rarely two or three), terminal or incumbent, cap-like or dehiscing; pollen often agglutinated into discrete masses called pollinia; pollinia mealy, waxy or horny, soft or hard, sectile or not, 2,4,6 or 8, sessile or attached by caudicles or stipes to one or two viscidia forming a pollinarium; stigma 3-lobed, midlobe often modified to form a rostellum. Ovary inferior, unilocular with parietal placentation or rarely 3-locular with axile placentation. Fruit a capsule, usually opening laterally; seeds numerous, dust-like.
Genus Description
Plants terrestrial, small glabrous; tubers cylindric, undivided. Stem with bladeless sheaths are at base. Leaves single or few. Inflorescence terminal, racemose, erect, laxly to densely many-flowered; floral bracts small, lanceolate. Flowers small, often spider-like; ovary sessile. Sepals subsimilar; dorsal sepal free or connivent, hooded; lateral sepals spreading. Petals smaller than the sepals, forming hood with the dorsal sepal. Lip continuous with the column base, spreading to pendent, entire, 2-or 3-lobed, flat concave or obscurely saccate at the base; ecallose. Column short; anther 2-locular, adnate to the face of the column; anther locules parallel; pollinia 2; caudicles very short; viscidia 2, small to large; staminodes prominent; stigma 2-lobed, convex, clavate; rostellum short.
Species Description
Plant 20-60cm tall; tubers small, ovoid, 1.5-2 x 0.5-0.6cm. Stem erect, distantly 2-to 4-leaved, bracteate above leaves; basal sheaths overlapping, tubular, 2.5-7cm long, mouth wide; stem bracts leafy, linear-lanceolate, acuminate, sessile, sheathing at base, 6-20 x 0.4-1.7cm. Inflorescence slender, cylindric, densely many-flowered; rachis glabrous, 4-30cm long; floral bracts ovate-lanceolate to narrowly lanceolate, long-acuminate, 1-veined, 0.3-1.5 x 0.1-0.2cm. Flowers upto 1cm long, uniformly greenish-white; pedicel and ovary fusiform, 5-7mm long. Dorsal sepals concave, ovate, hooded, 1-veined, 2.5-3 x 0.8-1mm; lateral sepals oblique, ovate, obtuse, 1-veined, 2.5-3 x 0.8-1mm. Petals linear-lanceolate, subacurte, hooded, 1-veined, 1.8-2 x 0.5-0.8mm. Lip 3-lobed from a narrow, semi-circular clawed base, 0.8-1 x 0.1cm; lateral lobes long linear-filiform, obtuse; mid-lobe oblong, obtuse. Column 0.8mm long. Fruit ovoid, sessile, erect, 5-7 x 2-2.5mm.
