Ansellia Lindl. in Bot. Reg. 30: sub t. 12 (1844).
Description:
Plants usually epiphytic; stems erect, clustered, swollen into elongate pseudobulbs, to 1 m tall; leaves spaced along the stem, plicate, lorate. Thin and tough, prominently 3-7 nerved. Inflorescences terminal, branched, laxly many-flowered; bracts papery, small. Flowers large, showy, green to yellow and usually prominently spotted brown to maroon. Sepals and petals subsimilar, lorate, usually acute, spreading. Lip 3-lobed; midlobe with 2-3 callus-ridges; side lobes erect, large; ecal-carate. Gynostemium with an arcuate column-part; pollinia 4 in 2 pairs, ovoid.
Type species: Ansellia africana Lindl.
Distribution:
Trop. & S. Africa
Notes:
Only one species of Ansellia is currently recognized in Africa although at least six names have been published for plants from different areas. The flowers are extremely variable, in size, shape, basic colouring, and the colour and size of their characteristic spots. Attempts have been made in the past to relate these differences to the size of the plants, their distribution and ecology, e.g by Piers (1968) and Summerhayes (1937, 1968). But there are often intermediates that do not satisfactorily fit in the various categories proposed. In the recently published account of the Flora of Tropical East Africa, Orchidaceae, Part 2 (Cribb, 1984), only one name is recognized, Ansellia africana, although the great variability within this species is described.
The genus is named in honour of the gardener John Ansell, who first collected specimens on the island of Fernando Po (Bioko) in West Africa. It is immediately recognisable by its large, cane-like pseudobulbs that arise close together from a basal rhizome, often surrounded by a nest of narrow and pointed, upright roots and attached to the host tree or to rocks by many thick white roots. The spotted flowers are home in a branching inflorescence at the apex of each pseudobulb, and, after the first flowering, they also arise from other nodes that have lost their leaves. Plants have been collected in South Africa (Natal) that are pure lemon yellow, lacking spots of any kind.
Cultivation:
This species is very easy to maintain in cultivation in brightly lit, warm conditions. The plants grow well in pots or baskets and form an extensive root system: in well-drained compost. Although wild plants are often found in places that are seasonally quite dry, plants grow hest in cultivation if they are well supplied with water and dilute fertiliser while new pseudobulbs are developing and then kept rather dry to encourage flowering. The flowers are sweetly scented in sunshine and very attractive to bees who pollinate them.
Species:

Ansellia africana Lindl. Trop. & S. Africa.

World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ accessed 1/16/2010
Bibliography and References:
Khayota B. 1993 The genus Ansellia Lindley. Kew Mag. 10. (1): 27-35 (1993)
Piers F. 1977 Ansellia africana Lindl. Orchid Rev. 85. (1010): 233 (1977)
Sheehan T, Sheehan S. 1971 Orchid genera, illustrated: 24. Amer. Orchid. Soc. Bull. 40. (11): 1024-1025 (1971)
Stewart J. 1981 Orchids of Africa: the genus Ansellia. Amer. Orchid Soc. Bull. 50. (3): 248 - 255 (1981)