AFRICAN

ORCHIDS

Ossiculum aurantiacum P.J.Cribb & Laan, Kew Bull. 41: 824 (1986).
Description:
An erect, monopodial epiphyte with a leafy stem, tall; roars arising from basal part of stem, to 12 cm long, 2 mm in diameter. Leaves distichous, 2-4.5 x 0.6-1 cm, oblong-lanceolate, fleshy, obliquely bilobed at apex, V-shaped in cross-section, set 5-6 mm apart. Inflorescences axillary, to 18 mm long (or shorter than the leaves), densely 9- to 15-flowered. Flowers nonresupinate, fleshy; sepals and petals orange-red, lip yellow. Pedicel and ovary 2-2.5 mm long; bracts 1 mm lang. Dorsal sepal 4 x 1.5 mm, elliptic, acuminate; lateral sepals slightly longer and broader, triangular. Petals 3.5 x 1 mm, oblanceolate, acuminate. Lip entire, 4.5-5 x 3 mm, oblong-obovate, apiculate, with a fleshy callus on each side of the mouth of the spur; Spur1.5-2 mm long, S-shaped, swollen to 1.5 mm in diameter at the apex. Column 0.5 mm long.
Habitat:
Epiphytic on lower branches of trees in primary forest. Attitude not known.
Cultivation:
As given for the genus, warm to cool growing epiphyte.
Notes:
The chromosome number of this interesting species is 2n = 34, a number that is more characteristic of subtribe Angraecinae than of subtribe Aerangidinae, into which it has been provisionally placed. The possibility of introducing the bright color to larger flowers by hybridization is an exciting one-if material of Ossiculum auranti- acum could be obtained.
Distribution:
SW. Cameroon
References:
Angreacoid Orchids Stewart, Hermans and Campbell 2006; 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 21.03.2017
Images:
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