AFRICAN

ORCHIDS

Microcoelia nyungwensis L.Jonss., Symb. Bot. Upsal. 23: 117 (1981).
Description:
Epiphytic plant. Stem short, 10x2 mm. Scale-leaves acuminate to rostrate, with c. 5 nerves, up to 3.6 mm long. Roots few, slender, variously spreading to ± pendulous, loosely attached to the substrate, mostly branched distally, terete, smooth, up to 40 cm x l mm. Inflorescence(s) erect, spreading, up to 30 mm long, up to 7 simultaneously, usually ± dense, each with up to 7 flowers; peduncle short, up to 5 (- 10) mm long; rachis ± straight to indistinctly flexuose; bracts sheating, acute, 1-nerved, up to 1.8 mm long. Pedicel distinct, furrowed, up to 3.5 mm long; ovary straight, distinctly furrowed, up to 2.0x0.7 mm. Flowers ± horizontal, up to 11.5 mm long including ovary and pedicel, whitish. Glandular hairs densely covering the ovary, more scattered on the outer tepals; sparse on the inner tepals, pedicel, base of bracts and rachis. Dorsal sepal hooded, ovate to elliptic, acute, subapiculate, 3-nerved, 4.0-4.7 x 1.6 mm. Lateral sepals asymmetric, ovate, acute, apicu-late, slightly convex, 3-nerved, thickened along the mid-nerve, shortly connate at the base, 4.8-5.6 x 1.8-2.3 mm. Petals ovate, acute, apiculate, with one sparsely branched nerve, c. 3.9x1.6 mm. Labellum large, spathulate, faintly 3-lobed; mid-lobe broadly ovate, ± truncate, subapiculate, ± folded, with c. 7 main nerves with lateral branches; side-lobes narrowly oblong, ± parallel, with a smooth thickening on each side almost closing the spur mouth, 5.6-6.1 x 3.4-3.9 mm; spur long, slender, pendulous, slightly incurved to straight, apically ± obtusely inflated, up to 9.7 mm long (along curve up to c. 11.5 mm long). Column elongated, distinctly recurved, 1.6-1.7 long, 0.9-1.1 mm high; androclinium shallowly excavated, with a central thickening; rostellum lobes attached to the lower 1/3 of the length of the column, ± horizontal, thin, ligulate, connate for 1/2 the length, subacute, up to 1.0 mm long. Anther ± hemispherical, bivalvate dorsally, tapering into an oblong prolongation, apex rounded and recurved, 1.9-2.0 x 1.0-1.1 mm. Pollinia subglobose, asymmetric; in side view ± broadly elliptic, 500-550 x 470-480 µm; in median section broadly elliptic, up to 410 µm thick. Stipes ± curved, bifid for 1/3 to 1/2 of the total length, channelled, each branch ending into an elliptical cup-shaped apex, 1.6-1.7 mm long, up to 300 µm wide; viscidium curved, ovate, acute; at base truncate, distinctly notched, 0.6-0.7 x 0.2-0.3 mm, membranous.
Habitat:
Rain forest. Epiphytic on older branches.Altitude. 1950 m.
Flowering period:
Recorded from the middle of the early rainy season.
Cultivation:
As given for the genus.
Distribution:
W. Rwanda
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017; http://apps.kew.org/wcsp/
Images:
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