AFRICAN

ORCHIDS

Microcoelia bispiculata L.Jonss., Symb. Bot. Upsal. 23: 97 (1981).
Description:
Epiphytic plant. Stem short, 2-10(-35) x 2-4 mm. Scale-leaves acute, with c. 5 nerves, up to 4.5 mm long. Roots usually few, variously spreading, loosely crowded, usually twisted and sparsely branched, often attached to almost nothing, terete to slightly flattened where adnate to the substrate, smooth, up to 80 cm x 1.0-1.5 (-2.5) mm. Inflorescence(s) ± erect or pendulous, spreading, up to 70(-195) mm long, up to 4 simultaneously, sparse, each with up to 15 flowers; peduncle distinct, up to 30(—40) mm long; rachis ± flexuose, slightly angular, (transparent rufous); bracts sheathing, acute, indistinctly 1-nerved, up to 1.4 mm long, (russet). Pedicel short, up to 2.0 mm long, (transparent rufous); ovary slightly curved, 0.7-2.1 x 0.2-0.7 mm, (transparent rufous). Flowers ± horizontal, up to 8.7 mm long including ovary and pedicel; tepals pure white, variously tinged with rust brown on the exterior side; labellum with a light-green spicule-shaped thickening at each side of the spur mouth; spur whitish, apically ± darkly greenish-yellow tinged with rust brown; anther and column rust brown. Glandular hairs sparse, scattered on rachis, base of bracts, tepals and spur, ± concentrated in the furrows of the ovary. Dorsal sepal convex, hood-shaped, ovate, acute, with 3 nerves, 3.9-5.2 x 1.9-2.2 mm, with a variously enlarged central band from the base to the apex fading into (rufous). Lateral sepals slightly asymmetric, ± keeled, narrowly ovate, ± acute, subapiculate, with 3 nerves, 4.1-5.0 x 1.3-1.7 mm, with a ± narrow band or only tinged at the apex (rufous). Petals slightly asymmetric, ovate, apiculate, with 1 nerve, 3.4-4.2 x 1.2-1.4 mm. Labellum 3-lobed; mid-lobe obovate, obtuse, slightly keeled and folded apically, 5-nerved, lateral nerves branched; side-lobes small, rounded, at each side of spur mouth beset with a distinct ± spicule-shaped thickening, 3.6-5.5x1.8-3.1 mm; each spicule up to 0.65 mm high, (light viridine yellow) tinged with (rufous) at the very base; spur perpendicular or ± inflexed apically, apex ± spherically inflated, 1.3-2.0 mm in diameter and often tapering into a short obtuse point, 4.6-6.1 x 1.0-1.6 mm, apically tinged with (light viridine-yellow to green-yellow), at the very tip ± (rufous). Column elongated, ± erect, truncate, 1.9-2.8 mm long, 0.8-1.3 mm high; androclinium slightly excavated with a central rounded thickening; rostellum lobes descending, truncate, up to 0.9 mm long, (rufous), margin of stigma whitish. Anther hemispherical in side view, frontally flattened, tapering into an elongated, subacute apex; in median section ± cordate, 1.4—1.7 x 1.0-1.4 mm, (rufous), the very tip whitish. Pollinia subglobose, asymmetric; in side view ± elliptic, 480-590 x 470-580 µm; in median section obovate, 380-520 µm thick, (pale amber yellow). Stipes distinctly sigmoid, ± ligulate, widening into a distinct broader apex, ± rhombic in outline, with an upturned back edge, 1.1-1.4 mm long, apically 0.45-0.80 mm wide, (faint ochraceous-orange); viscidium rectangular, with a rounded front, slightly convex, with ± inrolled sides, 0.6-0.7 x 0.2-0.4 mm, membranous. Capsule straight, cylindric to ellipsoid, 11-15 x 2-3 mm, (transparent rufous); pedicel ± straight, up to 3.0 mm long. Seeds ± cylindrical to fusiform or ± bottle-shaped, testa cells narrowly elongate (in a dry state), sparsely beset with ± club-shaped and hook-shaped processes; anticlinal walls ± sulcate with finer striations, terminal ends ± elongated, (385-)400- 490 (-525) x 40-50 µm (25 dry seeds measured). Scent not percepted.
Habitat:
Dense rain forest, fairly common in more or less undistrubed coastal rain forest, epiphytic mostly in dense understorey vegetation. Often very loosely attached to the substrate, forming more or less cobweb-like formations.
Flowering period:
Mainly at the end of the heavy rainy season (the cyclone time).
Cultivation:
As given for the genus, hot growing epiphyte.
Distribution:
NE. Madagascar
References:
Field Guide tothe Orchids of Madagascar Cribb & Hermans 2009; WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017; http://apps.kew.org/wcsp/
Images:
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