Microcoelia bulbocalcarata L.Jonss., Symb. Bot. Upsal. 23: 121 (1981).
Stem short, up to 12 x 3 mm. Scale-leaves acuminate, with 7-8 nerves, up to 5.0 mm long. Roots few, long, ± pendulous, loosely attached to the substrate, distally sparsely branched, smooth, terete, up to 53 cm x 1.5-2.0 mm. Inflorescence(s) erect, spreading, up to 15 mm long, up to 4 simultaneously, ± dense, each with up to 6 flowers; peduncle short, up to 5 mm long; rachis flexuose, ± terete, smooth, greenish; bracts sheathing, ± acute, 1-nerved, up to 1.6 mm long; pedicel distinct, smooth, up to 5.3 mm long; ovary straight, up to 3.2 x 1.1 mm. Flowers ± horizontal, ascending or descending, up to 15.4 mm long including ovary and pedicel, whitish with a dark green patch on the lip centre; base of sepals dark green with the apex of dorsal sepal pale green; column and anther pale green. Glandular hairs ± densely covering the ovary, more concentrated in the furrows; sparsely on rachis and at base of tepals and spur. Dorsal sepal hooded, bilobed, elliptic, ± acute, subapiculate, with 3 sparsely branched nerves, 4.8-6.3 x 2.6-3.7 mm. Lateral sepals asymmetric, elliptic, acute, slightly convex, shortly connate at the base, with 3 ± branched nerves, thickened along the mid-nerve, 5.2-7.0 x 3.2 mm. Petals ± asymmetric, obovate to ovate, obtuse, slightly convex, with 1 branched nerve, 4.5-6.0 x 3.0-3.8 mm. Labellum oblong, acute; mid-lobe triangular, ± horizontal to decurved, with 3 main nerves; side-lobes indistinct, with a prominent rounded ridge-like thickening on each side of spur moth, 4.2-5.0 x 2.6-3.7 mm. Spur long, ± cylindrical, ± descending vertically, inflated, tapering into a bulbous apical inflation, apex ± incurved, 7.7-10.5 mm long, apical inflation 1.8 x2.5 mm. Column short, truncate, slightly recurved, 1.0-1.3 mm long, up to 1.5 mm high; androclinium shallowly excavated, with a central thickening; rostellum lobes ± horizontal, oblong, acute, with a rectangular membranous process in between, up to 1.3 mm long. Anther ± hemispherical, bivalvate dorsally, in backview cordate, tapering into a triangular prolongation, apex acute, reflexed, 2.0-2.4 x 1.6 mm. Pollinia large, ellipsoid, asymmetric; in side view ± semielliptic to semiovate, 910-1000 x 580-620 in median section elliptic to obovate, up to 630µm thick. Stipes spathulate, apically triangular-shaped, ± sigmoid, 1.4-1.6 x 0.5-0.6 mm (at the apex), brownish; viscidium rounded oblong, convex, tapering into a truncate base, 0.8-1.0 x 0.50-0.55 mm, brownish.
Dense upland forest. Epiphytic on the forest undergrowth. Altitude. 1680-1950 m.
Flowering period:
Recorded from the late rainy season.
As given for the genus, cool growing epiphyte.
Príncipe to Gabon, SW. Uganda to W. Rwanda
African Orchids in the Wild and Cultivation Lacroix 1997; WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017;
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In culture
microcoelia bulbocalcarata
Photograph©Steve Beckendorf. Image used with kind permission.