AFRICAN

ORCHIDS

Microcoelia konduensis (De Wild.) Summerh., Bot. Mus. Leafl. 11: 154 (1943).
Homotypic Synonyms:
Angraecum konduense De Wild., Not. Pl. Util. Congo 1: 321 (1904).
Gussonea konduensis (De Wild.) Schltr., Beih. Bot. Centralbl. 36(2): 93 (1918).
Heterotypic Synonyms:
Dicranotaenia dahomeensis Finet, Bull. Soc. Bot. France 54(9): 47 (1907).
Gussonea dahomensis (Finet) Schltr., Beih. Bot. Centralbl. 36(2): 92 (1918).
Microcoelia dahomeensis (Finet) Summerh. in J.Hutchinson & J.M.Dalziel, Fl. W. Trop. Afr. 2: 454 (1936).
Description:
Stem short, in older specimens often stout and noticeably swollen at the joints with the inflorescences, up to 10(—50) x ( 1.5—)2—3 (-6) mm. Scale-leaves acuminate to rostrate, 5(—12) nerved, 3—5(—6) mm long. Roots many, mostly slender, predominantly very slender terminally, variously spreading, densely crowded, mostly variously twisted and usually with many braches, ± firmly attached to the substrate with terminal ends ± loose, terete, smooth, up to 50(—70) cm x 0.5-1.5 (-2.5) mm. Inflorescence(s) ± descending, spreading, up to 150(-200) mm long, up to 15(—25) simultaneously, usually ± dense, each with up to 15(—30) flowers; peduncle short, up to 10 mm long; rachis straight to indistinctly flexuose, stiff, ± terete, slightly furrowed; bracts sheathing, acute to subacuminate, basal bracts up to 5-nerved, apical bracts indistinctly 1-nerved, up to 2.5(—3.5) mm long. Pedicel short, ± curved and twisted, up to 2.3 mm long; ovary ± curved and twisted, (1.0-)1.3-2.0 x (0.3-)0.5-0.8 (-1.0) mm. Flowers mostly twisted into a ± horizontal position, up to 11(—15) mm long including ovary and pedicel, whitish; sepals tinged in orange-brown or salmon-coloured at the base and sometimes also into a central band; labellum white tinged with apple-green around the spur mouth; spur apex orange-brown to salmon-coloured as the anther and column. Glandular hairs ± densely covering the ovary, sparsely on the rachis, bracts, pedicel, base of tepals and spur. Dorsal sepal hooded, oblong to elliptic, acuminate, ± keeled apically, 3-nerved, (2.4—)3.1—5.3(—6.3) x 1.1—2.0 mm. Lateral sepals asymmetric, narrowly ovate to ovate, ± curved, convex, acute, ± apiculate, 3-nerved, (3.0-)4.0-6.6(-7.7) x (1.0-)1.3-2.3(-2.7) mm. Petals slightly asymmetric, narrowly ovate, acute, subapiculate, 1-nerved, sometimes branched, 2.2-6.1(-6.5) x (0.5-)0.8-1.6 (-2.1) mm. Labellum large, indistinctly 3-lobed; midlobe spathulate, ± folded, ± orbicular to broadly transversely elliptic, obtuse to slightly emargi-nate, apically ± erose, 5-nerved, lateral nerves with branches; side-lobes indistinct, narrowly oblong, irregularly thickened towards the spur mouth, (2.8-)4.5-7.91-10.3) x (1.4-)2.2-6.01-7.7) mm; spur distinctly incurved, obtuse, ± cylindrically inflated apically, 2.0-4.8 mm long, along the curve up to 13 mm long, apical inflation up to 2.0 mm in diameter. Column elongated, distinctly recurved, 1.0-2.3 (-3.2) mm long, (0.5-) 0.7-1.3 (-1.5) mm high; androdinium shallowly excavated with a minute hump in the centre; rostellum-lobes ± horizontal, in early anthesis ± pointing into the spur mouth, fleshy, ± narrowly wedge-shaped, up to 1.2 mm long. Anther ± hemispherical in side view, bivalvate dorsally, tapering into an oblong prolongation, apex subacute and ± incurved, (1.4-11.7-3.3 (—4.2) x (0.6—)0.9—1.1 mm. Pollinia subglobose, ± asymmetric; in side view ± elliptic, (500—) 530-690 (-780) x (410-)440-530 (-600) µm in median section obliquely oblong, the side attached to the stipes ± flattened, up to 400 pm thick. Stipes indistinctly sigmoid, bifid for c. 1/4 of the total length, channelled, each branch apically cup-shaped and ± ovate to ± circular in outline, 1.7—2.9(—3.6) mm long, each cup up to 0.5 mm wide (longest axis); viscidium small, narrowly elliptic, acute, truncate distally, ± curved, 0.6-1.1 x 0. 1-0.3 mm, membranous. Capsule ± ellipsoid to subglobose, 7-10x3-4 mm; pedicel short ± straight, 1.6-2.5 mm long. Seeds fusiform to bottle-shaped, testa cells narrowly elongate (in a dry state), with ± loopshaped and indistinctly club-shaped processes, anticlinal walls ± sulcate with finer striations, distinctly spirally sculptured, terminal ends indistinctly elongated, (320-)400-550 (-740) x (40-)50-70,µm. Scent sickly sweet, on the whole only fragmentarily recorded which could be indicative of a nocturnal periodicity.
Habitat:
Epiphyte in rain forest, also in plantations and secondary vegetation; on small branches and twigs in the crown of trees; 50-500 m; flowering April to June and September to December.
Flowering period:
Two flowering periods occur at each rainy season, mainly located at the beginning and end of the rains.
Notes:
Described from such poorly preserved material that no details are available of many of the floral parts. It appears to be a relative of Microcoelia caespitosa (Rolfe) Summerh. but may be more correctly placed in section Dicranotaenia.
Cultivation:
As given for the genus, hot growing epiphyte.
Distribution:
W. Trop. Africa to Uganda
References:
A Monograph of the Genus Microcoelia [Orchidaceae] Jonsson 1981; WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017; http://apps.kew.org/wcsp/
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