AFRICAN

ORCHIDS

Microcoelia dolichorhiza (Schltr.) Summerh., Bot. Mus. Leafl. 11: 153 (1943).
Homotypic Synonyms:
Angraecum dolichorhizum Schltr., Ann. Inst. Bot.-Géol. Colon. Marseille, III, 1: 192 (1913).
Gussonea dolichorhiza (Schltr.) Schltr., Beih. Bot. Centralbl. 33(2): 425 (1915).
Description:
Stem small, c. 17 mm long, c. 4 mm in diameter. Scale-leaves acuminate, with 5(-7) nerves, up to 4.5 mm long. Roots many, ± free, slender, twisting, ± terete, smooth, distal ends branched, up to 20 cm long, 1-2 mm in diameter, lnflorescence(s) erect, spreading, up to 15 mm long, up to 4 simultaneously, usually dense, each with up to 10-12 flowers; peduncle short, up to 5 mm long; rachis straight to sub-flexuose, carmine rose; bracts sheathing, acute, basal 3-nerved, apical 1-nerved, up to 1.5 mm long. Pedicel long, ± curved, up to 7 mm long, carmine rose; ovary ± straight, faintly furrowed, up to 1.7 mm long, 0.5 mm in diameter, carmine rose. Flowers ± erect, spreading, up to 12.5 mm long including ovary and pedicel; whitish tinged with carmine rose. Glandular hairs ± sparse, on rachis, bracts and pedicel, ovary and at the base of the outer and inner sides of dorsal sepal, and on the outer basal side of lateral sepals and petals. Dorsal sepal ± hooded, obovate, acute, distinctly connate up to c. 1/3 from the base, 3-nerved, c. 3.0 x 1.6 mm. Lateral sepals asymmetric, curved, ovate, acute, distinctly thickened along the mid-nerve and connate at the base, 3-nerved, c. 3.4 x 3.2 mm. Petals small, narrowly triangular, 1-nerved, c. 2.5 x 0.7 mm. Labellum indistinctly 3-lobed; mid-lobe triangular, ± concave, 3-nerved; side-lobes fleshy, cupular, ± closing spur mouth, c. 3.1 x 1.3 mm, mid-lobe alone up to 2.5 mm long; spur ± appressed to ovary and pedicel, ± straight, apex obtusely inflated, c. 5 mm long. Column short, slightly raised, truncate, c. 0.9 mm long, c. 1.0 mm high; androclinium shallowly excavated, ± vertical; rostellum lobes short, ± porrect, acute, con cave, up to 0.9 mm long, each lobe up to 0.35 mm wide. Anther bivalvate at the base; in side view ± oblong, tapering into a distinctly ± truncate recurved apex, up to 1.7x1.1 mm. Pollinia ± discoidal; in side view ± orbicular, with facets, c. 600 x500 µm, in median section — oblong, up to c. 300 µm thick. Stipes ± straight from a curved flattened base, bifid for about 3/4 of the total length, channelled apically, up to 2 mm long; each branch ligulate, tapering into a cupshaped apex, ± circular in outline, up to 500 x 500 µm; viscidium convex, ± oblong, obtuse, base rounded truncate, up to c. 0.8x0.4 mm.
Habitat:
Dense rain forest, epiphytic on tree branches. Altitude. 1000 m.
Flowering period:
Recorded from the early rainy season, i.e., the cyclone time.
Cultivation:
As given for the genus.
Notes:
One of the species in which the stipes is divided in the upper part. Its most striking feature is the presence of two plate-like transverse lamellae one on each side at the mouth of the spur.
Distribution:
N. & NW. Madagascar
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017; http://apps.kew.org/wcsp/
Images:
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