AFRICAN

ORCHIDS

Microcoelia perrieri (Finet) Summerh., Bot. Mus. Leafl. 11: 147 (1943).
Homotypic Synonyms:
Rhaphidorhynchus perrieri Finet, Notul. Syst. (Paris) 1: 89 (1909).
Angraecum perrieri (Finet) Schltr., Ann. Inst. Bot.-Géol. Colon. Marseille, III, 1: 198 (1913).
Gussonea perrieri (Finet) Schltr., Beih. Bot. Centralbl. 33(2): 425 (1915).
Description:
Epiphytic or occasionally epilithic plant. Stem up to 3—55(— 100) x 1.5—4 mm, occasionally stout and proliferous. Scale-leaves ± rostrate, up to 8 mm long, with 4-8 nerves. Roots few to many, often rather stout, variously spreading, densely to loosely crowded, mostly closely adnate to the substrate, sometimes with few side branches, ± flattened to rounded triangular in TS, apical free parts ± terete and slightly twisting, smooth, up to 40 cm x(1.0-)1.5-3 mm. Inflorescence(s) mostly characteristically appressed to the stem, pointing forwards or slightly spreading, up to (30—)95 mm long, up to 40 simultaneously, usually dense, each with up to 26 flowers; peduncle short, up to 15 mm long; rachis straight, ± terete, smooth; bracts sheathing, ovate, acute or subacute, 1-nerved, up to 2.0 mm long. Pedicel long, ± terete, 3.2-6.6(-7.4) mm long; ovary ± straight, slightly furrowed, 1-2x0.3-0.6 mm, reddish brown. Flowers ± horizontal, up to 5.5 mm long including ovary and pedicel, whitish. Glandular hairs very sparsely present, at the base of bracts and tepals, ± concentrated in the furrows of the ovary. Dorsal sepal hooded, ovate, ± acute, apiculate, with 3 nerves, (1.4—) 1.7-2.3 x 0.9-1.4 mm. Lateral sepals asymmetric, slightly convex, ovate, ± acute, apiculate, with 3 nerves, thickened along the central nerve, (1.9-)2.1-2.8x (1.4—) 1.6—2.3(—2.5) mm. Petals ± obovate, acute, ± apiculate, with 1 nerve, 1.2-1.9x0.7-1.2(-l.6) mm. Labellum 3-lobed; mid-lobe ± semiorbicular when outspread, subapiculate or not, ± folded in natural position, with 5 nerves, lateral nerves with few branches; sidelobes rounded, slightly thickened, cup-shaped around the spur mouth, 2.5-3.2 (—3.5) x (1.2—) 1.4-2.l (-2.4) mm; spur ± perpen dicular, slightly curved, cylindrical, tapering into a ± distinct obtusely conical inflated apex, (5.1—)5.4-6.1 (-6.3) mm long, inflated apex 0.9-1.2 mm in diameter. Column short, ± pointing dorsally, 0.4-0.6(-0.8) mm long, (0.5-)0.6-0.9 mm high, with a prominent ± circular stigmatic area; androclinium distinctly excavated, mid-ridge ± prominent; rostellum lobes slightly protruding, obtusely deltoidal, ± verrucose at the very apex, up to 0.5 mm long. Anther hemispherical in side view, tapering into a short ± obtuse prolongation, in back view rounded triangular, 0.8-1.1 x 0.7— 1.0(—1.1) mm, greenish. Pollinia subglobose; in side view slightly asymmetric, irregular, ± obovate to elliptic, (360-)380-490(-500) x (330-) 340-460(-500) µm: in median section obovate to elliptic, up to 400 µm thick. Stipes ligulate, slightly spathulate towards the apex, ± sigmoid, (580-)590-710(-780) µm long, (90-) 100-160(-200) µm wide apically; viscidium elliptic to obovate, ± convex, 310-470 x 170-230 µm, membranous. Capsule ellipsoid to cylindrical, 3.4-5.5 x 1.6-1.8 mm, reddish brown; pedicel distinct, up to 7.5 mm long. Seed ± bottle-shaped, testa cells narrowly elongate, with distinct club-shaped processes; anticlinal walls ± sulcate, with finer striations or not, c. 450x40 pm (only one seed from an old capsule has been seen).
Habitat:
Epiphyte of branches; from tropical forests between 0-100 m alt.
Flowering period:
Mainly during the dry season.
Cultivation:
As given for the genus, hot growing epiphyte.
Notes:
Well characterised by the long slender rhachis and hair-like pedicels and the almost cylindrical spur about three times as long as the lip lamina and slightly constricted about one-third below the apex. The rostellum and stipes are short and the general structure strongly resembles that of Microcoelia hirschbergii Summerhayes described above. Microcoelia perrieri, however, has much longer inflorescences, the perianth members more unequal especially the very oblique lateral sepals, the spur longer and constricted nearer the apex, and a relatively smaller viscidium.
Distribution:
N. & W. Madagascar
References:
A Monograph of the Genus Microcoelia [Orchidaceae] Jonsson 1981; African Orchids In the Wild and Cultivation La Croix 1997; Angraecoid Orchids Stewart, Hermans and Campbell 2006; Orchids of Madagascar Hermans 2007; Field Guide to the Orchids of Madagascar Cribb & Herman 2009; WCSP (2017). 'World Checklist of Selected Plant Families. 03.03-2017; http://apps.kew.org/wcsp/
Images:
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In culture In culture In culture In culture In culture
Microcoelia perrieri  01 Microcoelia perrieri  02 Microcoelia perrieri  03 Microcoelia perrieri  04 Microcoelia perrieri  05
Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission.