AFRICAN

ORCHIDS

Oeonia volucris (Thouars) Spreng., Syst. Veg. 3: 727 (1826).
Homotypic Synonyms:
Epidendrum volucre Thouars, Hist. Orchid.: t. 81 (1822).
Aeranthes volucris (Thouars) Rchb.f. in W.G.Walpers, Ann. Bot. Syst. 6: 900 (1864).
Epidorchis volucris (Thouars) Kuntze, Revis. Gen. Pl. 2: 659 (1891).
Heterotypic Synonyms:
Oeonia aubertii Lindl., Bot. Reg. 10: t. 817 (1824).
Oeonia elliotii Rolfe ex Scott-Elliot, J. Linn. Soc., Bot. 29: 55 (1891).
Oeonia humblotii Kraenzl., Bot. Jahrb. Syst. 43: 397 (1909).
Description:
Plants with thin branching, very long, climbing or pendent stems. Leaves sparse, distant, oval-oblong (or elliptical of average size 25 x 8 mm) slightly attenuate toward the sheath, acute apically. Inflorescence much longer than the leaves (30-35 cm), very loosely many flowered. Median sepal and petals obovate oblong, 12 mm long, the petals slightly wider and more acute; lateral sepals more elongated, acule and generally two thirds the length of the labellum. Labellum trilobed; the lateral lobes marginal and untwisted, median lobe unguiculate, obcordiform and deeply notched medially, bilobed, the lobes not attenuate toward the base, slightly diverging and with their margins irregular; with a single cusp in the middle of the notch: papillous basally; spur short 16 mm.), gradually attenuate from the oriface to the apex. Column very short: auricles subsquare, with the inferior angles acute and more developed than the flattened superiors: median tongue of the rostellum thick, recurved and pendent, longer than the auricles. Anther provided on the connective with small, obsolete crest, tongue excised and bidentate; pollina with their cauda retracted: retinacles 2, distinct and widely oval.
Habitat:
Epiphytes of branches; in forests from 0-1200 m alt.; flowering: March-July.
Cultivation:
As given for the genus, warm to cool growing epiphyte.
Distribution:
Mascarenes to Madagascar
References:
The Encyclopedia of Cultivated Orchids Hawkes 1965; An Introduction to the Cultivated Angraecoid Orchids of Madagascar Hillerman & Holst 1986; Flora of Madagascar Perrier 1939/1981; Angraecoid Orchids Stewart, Hermans, 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. 09.03-2017; http://apps.kew.org/wcsp/
Images:
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Habitat/In situ
Oeonia volucris 02
Photograph ©Gilles Grunenwald. Image used with kind permission.

In culture In culture In culture
Oeonia volucris 01 Oeonia volucris  02 Oeonia volucris  03
Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission.

Oeonia rosea Ridl., J. Linn. Soc., Bot. 21: 496 (1885).
Heterotypic Synonyms:
Oeonia oncidiiflora Kraenzl., Bot. Jahrb. Syst. 17: 56 (1893).
Oeonia forsythiana Kraenzl., Bot. Jahrb. Syst. 28: 171 (1900).
Description:
Plants with very long, pendent or climbing slightly branched stems, thin and with numerous leaves, very distant, oval-oblong or elliptical (22-45 x 10-26 mm) rounded-subcordate and embracing the stern basally inflorescences longer than the leaves, very loosely 3-7 flowered, flowers very large (25 mm in diameter), greenish or slightly yellowish, with the labellum white and maculate bright red in its throat. Sepals obovate-oblong (10 x 4 mm above the middle), obtuse and 3 veined. Petals similar to the sepals bin narrower (3 mm). Labellum 25-26 mm long, 4-lobed; inferior lobes rounded, wider than long (5 x 7 mm), median lobes widely flabellate-cuneiform and wider than tall (14-15 mm wide) apically, sometimes sinuate-notched on the internal margins, flat, diverging and each 7 veined; veins several times bifurcate; sprinkled basally with small hairs spur with its oriface wide (5 mm), attenuate from the oriface to the middle, then slightly dilate and obtuse apically, to all of 7 mm long. Column 2-3 mm tall, nearly as wide; auricles sub rectangular (2 x 1.2 mm), median tongue of the rostellum thick, cylindrical, slightly attenuate toward the apes. Papillous, and slightly shorter (1.8 mm) than auricles. Anther provided behind with a flattened, excised-bidentate apicule; pollina yellow, obpiriform, each with its own retracted cauda, inserted in small cupule, hyaline and situated in front of the 2 sub rectangular retinacles (1 x 0.4 mm) and well separated Pedicel 15 mm long.
Habitat:
Oeonia rosea grows epiphytically in tree branches in eastern and central Madagascar, on the plateau as well as on the well-watered eastern slopes, at altitudes of 600 to 1,500 meters. It is indigenous to Madagascar, where it flowers between September and January.
Cultivation:
This little gem has proved difficult to grow. Usually when a shipment of plants is received, they are in a bundle 2 feet long, and will obviously have been cut off at the base, so one knows little about the original size, and many of the "pieces" at the bottom are dead or dying. If left intact and "potted" loosely with sphagnum moss packed about the base, the plants seem to prosper. If "separated," they seem to go downhill—as if they cannot bear to be separated from their "brother" stems. If the roots are potted in bark, they immediately die, for they MUST be left aerial, and they seldom adhere to anything. The species can grow in brighter light but low light is safer until the plant is well established as the leaves bum easily. They do better with high humidity. Seedlings taken from the flask seem particularly difficult to maintain, and probably need to be grown strictly epiphytically. We have had limited success growing this species on slabs with frequent misting.
Notes:
The flowers of this species are quite different for an angraecoid, and they have a bright spot of red in the throat, a lip of almost citron yellow, and sepals and petals of bright green. This absolutely charming little species could be very popular if it were easier to grow. In the meantime, it stands as a challenge to those hobbyists who are determined to grow the difficult. Certainly the rewards are worth the effort.
Distribution:
Mascarenes to Madagascar
References:
AOS Bulletin Vol 48 No 4 1979; AOS Bulletin Vol 53 No 8 1984; Cultivated Angraecoid Orchids Of Madagascar Hillerman & Holst 1986; Flora of Madagascar Perrier 1981; AOS Bulletin Vol 66 No 10 1997; Angraecoid Orchids Stewart, Hermans, 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. 09.03-2017; http://apps.kew.org/wcsp/
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Habitat/In situ Habitat/In situ Habitat/In situ
Oeonia rosea 01 Oeonia rosea 02 Oeonia rosea 03
Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission.

In culture In culture In culture In culture
oeonia rosea 01 oeonia rosea 02 oeonia rosea 03 oeonia rosea 04
Photograph ©Leo Klemm. Image used with kind permission. Photograph ©Leo Klemm. Image used with kind permission. Photograph ©Leo Klemm. Image used with kind permission. Photograph ©Leo Klemm. Image used with kind permission.

Oeonia curvata Bosser in Adansonia22 (2): 231 (2000).
Description:
Long-stemmed epiphytic plants wit unbranched roots. Leaves leathery, ovate, unequally bilobed at the apex, about 2 cm long and 1 cm broad; leaf sheaths persistent, shorter than the internodes. Inflorescences 1-2-flowered, arising at the base of the leaf sheaths. Peduncle stout, obliquely erect, 5-7 cm long; floral bracts broadly ovate, obtuse, 3-4 mm long. Flowers white. Dorsal sepal spathulate, the apex acute, 10 x 5 mm; lateral sepals similar but slightly narrower. Petals narrowly ovate, spathulate, acute, 10-12 x 3 mm. Lip 25 mm long and broad, four-lobed; side lobes broad, erect, rounded, the margins undulate; terminal lobes smaller and narrower, falcate, the apices truncate, separated by a narrow sinus; base of lip funnel- shaped, prolonged into a cylindrical spur 13-15 mm long, slender, curved, the tip obtuse. Column 2 mm long; anther hemispherical, truncate in front.
Notes:
This rare and little-known species resembles Oeonia madagascariensis in the shape of the spur but differs in the falcate terminal lip lobes separated by a narrow sinus and in the shape of the anther, which is hemispherical and truncate in front (in Oeonia madagascariensis, the anther has a bilobed projection on the apex).
Habitat:
Grows in mid-altitude forest, between 1,200 and 1,400 m. Apparently it has only been collected once, in the Ranomafana National Park.
Cultivation:
As given for the genus, cool growing epiphyte.
Distribution:
Endemic to Madagascar
References:
Field Guide to the Orchids of Mdagascar Cribb & Hermans 2009; WCSP (2017). 'World Checklist of Selected Plant Families. 09.03-2017; http://apps.kew.org/wcsp/
Images:
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Habitat/In situ Habitat/In situ
Oeonia curvata 03 Oeonia curvata 04
Photograph ©Gilles Grunenwald. Image used with kind permission. Photograph ©Gilles Grunenwald. Image used with kind permission.












Oeonia madagascariensis (Schltr.) Bosser, Bull. Mus. Natl. Hist. Nat., B, Adansonia 1984: 370 (1984).
Homotypic Synonyms:
Perrieriella madagascariensis Schltr., Repert. Spec. Nov. Regni Veg. Beih. 33: 366 (1925).
Description:
Plants thin, stems pendent to 15 cm long leaves very numerous, small and narrow (20-25 x 3-5 mm), obtuse and slightly fleshy. Inflorescence equaling the length of the leaves or slightly shorter, one flowered but with the rudiments of a second; peduncle 12-14 mm long, bearing 1-2 short basal sheaths, the remainder hare, bracts deltoid much shorter than the pedicel; flowers small, greenish. Median sepal concave, slightly obovate (6 x 3 mm) obtuse with 5 slightly visible veins; lateral sepals of the same form, but longer and narrower (7 x 2.5 mm,), Petals smaller (5 x 2.3 mm), margins carinate, 3 veined. Labellums inferior lobes rounded, wider than long (2.5 mm), denticulate-carinate on the forward margins; middle lobe with a short, wide isthmus (1 x 3 mm) and narrowly transversed lamina (3 x 7-10 mm), lateral edges rounded and the lower and lateral margins crenate; labellum and spur obscuring the remainder of the flower, sub-horizontal, undulate in the form of an S; spur not noticeably attenuate to the spur oriface, which is widest apically, cylindrical and thin, 12 mm long. Column wider than long (l mm), auricles obliquely ascending, attenuate, obtuse, 2.5 mm long and 1.2 mm wide basally, clinandrium villous and with obscure margins, median lobe of the rostellum lingulate, thick, obtuse and villous above. Anther with a connective appendage, visibly thickened, slightly verrucose above, provided frontally with a very long (2 mm), narrowly deltoid, attenuate, bifid rostrum; pollina l mm in diameter; cauda hyaline and slightly attenuate frontally, 2 mm long; viscidiums very long, narrowly elliptical, opaque and white, turned tip behind the rostellum. Pedicel 6 mm long,
Habitat:
Pendent epiphytes; in mossy forests, from 2000 m alt.; flowering in January.
Cultivation:
As given for the genus.
Distribution:
N. Madagascar
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 09.03-2017; http://apps.kew.org/wcsp/
Images:
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Oeonia brauniana var. sarcanthoides (Schltr.) Bosser, Bull. Mus. Natl. Hist. Nat., B, Adansonia 11: 162 (1989).
Homotypic Synonyms:
Oeoniella sarcanthoides Schltr., Repert. Spec. Nov. Regni Veg. Beih. 33: 364 (1925).
Lemurella sarcanthoides (Schltr.) Senghas, Schlechter Orchideen 1(16-18): 1018 (1986).
Heterotypic Synonyms:
Oeonia subacaulis H.Perrier, Notul. Syst. (Paris) 7: 138 (1938).
Lemurella tricalcariformis H.Perrier, Notul. Syst. (Paris) 14: 164 (1951).
Description:
Plants sub acaulis or with a stem 5-6 cm long and 2 mm in diameter; sheaths heavily striate, 10 veined generally, leaves 4-5 generally, oblong (2.5-4.5 x 1-1.2 cm), attenuate toward the base and slightly acute apically. inflorescence from in the sheaths of the inferior leaves, shorter titan the leaves, 2 or 3 flowered, with the sepals and petals of a yellowish or slightly greenish and the labellum white, maculate with red at the base of the median lobes; peduncle 1-2 cm long, clad basally with several sheaths; bracts loose, subacute, 2.5-3.5 mm long. Median sepal oblong (10 x 4.5 mm), attenuate from the upper third to the base, obtuse and slightly emarginate apically, obscurely triveined the laterals free, similar to the median sepal, but thickly cucullate apically and shortly apiculate. Petals same as the median sepal, but narrower (10 x 3.5 mm). Labellum embracing the column and very concave basally, densely pubescent above, thick, deeply 5-lobed, 8 mm bong and 10 mm wide between the tips of the lobes; lateral lobes obovate (6 x 3.5 mm) 5 veined: the intermediaries oblong-obtuse (4 x 2.2 mm), 3 veined; the apicals shorter titan the laterals, orbicular (2.5 mm in diameter), emarginate apically and 5 veined; spur short, cylindrical. Anther with a slightly swollen connective in front with the margin obvious, excised medially, with the side margins upturned behind; pollina spherical (0.5 mm), sessile, in 2 small cupules, joined apically by a 0.5 mm long bandelett, attenuate flattened in a wide gland in the form of a hemispherical crown, 1.2 mm wide and hollowed below. Column thicker (3 mm) than tall (2 mm); auricles l mm long, very obtuse, recurved sickle-shaped behind, median tongue of the rostellum thick, spatulate-obtuse longer than the auricles. Pedicel 6-8 mm long.
Habitat:
Epiphytes of branches; in eastern forests, from 700 m alt.; flowering in February.
Cultivation:
As given for the genus.
Distribution:
N. & E. Madagascar
References:
WCSP (2017). 'World Checklist of Selected Plant Families. 09.03-2017; http://apps.kew.org/wcsp/
Images:
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