AFRICAN

ORCHIDS

Zeuxine Lindl., Coll. Bot., App.: 1 (1826), nom. cons.
Synonyms:
Adenostylis Blume, Bijdr.: 414 (1825).
Psychechilos Breda, Gen. Sp. Orchid. Asclep.: t. 9 (1827).
Tripleura Lindl., Edwards's Bot. Reg. 19: t. 1618 (1833).
Strateuma Raf., Fl. Tellur. 2: 89 (1837), nom. illeg.
Monochilus Wall. ex Lindl., Gen. Sp. Orchid. Pl.: 486 (1840).
Haplochilus Endl., Ench. Bot.: 113 (1841).
Heterozeuxine T.Hashim., Ann. Tsukuba Bot. Gard. 5: 21 (1986).
Description:
Herbs, terrestrial or rarely lithophytic. Rhizome usually elongate, creeping, fleshy, several noded; roots emerging from rhizome nodes, cylindric, stout. Stem erect or ascending, terete, leafy, glabrous. Leaves cauline or subrosulate, withered or pendulous at anthesis in some species, adaxially green to blackish, sometimes with a white stripe along midvein, linear-lanceolate, obliquely ovatelanceolate, or elliptic, with or without a petiole-like base sheathing stem, sometimes slightly fleshy. Inflorescence glabrous or pubescent, with a few crowded to scattered sheathing bracts and a few to many flowers in a short to elongate terminal raceme; floral bracts usually equal in length to pedicel and ovary. Flowers resupinate or occasionally erect, small, not opening widely; ovary twisted, glabrous or pubescent. Sepals free, similar, outer surface glabrous to pubescent; dorsal sepal concave, forming a hood with petals; lateral sepals enclosing base of lip. Petals connivent with dorsal sepal, nearly as long as dorsal sepal though usually narrower; lip usually adnate to column margin at base, 2- or 3-partite or rarely entire; hypochile concave-saccate to cymbiform, containing 1 to a few scalelike, subulate or lamellate calli on each side at base; mesochile (when present) short, margin often involute and forming a tube, externally glabrous or pubescent and sometimes with a lamellate flange on each side; epichile dilated, entire to 2-lobed. Column short, dilated, with or without a pair of lateral wings; anther ovoid, 2-locular; pollinia 2, each longitudinally parted, granularfarinaceous, sectile, attached either directly to viscidium or via a short tegula; viscidium ligulate-lanceolate to ovate; rostellum conspicuous, erect, bifid; stigma lobes separate, convex, lateral or at apical corners of column. Capsule erect.
Distribution:
Trop. Africa to C. Asia and W. Pacific
Cultivation:
Not in cultivation
Species:

Zeuxine africana Rchb.f. Nigeria, Angola, S. Africa.
Zeuxine ballii P.J.Cribb Malawi to Zimbabwe.
Zeuxine elongata Rolfe Trop. Africa.
Zeuxine gilgiana Kraenzl. & Schltr. WC. Trop. Africa.
Zeuxine lunulata P.J.Cribb & J.Bowden Tanzania (Nguru Mts.).
Zeuxine madagascariensis Schltr. N. Madagascar.
Zeuxine stammleri Schltr. Ivory Coast to WC. Trop. Africa.

 

World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ accessed 1/15/2010
Bibliography and References:
Crouch N, and others. 1994 Zeuxine africana: Durban's odd-ball orchid. S. Afr. Orchid J. 25. (4): 127-129 (1994)
Geerinck D, Lejoly J. 1997 Une nouvelle espece d' Orchidaceae decouverte au Congo: Zeuxine odzalaensis Geerinck et Lejoly. Bull. Jard. Bot. Nation. Belg. 66. (1-2): 153-157 (1997)
McCartney C. 2000 African affinities: part 3. The surprising relationships of some of Florida's wild orchids. Orchids 69. (4): 340-343, 354 (2000)
Ormerod P. 2005 Notulae Goodyerinae (II). Taiwania 50. 1-10 En (Ch)
Plimpton TP. 2001 Zeuxine strateumatica: the mystery surrounding the appearance of this terrestrial orchid. Orchids 70. (4): 330-334 (2001)
Sheehan T, Sheehan M. 1995 Orchid genera illustrated: 165. Zeuxine. Amer. Orchid Soc Bull. 64. (7): 756-757 (1995)
Stern WL, Morris MW, Judd WS, Pridgeon AM, Dressler RL. 1993 Comparative vegetative anatomy and systematics of Spiranthoideae (Orchidaceae). Bot. J. Linn. Soc. 113. 161-197.
Thomas S. 1998 The advance of Zeuxine strateumatica, a new record for Saudi Arabia. Orchid Rev. 106. (1221): 153-154 (1998)