AFRICAN

ORCHIDS

Aeranthes Lindl., Bot. Reg. 10: t. 817 (1824).
Description:
Monopodial epiphytes with short stems. Roots usually fine. Inflorescences axillary, one- to several-flowered, usually unbranched, often pendent, with very slender stalks. Flowers translucent, green or yellowish, rarely white, with the lateral sepals joined to the column foot. Sepals and petals similar, usually acuminate. Lip unlobed, the spur arising from the column foot. Column long or short; pollinia two, stipites two, viscidia two; rostellum side lobes longer than the midlobe.
Distribution:
Zimbabwe, W. Indian Ocean
Habitat:
Brachystegia woodland and evergreen forest, often on rocks
Notes:
The genus Aeranthes was created by John Lindley in 1824. The name is derived from ' the Greek words aer (air, mist) and anthos (flower); it has been suggested that the name means "mist flower," referring to the humid places where these species grow, or to the epiphytic habit.
Aeranthes is a large genus, with more than 30 species once thought to be confined to Madagascar, the Comoro Islands, and the Mascarene Islands. In 1978, however, one species was described from mainland Africa, followed by a second in 1990, both from Zimbabwe. Neither is known to be in general cultivation, but as Aeranthes is a popular genus, the two are likely to become available.
Cultivation:
Species of Aeranthes like high humidity and should never be allowed to dry out completely. All, however, seem very prone to developing fungai spots on the leaves in stagnant air, which can eventually lead to defoliation and death, so good ventilation is important. This would seem to suggest that they would do well mounted, especially with their pendent inflorescences, but the fine roots dry out very easily and we have had most success in growing them in a standard bark mix in pots, which are then suspended. Intermediate temperatures and fairly heavy shade are suitable.
Species from Africa.

Aeranthes africana J.Stewart Zimbabwe (Vuma Mts.).
Aeranthes parkesii G.Will. Zimbabwe (Mt. Nyangani).

Species from Madagascar and Comoro Islands.
As an aid to identification are there here divided these species into 5 groups according to the approximate size of their flowers, dealing with the largest first.
Group 1.
Flowers with very long sepals, including the acuminate tip more than 5 cm long.

Aeranthes antennophora H.Perrier C. Madagascar.
Aeranthes caudata Rolfe Comoros, Madagascar.
Aeranthes grandiflora Lindl. Comoros, Madagascar.
Aeranthes tricalcarata H.Perrier SW. Madagascar.

Group 2.
Flowers with long sepals, including acuminate tip 3-5 cm long.

Aeranthes angustidens H.Perrier NE. Madagascar.
Aeranthes crassifolia Schltr. N. Madagascar.
Aeranthes peyrotii Bosser C. Madagascar.
Aeranthes ramosa Rolfe C. & NE. Madagascar.
Aeranthes schlechteri Bosser N. Madagascar.
Aeranthes unciformis P.J.Cribb & Nusb. North-East Madagascar
Aeranthes virginalis D.L.Roberts Comoros.

Group 3.
Flowers medium-sized, with sepals 2-3 cm long.

Aeranthes aemula Schltr. N. Madagascar.
Aeranthes albidiflora Toill.-Gen., Ursch & Bosser Madagascar.
Aeranthes carnosa Toill.-Gen., Ursch & Bosser Madagascar.
Aeranthes denticulata Toill.-Gen., Ursch & Bosser NE. Madagascar.
Aeranthes filipes Schltr. N. Madagascar.
Aeranthes laxiflora Schltr. N. & E. Madagascar.
Aeranthes leandriana Bosser C. Madagascar.
Aeranthes longipes Schltr. EC. & E. Madagascar.
Aeranthes moratii Bosser N. Madagascar.
Aeranthes multinodis Bosser Madagascar.
Aeranthes nidus Schltr. N. Madagascar.
Aeranthes robusta Senghas C. & NE. Madagascar.
Aeranthes sambiranoensis Schltr. N. Madagascar.

Group 4.
Flowers small, with sepals 1-2 cm long.

Aeranthes bathieana Schltr. C. Madagascar.
Aeranthes campbelliae Hermans & Bosser Comoros.
Aeranthes neoperrieri Toill.-Gen. NE. Madagascar
Aeranthes orthopoda Toill.-Gen. C. Madagascar.
Aeranthes parvula Schltr. N. Madagascar.
Aeranthes polyanthemus Ridl. C. & SE. Madagascar.
Aeranthes tenella Bosser Réunion, N. Madagascar.
Aeranthes tenella var. tenella N. Madagascar.
Aeranthes tropophila Bosser NW. Madagascar.

Group 5.
Flowers very small, with sepals less than 1 cm long.

Aeranthes adenopoda H.Perrier Madagascar.
Aeranthes ecalcarata H.Perrier N. Madagascar.
Aeranthes ambrensis Toill.-Gen., Ursch & Bosser N. Madagascar.
Aeranthes orophila Toill.-Gen. C. Madagascar.
Aeranthes setiformis Garay C. Madagascar.
Aeranthes subramosa Garay Madagascar.

Species from Réunion and Mauritus

Aeranthes arachnitis (Thouars) Lindl. Mascarenes
Aeranthes hermannii Frapp. ex Cordem. Réunion
Aeranthes strangulata Frapp. ex Cordem. Réunion
Aeranthes tenella var. borbonica Bosser Réunion

Imperfectly known species:

Aeranthes dentiens Rchb.f. Comoros, Madagascar.

World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ accessed 21/01/2017
Bibliography and References:
Bosser J. 1971 Contribution a l'etude des Orchidaceae de Madagascar: 15. Nouvelles especes du genre Aeranthes Lindl. Adansonia 11. (1): 81-93 (1971)
Cribb PJ. 1975 A note on the identity of the Madagascan orchid Aeranthes caudata Rolfe. Adansonia 15. (2): 195-197 (1975)
Cribb PJ. 1975 Aeranthes caudata. Curtis's Bot. Mag. 180. (3): tab.685 (1975) Illustrations, coloured illustration
Hermans J, Bosser J. 2003 A new species of Aeranthes (Orchidaceae) from the Comoro Islands. Adansonia 25. (2): 215-217 (2003)
Hillerman F. 1978 Aeranthes neoperrieri: leprechaun from Madagascar? Amer. Orchid Soc. Bull. 47. (4): 310 - 311 (1978)
Hillerman F. 1979 New and pleasant surprises from Madagascar. Amer. Orchid Soc. Bull. 48. (4): 335 - 340 (1979)
McMurtry D. 1987 A second species of Aeranthes in Zimbabwe. S. Afr. Orchid J. 18. (3 & 4): 24-25 (1987)
Pottinger M. 1982 African orchids: Acampe, Aeranthes, Ancistrorhynchus. Angraecopsis and Ansellia Orchid Rev. 90(1062) 132-134 (1982)
Roberts DL. 2005 Aeranthes virginalis (Orchidaceae): a new species from the Comoro Islands. Kew Bull. 60. 139-141
Sheehan T, Sheehan M. 1979 Orchid genera, illustrated: 71. Aeranthes. Amer. Orchid Soc. Bull. 48. (9): 924 - 925 (1979)
Stewart J. 1978 A new species of Aeranthes from Rhodesia - a genus new to Africa. Amer. Orchid Soc. Bull. 47. (8): 719 - 723 (1978)