Plectrelminthus Raf., Fl. Tellur. 4: 42 (1838).
A genus with only one species in West Africa, Plectrelminthus caudatus, which is not uncommon. It is a large, sturdy epiphyte with a long, rather sparsely-flowered inflorescence and thick aerial roots. The flowers are quite large and conspicuous mainly because of the long, characteristically looped spur. The lip has a long, pointed middle lobe.
W. & WC. Trop. Africa
The plant is easily cultivated in humid conditions.

A key to the genus Plectrelminthus Raf. 

Bibliography and References:
Carlsward BS, Stern WL, Bytebier B. 2006 Comparative vegetative anatomy and systematics of the angraecoids (Vandeae, Orchidaceae) with an emphasis on the leafless habit. Bot. J. Linn. Soc. 151. 165-218.
Cavestro W. 1998 Plectrelminthus (Lindley) caudatus Summerhayes, une remarquable orchidee africaine. Orchidophile 29. (130): 5-7 (1998)
Gasson P, Cribb PJ. 1986 the leaf anatomy of Ossiculum aurantiacum Cribb & van der Laan (Orchidaceae: Vandoideae). Kew Bull. 41. 827-32.
La Croix I. 1994 The Angraecoid orchids: 5. Rangaeris, Listrostachys, Summerhayesia and Plectrelminthus. Orchid Rev. 102. (1197): 129-132 (1994)
Leroux A. 1990 Plectrelminthus caudatus (Lindl) (Afrique centrale). Orchidophile 21. (92): 103-104 (1990)
Pottinger M. 1982 African orchids. Plectrelminthus to Ypsilopus. Orchid Rev. 90. (1070): 384-385 (1982)
World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; accessed 12.03.2017