''Calyptrochilum'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s from the orchid family

Orchidaceae Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

Kraenzlin, Friedrich (Fritz) Wilhelm Ludwig. 1895. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 22: 30
/ref> native to tropical Africa, with one species extending into Brazil.Kew World Checklist of Selected Plant Families
/ref> Three species are recognized as of 2020: * '' Calyptrochilum aurantiacum'' (P.J.Cribb & Laan) Stévart, M.Simo & Droissart - West Cameroon and Northwest Congo * ''

Calyptrochilum christyanum ''Calyptrochilum'' is a genus of flowering plants from the orchid family Orchidaceae native to tropical Africa, with one species extending into Brazil. Three species are recognized as of 2020: * '' Calyptrochilum aurantiacum'' (P.J.Cribb & Laan) ...

'' (Rchb.f.) Summerh. - Bahia region of Brazil; Africa from Senegal to Ethiopia to Zimbabwe and Mozambique * '' Calyptrochilum emarginatum'' (Afzel. ex Sw.) Schltr. - Africa from Ivory Coast to Central African Republic south to Angola

Taxonomy and naming

''Calyptrochilum'' historically contained two species, ''C. christyanum'' and ''C. emarginatum''. In 2018, the monotypic genus ''Ossiculum'' was moved into ''Calyptrochilum''. The sole ''Ossiculum'' species was ''Ossiculum aurantiacum''; it is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west-central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; the C ...

and is classified as Critically Endangered due to

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

.Pollard, B.J. & Darbyshire, I. 2004.
''Ossiculum aurantiacum''

2006 IUCN Red List of Threatened Species.
Downloaded on 23 August 2007. The original describers of ''Ossiculum'', P.J.Cribb & Laan, noted that the genus closely resembled ''Calyptrochilum'' in terms of floral morphology. In 1986, Gasson and Cribb (1986) found the leaf structure of ''Ossiculum'' and ''Calyptrochilum'' to possess shared characteristics that did not belong to other genera in the

Angraecinae Angraecinae is a subtribe in the family Orchidaceae. The subtribe consists of approximately 18 genera and about 360 species. The type genus is ''Angraecum''. Most of the genera are endemic to Africa, Madagascar and other Indian Ocean Islands, a f ...

. These findings were confirmed in 2006 by Carlsward et al., but ''O. aurantiacum'' remained separate from ''Calyptrochilum'' because of several of its own distinctive features, among them its bright golden flowers. Finally, in 2018, Stévart, M.Simo & Droissart combined the previous morphological and cytological data with genomic information, cementing the position of the former monotypic genus within ''Calyptrochilum''.Simo-Droissart, Murielle & Stévart, Tariq. "New taxonomic and conservation status of ''Ossiculum'' (Vandeae, Orchidaceae), a highly threatened and narrow-endemic angraecoid orchid from Central Africa." PhytoKeys 98: 89 (2018).

References

Sources

* Pridgeon, A.M., Cribb, P.J., Chase, M.A. & Rasmussen, F. eds. (1999). Genera Orchidacearum 1. Oxford Univ. Press. * Pridgeon, A.M., Cribb, P.J., Chase, M.A. & Rasmussen, F. eds. (2001). Genera Orchidacearum 2. Oxford Univ. Press. * Pridgeon, A.M., Cribb, P.J., Chase, M.A. & Rasmussen, F. eds. (2003). Genera Orchidacearum 3. Oxford Univ. Press * Berg Pana, H. 2005. ''Handbuch der Orchideen-Namen. Dictionary of Orchid Names. Dizionario dei nomi delle orchidee''. Ulmer, Stuttgart Vandeae genera Angraecinae {{Vandeae-stub