Current distribution of Calyptrochilum aurantiacum in Central Africa (upper map) and in Cameroon (lower map). WS = Wildlife Sanctuary; FR = Forest Reserve; NP = National Park.

Habitat degradation and forest clearance at the type locality of Calyptrochilum aurantiacum (Mungo River Forest Reserve). In less than 10 years, hundreds of hectares of mature lowland rainforest have been converted to cocoa plantations along the Mungo River (pers. comm. by local communities). A Freshly cleared forest where plantain and bananas will be cultivated during two years prior to being replaced by cocoa trees. B A ten-year old cocoa plantation on the banks of the Mungo River; only a few shade trees remain from the original forest. C Plantain and banana bunches that are harvested every day along the Mungo River. Photographs by V. Droissart (June 2017).

Ecology and habit of natural populations of Calyptrochilum aurantiacum. A Flowering individual growing on upper branches of a felled kola tree, along with the angraecoid orchid Diaphananthe plehniana and the fern Microgramma owariensis. B Dense population growing on 1 metre long branches of Duguetia staudtii. C Calyptrochilum aurantiacum and Diaphananthe plehniana growing side by side on Salacia sp. (Celastraceae). Photographs by V. Droissart (June 2017).

Seed banking of Calyptrochilum aurantiacum in Yaoundé (Cameroon). In 2017, an ex situ conservation programme was initiated to support the long term preservation of C. aurantiacum. A Due to the small size of the flowers, manual pollination has been performed under a stereomicroscope. B Fruit development and maturation takes place in a shadehouse established in Yaoundé. C Finally, viable seeds have been harvested and conserved in the freezer (-20°C). Before being preserved at low temperature, seed viability is assessed using the tetrazolium test (red colouration of living embryo). Photographs A and C by V. Droissart, B by Gyslène Kamdem.