Uvariopsis ebo(Annonaceae) a new, Critically Endangered tree species from the Ebo Forest, Cameroon and a key to the Cameroonian species ofUvariopsis

A new species to science of evergreen forest tree,Uvariopsis ebo(Annonaceae) is described, illustrated, mapped, and compared morphologically with the other cauliflorous species of the genus. Restricted so far to a single site in evergreen lowland forest in the Ebo Forest, Yabassi, Littoral Region, Cameroon, this species is Critically Endangered using the IUCN 2012 standard, because the forest habitat of this species remains unprotected, and there exists threats of logging and conversion to plantations. This species adds to the growing list of threatened species resulting from anthropogenic pressure on Cameroon forests. Observations on the unusual corolla structure of the new species are made. A revised key to the 14 Cameroonian species ofUvariopsisis presented. Notes are given on other narrowly endemic and threatened species in the Ebo forest area, a highly threatened centre of diversity in Littoral Region, globally important for conservation.