Taxonomic revision of the African genus Greenwayodendron (Annonaceae).

Greenwayodendron (Annonaceae) is a tropical African genus of trees occurring mainly in rain forests. Until recently, Greenwayodendron contained only two species: Greenwayodendronoliveri from West Africa and Greenwayodendronsuaveolens from Central and East Africa. Genetic data, using chloroplast haplotypes and nuclear microsatellites as well as morphometric analyses, provided important information on the delineation of species. Greenwayodendron now contains six species, including two new species ( Greenwayodendronglabrum Lissambou, Hardy & Couvreur, sp. nov. and Greenwayodendronlittorale Lissambou, Dauby & Couvreur, sp. nov. ). Greenwayodendronsuaveolensvar.gabonica and Greenwayodendronsuaveolenssubsp.usambaricum are recognised as distinct species: Greenwayodendrongabonicum comb. nov. and Greenwayodendronusambaricum comb. nov. , respectively. A key, detailed descriptions of morphology and geographic distributions, as well as notes on their ecology and uses are presented for all species. Preliminary conservation assessments following IUCN criteria are also provided. Two species are preliminarily identified as threatened, one as Endangered and one as Vulnerable.