A taxonomic revision of the baracoffea alliance: nine remarkable Coffea species from western Madagascar

A taxonomic revision of the baracoffea alliance, formerly Coffea subgenus Baracoffea, is presented. Identification keys, descriptions, distribution maps, illustrations, species notes (distribution, habitat and ecology, phenology) and conservation assessments are provided. The taxonomic history and the morphology of the alliance is elucidated and discussed. The baracoffea alliance comprises nine species and two subspecies; six species and one subspecies are described as new to science. The six new species dramatically broaden the morphological limits of the baracoffea alliance, and of Coffea itself, particularly as a result of the discovery of species with distinctly winged fruits, extra-axillary domatia and seeds with shallowly ruminate endosperm. The baracoffea alliance is endemic to western Madagascar and is confined to seasonally dry vegetation types. (C) 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 355-390.