Afrothismia ugandensis sp. nov. (Afrothismiaceae), Critically Endangered and endemic to Budongo Central Forest Reserve, Uganda

Abstract

The fully mycotrophic Afrothismia ugandensis (Afrothismiaceae), formerly described as A. winkleri var. budongensis Cowley, is renamed, redescribed and illustrated from the Budongo Forest in Western Uganda. This change in status is supported by eight newly elucidated qualitative morphological diagnostic characters despite the overall similarity with A. winkleri, a species restricted to Cameroon and Gabon. Afrothismia ugandensis is remarkable in the genus for occurring in semi-deciduous (not evergreen) forest and for having ellipsoid or ovoid (vs. globose) root bulbils. It has only been recorded twice, first in August 1940, and most recently in June 1998, despite targeted searches in recent years. In both 1940 and 1998, only single individuals appear to have been detected. A single site for the species is known with certainty. It is here assessed as Critically Endangered (CR B2ab (iii); D1) using the IUCN 2012 categories and criteria. Afrothismia ugandensis is threatened by forest degradation and clearance due to illegal selective small-holder logging for firewood and charcoal, timber and limited agriculture.