Afrothismia lovettii sp. nov. (Afrothismiaceae) Critically Endangered (Possibly Extinct) and endemic to the Kihansi Falls Forest, Tanzania

The fully mycotrophic (or mycoheterotrophic) non-photosynthetic Afrothismia lovettii Cheek sp. nov. (Afrothismiaceae), is described and illustrated from the Kihansi Gorge Forest of the Udzungwa Mts, Tanzania where a World Bank-funded hydroproject may have resulted in its extinction, together with the possible extinction of two other narrowly endemic species of mycoheterophic plant, Kihansia lovettii and Kupea jonii (Triuridaceae). The co-incidence of these three species makes (or made) the Kihansi Falls the most important site for species diversity of mycotrophic plants in eastern Africa. In terms of numbers (three) of strict endemic species of this lifeform, the Kihansi Falls is or was, the most important site in Africa together with Mt Kupe in Cameroon. Afrothismia lovettii is similar and may be related to Afrothismia mhoroana Cheek of the Uluguru Mts with which it was confused, differing inter alia in the mainly white, short (6.5-10 mm long), {+/-}monomorphic perianth lobes (vs red, 12 and 20 mm long, di- or tri-morphic) and glabrous (vs hairy) adnate staminal filaments. The provisional extinction risk assessment for Afrothismia lovettii is Critically Endangered (Possibly Extinct) (CR B1ab (iii)+2ab(iii)) using the IUCN 2012 categories and criteria, due to the small area of occupancy and the forest habitat degradation (loss of waterfall spray) resulting from the construction of the World Bank financed Kihansi dam.