Summary
A new species of Dioscorea from Morondava prefecture in Western Madagascar is described. Dioscorea bako Wilkin differs from D. alatipes Burkill & H. Perr. by its usually shallowly and irregularly lobed leaf margins, broader leaf blade (grey-green below), longer petiole and the broadly cuneate area where the petiole is inserted onto the leaf blade in the basal sinus. It is pubescent, especially densely on young shoots and inflorescences. It is endemic to Morondava Préfecture and is endangered under IUCN Red List category criteria (IUCN 2001). The unusual morphological features of its inflorescences, some of which are shared with D. alatipes are discussed. Dioscorea bako is a favoured food source for people of the Menabe region and is reported by them to be increasingly hard to find. Immediate conservation measures are necessary to ensure that it remains extant and, in the medium to long term, research should be undertaken to guide its sustainable utilisation.
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References
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Acknowledgements
Thanks are due to the Département des Eaux et Fôrets in Antananarivo for granting collecting permits, and to all those at Parc Botanique et Zoologique de Tsimbazaza, Antananarivo who helped with research and fieldwork. Thanks are also due to the FADES Project (Fonds d’Appui au Développement de l’Enseignement Supérieur), which funded all the research undertaken by the Département de Biologie et Ecologie Végétales on Yams, in particular the field work of Mamy Tiana Rajaonah in the Menabe region. The COLPARSYST programme provided financial support for a visit by PW to the Museum National d’Histoire Naturelle in Paris in October 2003, and the SYNTHESYS programme funded a further visit in October 2006; PW would like to thank Leandro Leoz and all the staff of the Laboratoire de Phanerogamie for their help, especially Jean-Noel Labat and Thierry Deroin. Dave Simpson’s constructive comments improved an earlier version of this manuscript. Odile Weber and Justin Moat prepared the conservation assessment and distribution map. Mark Coode corrected the Latin diagnosis.
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Wilkin, P., Rajaonah, M.T., Jeannoda, V.H. et al. An endangered new species of edible yam (Dioscorea, Dioscoreaceae) from Western Madagascar and its conservation. Kew Bull 63, 113–120 (2008). https://doi.org/10.1007/s12225-007-9000-z
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DOI: https://doi.org/10.1007/s12225-007-9000-z