PlantaeDioscorealesDioscoreaceaeWilkinPaulMuasyaA. MuthamaClarifying the Dioscorea buchananii Benth. species complex: a new potentially extinct subspecies for South AfricaPhytoKeys1542015201548517210.3897/phytokeys.48.6806 Dioscorea buchananii subsp. buchananii Description.

Leaves entire to moderately 3, 5 or 7-lobed at stem base and on vegetative stems but then less strongly lobed to entire on reproductive shoots, lobe margins at most weakly undulate; where lobed central lobe usually the largest, maximum length as in species as a whole, broadly ovate to lanceolate or deltoid, lateral lobes oblong to rounded. Male flower pedicel, tepal and torus dimensions as in species as a whole.

Distribution.

Tanzania and Southern and Eastern Congo (Kinshasa) to southern Mozambique, Zimbabwe and Angola.

Vernacular name(s).

See Wilkin (2001, 2009).

Ecology.

Frequently associated with rocky habitats, often in Brachystegia woodland, but also on termitaria, in riverine forest and near mangrove swamps, on limestone and granite substrates; sea level to 1600 m (Wilkin 2001, 2009).

Conservation.

The broad southeastern African distribution of this species indicates that its EOO and AOO will greatly exceed the threshold for threatened IUCN categories (20, 000 km2/2000 km2) (IUCN 2001) and its provisional status is LC.

Uses.

None known.

Specimens examined.

Representative specimens are cited in Milne-Redhead (1975) and Wilkin (2001, 2009).

WilkinP (2001) Yams of South-Central Africa.Kew Bulletin56: 361404. doi: 10.2307/4110963WilkinP (2009) Dioscoreaceae. In: TimberlakeJ (Ed.) Flora Zambesiaca12(2): 109140.IUCN (2001) IUCN Red List Categories: Version 3.1. Prepared by the IUCN Species Survivial Commission, Gland, Switzerland & Cambridge, UK.Milne-RedheadE (1975) Dioscoreaceae. In: PolhillRM (Ed.) Flora of Tropical East Africa. Crown Agents, London.