Haw. 1812 not Bonpland 1813 nor Nees 1818
The Duvalia species are succulent, perennial plants with low, planar growth. The stems are clavate, cylindrical to spherical, in cross-section four-, five-or six-edged, and to about 10 inches long. They can range from green, gray to mottled reddish in color.
The flowers are distinctive, and appear to grow from the base of the stems. Each has five thin, elongated lobes, radiating in a star shape from a central raised disk or annulus. The colour of most species flowers is shades of reddish brown, except for those of the rare Duvalia parviflora which are cream-coloured. The flower stems are long and bare. The hermaphroditic flowers measure 1-5 cm in diameter, and have five parts. The crown is yellow ocher, brown, red to dark purple. The five corolla lobes are flat or folded along the middle nerve.
The stems are superficially very similar to those of the related genus Piaranthus, and the two are often confused when not in flower. However Duvalia stems are often five or six sided (Piaranthus are always four-sided).
It occurs in southern Africa. The majority of the species are restricted to the western part of South Africa & Namibia, with the greatest number of species occurring in the Great Karoo region, on the edge of the winter rainfall area. Only one species, Duvalia polita extends further east, and as far north into tropical Africa as Malawi and Zambia.
Four species, occurring on the other side of the continent on the verges of the Red Sea, were formerly included in the genus Duvalia. However phylogenetic studies have shown them to be relatively unrelated to the rest of the genus, and more closely related to genus Ballyanthus Bruyns.
- Duvalia anemoniflora (Deflers) R.A. Dyer & Lavranos - Arabia
- Duvalia angustiloba N.E.Br. - South Africa
- Duvalia caespitosa (Masson) Haw. - South Africa
- Duvalia corderoyi (Hook.f.) N.E.Br. - South Africa
- Duvalia eilensis Lavranos - Somalia
- Duvalia elegans (Masson) Haw. - South Africa
- Duvalia galgallensis Lavranos - Somalia
- Duvalia gracilis Meve - Cape Province
- Duvalia immaculata (C.A.Lückh.) M.B.Bayer ex L.C.Leach - South Africa
- Duvalia maculata N.E.Br. - South Africa
- Duvalia modesta N.E.Br. - South Africa
- Duvalia parviflora N.E.Br. - Cape Province
- Duvalia pillansii N.E.Br. - Cape Province
- Duvalia polita N.E.Br. - South Africa
- Duvalia pubescens N.E.Br. - Cape Province
- Duvalia somalensis Lavranos - Somalia
- Duvalia sulcata N.E.Br. - Arabia
- Duvalia velutina Lavranos - Saudi Arabia
- Duvalia vestita'' Meve - Cape Province
- formerly included
transferred to Mannia
- Duvalia rupestris now Mannia rupestris
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- Haworth, Adrian Hardy. 1812. Synopsis Plantarum Succulentarum: cum descriptionibus, synonymis, locis, observationibus anglicanis, culturaque 44.
- Tropicos Duvalia
- Gibbs Russell, G. E., W. G. M. Welman, E. Retief, K. L. Immelman, G. Germishuizen, B. J. Pienaar, M. Van Wyk & A. Nicholas. 1987. List of species of southern African plants. Memoirs of the Botanical Survey of South Africa 2(1–2): 1–152(pt. 1), 1–270(pt. 2).
- P. Bruyns, C. Klak, P. Hanacek: Evolution of the stapeliads (Apocynaceae-Asclepiadoideae) - repeated major radiation across Africa in an Old World group. Molecular Phylogenetics and Evolution. 2014. v. 77, no. 1, p. 251--263. ISSN 1055-7903.
- The Plant List, Duvalia
Portions of this page were translated from the equivalent page on the German wikipedia accessed July 3, 2012