Duvalia

Duvalia corderoyi

Duvalia is a plant genus in the subfamily milkweed plants ( Asclepiadoideae ) that the Hundsgiftgewächse family ( Apocynaceae ) has been allocated. The genus is named after the French physician and botanist Henri Auguste Duval.

Features

The Duvalia species are stem succulent, perennial plant with low, planar growth. The shoots are clavate, cylindrical to spherical in cross section, four-, five -or six- edged and up to about 10 cm long. They are mottled green, gray-green or reddish. The leaves are very small and triangular.

The flowers usually lying flat on the ground appear near the engine base gradually over a longer period. The flower stems are long and bare. The hermaphrodite, radial symmetry flowers measure 1-5 cm in diameter and are fünfzählig. The crown is yellow, ocher, brown, red to dark purple. The five corolla lobes are flat or folded along the middle nerve. Staminale and interstaminale Nebenkrone have grown into a flat disk. The outer, spindle-shaped pointed extensions of the staminal corona are bent and pointing upward.

The follicles have a length of up to 18 cm and a diameter of up to 1 cm, and containing about 40 to 120 seeds. The flat - elliptical, brown seeds bear a tuft of hair.

Occurrence

The genus Duvalia has a disjoint area and is widespread in the Arabian Peninsula, Somalia and southern Africa.

System

Ulrich Meve and Focke Albers divided in 1990 into the genus Duvalia two sections Duvalia and Arabica. Meve (In: Albers and Meve ) lists 21 species, subspecies and varieties on:

  • Duvalia sect. Duvalia Duvalia angustiloba N.E.Br.
  • Duvalia caespitosa ( Masson ) Haw. With two varieties: Duvalia caespitosa var caespitosa
  • Duvalia caespitosa var compacta ( Haw. ) Meve
  • Duvalia sect. Arabica Meve & F.Albers Duvalia eilensis Lavranos
  • Duvalia galgallensis Lavranos
  • Duvalia sulcata N.E.Br.: With three subspecies: Duvalia sulcata subsp. sulcata
  • Duvalia sulcata subsp. seminuda ( Lavranos ) Meve
  • Duvalia sulcata subsp. somalensis ( Lavranos ) Meve

A dubious name is Duvalia anemoniflora ( Deflers ) RADyer. & Lavranos.

Gentianales Stapeliae Adrian Hardy Haworth Disjunct distribution
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