Description:

• Spiny succulents, small to large, with few to many stems, branching mainly from base
• Stems cylindric, erect (rarely prostrate), glabrous, 25-60(-110) mm thick, covered with obtuse tubercles vertically arranged into 11-31 rows, each tubercle tipped with a weak to hard, sharp spine 3-12 mm long
• Flowers 1 to many in groups, opening successively (rarely simultaneously), near apex of stem
• Calyx lobes overlapping slightly at broad bases, glabrous
• Corolla 8-170 mm diam., small and deeply lobed to large, flat and saucer- to shallowly cup-shaped, lobes valvate in bud, glabrous outside and inside, papillate to smooth within, each papilla ending in a hair
• Corona 2-seriate, arising from staminal column, mostly glabrous; outer corona at least basally cupular, emarginate or bifid towards apex; inner corona of 5 dorsiventrally flattened lobes incumbent on backs of anthers, dorsally connected to outer lobes
• Staminal column arising near base of corolla tube
• Anthers 2-locular, incumbent on top of style head, subquadrate, without apical appendage; style head not produced beyond anthers, truncate-depressed at apex
• Pollinia ± horizontal, with short caudicles
• Follicles terete-fusiform, slender, paired, with horns somewhat diverging, uniformly coloured, glabrous, smooth
• x = 11

Nomenclature:

• Hoodia Sweet ex Decne.
  • Decaisne: 644 (1844)
  • Brown: 896 (1909)
  • White & Sloane: 1050 (1937)
  • Bullock: 508 (1957)
  • Bruyns: 182 (1993)
• Trichocaulon N.E.Br.
  • Brown: 164 (1878) in part
  • Brown: 888 (1909)
  • White & Sloane: 991 (1937)

Distribution & Notes:

• Global: Species 13, Africa
• Southern Africa: Species 12, Namibia, Botswana, Northern Province and western half of South Africa (west of 25°E)