Description:

• Annual or perennial robust herbs, or shrubs, up to 5 m tall
• Stem rounded at base, 4-angled and 4-grooved at apex, upper 10-25 nodes green, without lenticels, nodes thicker and more hairy than internodes, often with prominent leaf scars
• Leaves crenate
• Inflorescences composed of 3-11 verticils per shoot, dense, spherical, axillary, many-flowered; bracts leaf-like; bracteoles linear, spinescent
• Calyx tubular, 10-nerved, 8-10-toothed; teeth usually rigid, spinescent or rarely almost obsolete; dorsal calyx tooth sometimes dominating, supported by 3 calyx veins
• Corolla tubular, 2-lipped, white, covered by orange-coloured (rarely white) hairs; tube with 1-3 transverse fringes of hairs inside, 2-8 mm above abscission zone; upper corolla lip entire, almost as long as tube, a fringe of longer hairs covering anthers and stigma; lower corolla lip 3-lobed, soon withering and becoming patent or reflexed, lobes subequal or the middle one larger and faintly retuse
• Stamens 4, arising at mouth of corolla, didynamous, lower pair longer; anthers 2-thecous, divaricate, subconfluent
• Disc ventrally enlarged
• Style not bifid, only ventral branch developed and dorsal stigma surface sessile
• Nutlets glabrous, oblong, 3-angled in transverse section, distally truncate and glandular
• x = 6, 7 (polyploidy)

Nomenclature:

• Leonotis (Pers.) R.Br.
  • Persoon: 127 (1807)
  • Brown: 504 (1810)
  • Bentham: 534 (1848)
  • Bentham: 1214 (1876)
  • Briquet: 246 (1896)
  • Baker: 490 (1900)
  • Skan: 374 (1910)
  • Launert & Schreiber: 15 (1969)
  • Iwarsson: 31 (1985)
• Phlomis sect. Leonotis Pers.
  • Persoon: 127 (1807)
• Hemisodon Raf.
  • Rafinesque: 88 (1837)

Distribution & Notes:

• Global: Species 10-15, tropical Africa
• Southern Africa: 3 species are known, widespread