Description :

• Annual or perennial herbs or subshrubs; stems and leaves herbaceous, semisucculent or succulent
• Leaves mostly crenate-dentate
• Inflorescences usually terminal, spike-like or paniculate; flowers in verticils, few-flowered cymes or dichasia, or occasionally solitary; bracts small, clearly differentiated from leaves
• Calyx 2-lipped to subequally 5-toothed; when 2-lipped, upper lip consisting of a large single tooth, lower lip of 4 lanceolate-deltoid to subulate teeth; tube glabrous or villous within, sometimes gibbous at base
• Corolla bilabiate; tube usually bent and variously expanded near base, occasionally expanding gradually, rarely straight; upper lip usually 4-lobed, shorter than lower boat-shaped lip
• Stamens 4, rarely 2 abortive, arising at corolla mouth, free or united in a sheath at base, declinate in lower lip of corolla; anthers 1-thecous
• Style lying with stamens in lower lip of corolla; stigma shortly 2-lobed
• Nutlets ovoid or oblong, smooth
• x = 6, 7 (11, 13, 15, 17) (polyploidy)

Nomenclature:

• Plectranthus L'Hér.
  • L'Héritier: t. 41, 42 (1788)
  • Bentham: 29 (1832)
  • Bentham: 62 (1848)
  • Bentham: 1175 (1876)
  • Briquet: 352 (1897)
  • Baker: 398 (1900)
  • Cooke: 266 (1910)
  • Launert & Schreiber: 21 (1969)
  • Codd: 371 (1975)
  • Codd: 137 (1985)
• Germanea Lam.
  • Lamarck: 690 (1788)
  • Hiern: 865 (1900)
• Coleus Lour.
  • Loureiro: 372 (1790) in part
  • Bentham: 47 (1832) in part
  • Bentham: 70 (1848) in part
  • Bentham: 1176 (1876) in part
  • Briquet: 359 (1895) in part
  • Baker: 422 (1900) in part
  • Cooke: 289 (1910) in part
• Neomuellera Briq.
  • Briquet: 186 (1894)
• Burnatastrum Briq.
  • Briquet: 358 (1895)
• Ascocarydion G.Taylor
  • Taylor: 162 (1931)

Distribution & Notes:

• Global : Species ± 300, in tropical and warm regions of the Old World
• Southern Africa : Species 45 widespread but absent from Northern Cape