Description :

• Annual herbs, rarely perennial
• Leaves entire
• Flowers in dichotomous, terminal and axillary cymes
• Calyx 4- or 5-lobed; lobes usually broadly winged
• Corolla 4- or 5-lobed, blue, pink or white; tube short, broadly cylindrical
• Stamens 4 or 5, arising below sinuses; anthers dehiscing by terminal pores or slits
• Ovary 2-locular by intrusion of locular walls; style short; stigma capitate
• Capsule 2-valved, globose; placenta appearing axile
• Seeds many, minute
• x = 17, 31 (9, 14, 15) (polyploidy)

Nomenclature:

• Exacum L.
  • Linnaeus: 112 (1753)
  • Baker & Brown: 545 (1903)
  • Marais & Verdoorn: 211 (1963)
  • Klackenberg: 85 (1985)
  • Paiva & Nogueira: 8 (1990)

Distribution & Notes:

• Global : Species 65, mainly in Madagascar, Socotra, Sri Lanka and S India, but also SE Asia, New Guinea and Australia, 2 on African continent
• Southern Africa : Species 1: Exacum oldenlandioides (S.Moore) Klack., Northern Province and Mpumalanga