Description:

• Trees, shrubs, annual or perennial herbs, sometimes spiny or prickly; raphides (needle-shaped calcium oxalate crystals) present or 0
• Leaves opposite or whorled, sessile or petiolate, simple, usually entire
• Stipules interpetiolar (sometimes reduced to an interpetiolar line), sometimes intrapetiolar, often basally fused into a stipular sheath, entire or divided into lobes or fimbriae, often tipped or separated by mucilaginous hairs known as colleters
• Flowers bisexual, rarely unisexual, usually regular, quite often heterostylous with 2 or rarely 3 forms (di-, trimorphic); rarely solitary, mostly in various terminal or axillary, basically cymose inflorescences
• Calyx gamosepalous, (3)4- or 5(-8)-lobed, cup-shaped or tubular, entire, toothed, or lobed, sometimes obsolete, sometimes 1 or more lobes foliaceous
• Corolla gamopetalous, (3)4- or 5(10)-lobed, glabrous or hairy outside and variously hairy within; tube campanulate, funnel-shaped, cylindric, rarely urceolate or saucer-shaped; lobes usually equal, shorter or longer than tube, often reflexed, valvate, contorted or sometimes imbricate
• Disc various, sometimes 0
• Stamens as many as and alternating with corolla lobes, rarely fewer, arising in corolla tube; filaments sometimes 0; anthers 2-thecous, basi- or dorsifixed, usually dehiscing by longitudinal slits, often apiculate, sometimes sagittate, sometimes hairy
• Ovary inferior, rarely half-inferior, 1-10-locular; placentation axile or (in some Gardenieae) parietal; ovules 1-many in each locule, erect, basal or horizontal; style either simple, usually long and narrow and apically divided into 2 or more linear to clavate stigmatic lobes; or ending in an enlarged, variously shaped stigmatic knob (pollen presenter); or ± 0 and with (1)2 long, hairy stigmas (in wind-pollinated Anthospermeae)
• Fruit a drupe, berry or capsule, sometimes crowned with persistent sepals, or indehiscent, or breaking up into cocci
• Seeds small to fairly large, ornamented to smooth, sometimes winged; embryo usually straight and embedded in oily endosperm

Nomenclature:

• Rubiaceae
  • Jussieu: 198 (1789)
  • Candolle: 341 (1830)
  • Sonder: 1 (1865)
  • Hooker: 7 (1873)
  • Hiern: 3 (1877)
  • Schumann: 1 (1891)
  • Phillips: 718 (1951)
  • Verdcourt: 209 (1958)
  • Launert: 1 (1966)
  • Dyer: 602 (1975)
  • Verdcourt: 1 (1976)

Distribution & Notes:

• Global: Genera 630, species 10 200, cosmopolitan but especially tropics and warm regions
• Southern Africa: Genera 61, species 228

References:

• BRIDSON, D.M. 1998. Rubiaceae. Flora zambesiaca 5,2
• CANDOLLE, A.P. DE. 1830. Prodromus 4. Treuttel & Würtz, Paris
• DYER, R.A. 1975. The genera of southern African flowering plants, Vol. 1. Botanical Research Institute, Pretoria
• HIERN, W.P. 1877. Rubiaceae. Flora of tropical Africa 3
• HOOKER, J.D. 1873. Rubiaceae. In G. Bentham & J.D. Hooker, Genera plantarum 2. L. Reeve, London
• JUSSIEU, A.L. DE. 1789. Genera plantarum. Ziegler, Zürich
• LAUNERT, E. 1966. Rubiaceae. Prodromus einer Flora von Südwestafrika 115
• PHILLIPS, E.P. 1951. The genera of South African flowering plants. Memoirs of the Botanical Survey of South Africa No. 25
• ROBBRECHT, E. 1988. Tropical woody Rubiaceae. Opera Botanica Belgica 1
• SCHUMANN, K.M. 1891. Rubiaceae. Die natürlichen Pflanzenfamilien 4,4
• SONDER, O.W. 1865. Rubiaceae. Flora capensis 3
• VERDCOURT, B. 1958. Remarks on the classification of the Rubiaceae. Bulletin Rijksplantentuin, Brussels 28
• VERDCOURT, B. 1976. Flora of tropical East Africa. Rubiaceae (part 1)

Resources:

• Classification of Rubiaceae
• Key to Rubiaceae genera

• Rubiaceae genera: