Description:

• Herbs, geophytes, subshrubs or shrubs; stems often with jointed nodes; usually with aromatic oils in multicellular, capitate-glandular hairs
• Leaves opposite or alternate, usually lobed, often palmately or pinnately dissected or compound, rarely simple and ± entire; stipules usually present
• Flowers bisexual, regular or irregular; on 1- or 2-flowered peduncles or in few- to many-flowered cymose or umbellate inflorescences, rarely solitary and axillary; bracts present or 0
• Sepals (4)5, free or rarely connate to middle, imbricate, rarely valvate, sometimes (Pelargonium) with a tubular, nectariferous spur ± fused with pedicel
• Petals (2, 4)5 (or 0 by abortion), free, equal or unequal, hypogynous or subperigynous, imbricate, rarely contorted
• Disc of 5 nectary glands outside stamens alternating with petals often present, but 0 in Pelargonium which has a nectariferous tube
• Stamens usually twice (rarely 3 times) as many as petals, sometimes reduced to 2, all fertile or some sterile; filaments free or ± connate at base, sometimes connate into 5 bundles of 3 each; anthers versatile, 2-thecous, opening by longitudinal slits
• Ovary superior, consisting of (2)3-5 1-locular carpels with slender styles fused around a central axis (beak, rostrum or carpophore) enlarging in fruit; with 1 or 2 pendulous, axile ovules per locule; styles free at top, with ligulate to clavate, rarely capitate stigmas
• Fruit a 3-5-lobed, rarely 8-lobed schizocarp, breaking up from base of beak into 1(2)-seeded mericarps, usually with persistent, elastic styles as long awns often twisting spirally
• Seeds: embryo usually curved; endosperm 0 or sparse

Nomenclature:

• Geraniaceae
  • Harvey: 254 (1860)
  • Knuth: 129 (1912)
  • Müller: 130 (1963)
  • Merxmüller & Schreiber: 64 (1966)
  • Van der Walt: 1 (1977)
  • Van der Walt & Vorster: 1 (1981)
  • Van der Walt & Vorster: 1 (1988)

Distribution & Notes:

• Global: Genera 11, species ± 800, fairly cosmopolitan in subtropical and temperate regions
• Southern Africa: Genera 5, species ± 290

References:

• HARVEY, W.H. 1860. Geraniaceae. Flora capensis 1
• KNUTH, R. 1912. Geraniaceae. Das Pflanzenreich 4. 129 (Heft 53)
• MERXMÜLLER, H. & SCHREIBER, A. 1966. Geraniaceae. Prodromus einer Flora von Südwestafrika 64
• MÜLLER, T. 1963. Geraniaceae. Flora zambesiaca 2
• VAN DER WALT, J.J.A. 1977. Pelargoniums of southern Africa 1. Purnell, Cape Town, Johannesburg, London
• VAN DER WALT, J.J.A. & VORSTER, P.J. 1981. Pelargoniums of southern Africa 2. Juta, Cape Town
• VAN DER WALT, J.J.A. & VORSTER, P.J. 1988. Pelargoniums of southern Africa 3. National Botanic Gardens, Kirstenbosch

Resources:

• Key to Geraniaceae genera

• Geraniaceae genera: