Description :

• Trees or shrubs, often aromatic, dioecious, with indistinct oil cavities in younger parts
• Leaves opposite or subopposite, paripinnate; rachis slightly winged; leaflets asymmetrical, opposite; stipules 0
• Flowers unisexual, regular, in contracted thyrses
• Sepals 4, variously connate or almost free; lobes imbricate or with open aestivation
• Petals 4, free, valvate or imbricate
• Disc annular, intra-staminal, fleshy
• Male flowers : stamens 4, arising at base of disc; ovary 0
• Female flowers : staminodes rudimentary; ovary superior, arising on disc, 2-locular, with a solitary ovule in each locule; styles 2, free or connate; stigmas capitate
• Fruit a compressed capsule, bilobed from apex, cordate at base, 2-locular, 2-seeded, dehiscing along an inner suture, eventually suspended from bipartite axis
• Seeds compressed, with a terminal wing

Classification Notes:

• RbcL sequence data (Gadek et al. 1996) show Ptaeroxylaceae to be a close sister family to Rutaceae , but ongoing research may indicate the recognition of only one family, Rutaceae . ** Subsequently APG II (APG II 2003) classified Ptaeroxylaceae J.-F.Leroy (1960) = Rutaceae

Nomenclature:

• Ptaeroxylaceae
  • Sonder: 242 (1860)
  • White & Styles: 547 (1966)
  • Pennington & Styles: 442 (1975)
  • White & Styles: 35 (1986)
  • Dahlgren & Van Wyk: 52 (1988)

Distribution & Notes:

• Global : Genera 3: the monotypic Bottegoa Chiov. from N East Africa was recently transferred from Sapindaceae (Verdcourt & Davies 1996); Cedrelopsis Baill. with 7 species occurring in Madagascar, and the more widespread Ptaeroxylon confined to Africa
• Southern Africa : Genus 1, species 1

References:

• DAHLGREN, R. & VAN WYK, A.E. 1988. Structures and relationships of families endemic to or centered in southern Africa. Monographs in Systematic Botany from the Missouri Botanical Garden 25
• PENNINGTON, T.D. & STYLES, B.T. 1975. A generic monograph of the Meliaceae . Blumea 22
• SONDER, O.W. 1860. Ptaeroxyleae . Flora capensis 1
• WHITE, F. & STYLES, B.T. 1966. Ptaeroxylaceae . Flora zambesiaca 2
• WHITE, F. & STYLES, B.T. 1986. Ptaeroxylaceae . Flora of southern Africa 18,3

Resources:

• Ptaeroxylaceae genus: Ptaeroxylon