Apocynaceae

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Native

Perennial herbs, climbers, shrubs or trees, usually glabrous; sap usually a milky or sometimes watery latex, often poisonous and sometimes a skin-irritant. Leaves opposite or whorled, rarely alternate or reduced or absent, simple, entire, sometimes glandular near base of lamina; stipules absent. Inflorescence a dichasium or monochasium, raceme, axillary cymose pairs or flowers solitary in axils. Flowers bisexual, actinomorphic, often showy and fragrant; sepals 5, free or partly fused, imbricate or valvate in bud, often with basal glands; petals 5, fused into a tube at base, lobes contorted or valvate in bud, sometimes with a ring of scales in throat; stamens and styles free or fused to form a gynostemium; stamens 5, inserted on corolla-tube or at base of corolla, alternating with lobes, without appendages or with appendages of 2 kinds, dorsal appendages collectively forming a corona, terminal appendages membranous, appressed to style head, filaments free or fused into a sheath around style and fused to it, anthers 2- or 4-celled, enclosed in corolla-tube or exserted, free, cohering to stigma or fused into a sheath and fused to style head, pollen grains separate or coherent, forming waxy pollinia, pollinia in pairs, one from each adjoining anther; ovary superior or rarely half inferior, carpels 2, free or fused, ovules 2 or more per carpel, style 1–2, if 2 united only by a thickened head, stigma 1–5-lobed, on undersurface of style head, in gynostemium alternating with anthers. Fruit a drupe, capsule, berry or follicle, often paired; seeds usually numerous, often flat and comose with long silky hairs, with or without endosperm.

About 400 genera and 4600 species, almost cosmopolitan but mainly in tropical and subtropical regions; 45 genera and 185 species in Australia.

Asclepiadaceae is here included within Apocynaceae. Asclepiadaceae is distinguished from Apocynaceae by having pollen aggregating into pollinia, style and stamens united into a gynostemium, and stamens that often have a corona. However, a continuum in floral morphology occurs between Apocynaceae and Asclepediaceae, with the level of development of the previously mentioned structures related to the degree of pollination specialisation (MacFarlane 1933; Forster 1996) and while Asclepiadaceae have been found to form a lineage in phylogenetic analyses of morphological and DNA data, they are clearly a group that has arisen from a lineage within Apocynaceae (e.g. Sennblad & Bremer 1996; Endress et al. 1996; Potgieter & Albert 2001).

Source: Jeanes, J.A. (1999). Apocynaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 4, Cornaceae to Asteraceae. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2018-04-12
 
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life Life
kingdom Plantae
phylum Tracheophyta
superorder Asteranae
order Gentianales
Higher taxa
family Apocynaceae
Subordinate taxa
genus Alyxia
genus Araujia
genus Asclepias
genus Gomphocarpus
genus Marsdenia
genus Nerium
genus Oxypetalum
genus Parsonsia
genus Tylophora
genus Vinca