Description:

• Trees, erect or scandent shrubs, shrublets, subshrubs, lianas, perennial, rarely annual herbs, often succulents, glabrous or pubescent, with milky or clear sap
• Leaves opposite, sometimes whorled or decussate, rarely alternate or fascicled, simple, entire, pinnately veined, in some succulents reduced to small rudiments or spines; stipules, if present, usually intrapetiolar, rarely on each side of petiole, minute to short, rarely spinose; colleters (mucilaginous hairs) often present at junction of petiole and lamina
• Inflorescence mostly a cyme, sometimes racemose or umbelliform, terminal to axillary, sometimes flowers solitary
• Flowers regular, bisexual, small to large and showy, usually bracteolate, sometimes fragrant, occasionally with an obnoxious smell
• Calyx of 5(4) sepals, free or slightly united at base, rarely forming a tube; mostly with paired, ± alternisepalous, basal, adaxial colleters
• Corolla gamopetalous, 5(4)-lobed to 5(4)-fid, rotate to tubular; lobe aestivation dextrorse (overlapping to the right) or sinistrorse (to the left) or valvate; a corolline corona sometimes present
• Corona of 5 or more, free or fused lobes in 1 or 2(3) series often present, either on corolla or arising from or near base of staminal column
• Disc annular or cupular or of 2-5 scales usually present in Apocynoideae
• Stamens 5(4), either arising on corolla tube and alternating with petals, or conniving in a cone around style head, or fused into a tubular staminal column (gynostegium) with anthers fused to style head; anthers 2-thecous, either 2- or 4-locular, sometimes with apical appendix, tailed at base or winged; pollen grains in monads, tetrads or united into waxy pollen masses (pollinia), dispersed singly, in translators or in pollinaria comprising 2 or 4 pollinia attached by caudicles (translator arms) to a corpuscle (corpusculum, clip, gland, pollen carrier)
• Nectary, if present, in a ring around base of ovary or in 5 alternisepalous troughs at base of filaments or staminal column
• Ovary superior to half-inferior, of 2 carpels, either entire and 1- or 2-locular with (1-4) or many ovules on an axile placenta, or carpels ± free to partly connate, each carpel with (1)-many ovules on a single, ventral, marginal placenta; style 1 or carpels ± free except towards base and towards apex and dilated at apex into style head comprising anthers
• Fruit a berry, drupe, samara, or a pair (often 1 by abortion) of ventrally dehiscent follicular or baccate mericarps
• Seeds often compressed, often with a tuft of silky hair (coma) at micropylar end, sometimes with marginal wing; embryo straight; endosperm present

Classification Notes:

• Apocynaceae, as circumscribed here, includes Asclepiadaceae and Periplocaceae

Nomenclature:

• Apocynaceae
  • Leeuwenberg: 1213 (1994)
  • Liede & Albers: 201 (1994)
  • Struwe et al.: 175 (1994)
  • Takhtajan: 434 (1997)
  • Venter & Verhoeven: 705 (1997)

Distribution & Notes:

• Global: Genera 480, species 4800, mostly tropical and warm (especially Africa), few in temperate regions
• Southern Africa: Genera 89 (90), species ± 696. *Vinca minor L., Periwinkle and *Plumeria rubra L., Frangipani, both widely cultivated ornamentals, have not been recorded as garden escapes

References:

• LEEUWENBERG, A.J.M. 1994. Taxa of the Apocynaceae above the genus level. In J.H. Seyani & A.C. Chikuni, Proceedings of the 13th plenary meeting AETFAT, 2. Malawi
• LIEDE, S. & ALBERS, F. 1994. Tribal disposition of genera of the Asclepiadaceae. Taxon 43
• STRUWE, L., ALBERT, V.A. & BREMER, B. 1994. Cladistics and family level classification of the GENTIANALES. Cladistics 10
• TAKHTAJAN, A. 1997. Diversity and classification of flowering plants. Columbia University Press, New York
• VENTER, H.J.T. & VERHOEVEN, R.L. 1997. A tribal classification of the Periplocoideae (Apocynaceae). Taxon 46

Resources:

• Classification of Apocynaceae
• Key to Apocynaceae Subfamilies
• Key to Apocynaceae Genera (Intermediate ranks omitted)

• Apocynaceae Subfamiles:

• Apocynaceae Genera: