Asclepias
Source:
SSA
Description:
Perennial or annual herbs or shrubs with milky sap. Leaves opposite or whorled, usually sessile. Flowers in pedunculate or occasionally sessile umbels, lateral at nodes and terminal. Sepals usually with scales within base. Corolla rotate, tube very short, deeply 5-lobed. Corona of 5 lobes arising from near base of staminal column; lobes erect or radiating, laterally compressed, cucullate or compressed-cucullate or with a fissure down inner face, sometimes with 1(2) horns or other process within cavity and rarely with a dorsal lobule or reflexed horn. Anthers 2-locular, with terminal, membranous, incumbent or erect appendage. Pollinia pendulous, ellipsoidal; caudicles shorter than pollinia. Follicles usually solitary by abortion, globose to fusiform, smooth or with processes on surface. Seeds brownish, oblong, convex on back and concave on face, or flattened and narrowly winged, usually with protuberances, with tuft of hairs at micropylar end. x = 11 (10, 12).
Distribution:
Species +/- 150, Africa, Arabian Peninsula, America; +/- 50 in sthn Afr., widespread. Note: Trachycalymma pulchella is recognised as Asclepias pulchellum, but the remainder of the genus which occurs outside the FSA region, is retained in Trachycalymma (K.Schum.) Bullock.