Asclepias
Erect herbs or shrubs; sap yellowish, milky. Leaves opposite or in whorls of 3, lacking glands at base of lamina, petiolate. Inflorescences of loose umbels, terminal or beside upper leaf axils, erect, long-pedunculate. Flowers pedicellate; sepals small, narrow; corolla deeply divided, lobes reflexed; gynostemium elongated, corona-lobes 5, at top of gynostemium, large, fleshy, spreading, saccate or boat-shaped, with an incurved horn arising from inner face; pollinia 2 per anther, pendent; style head broad, apex truncate, concave. Follicles elongate, smooth, erect, beaked; seeds many, with a silky coma.
About 100 species, in North and Central America; 1 species naturalised in Australia.
Members of the closely related Gomphocarpus are often included in Asclepias
Jeanes, J.A. (1999). Asclepiadaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 4, Cornaceae to Asteraceae, pp. 325–332. Inkata Press, Melbourne.
Spinning
