Scientific name: Cryptostegia grandiflora Roxb. ex R.Br.

Family: Apocinaceae

Common name: Rubbervine

This climber is a very vigorous evergreen shrub; it grows semi-erect and readily covers any support, and can even choke nearby trees. It is native to south-western Madagascar, where it grows near watercourses. It has become established in many tropical areas, such as India and the Caribbean; in Australia, it is considered an invasive species.

The stems of Cryptostegeia are cylindrical, with a few lenticels. Its leaves are between 4 and 10 cm long. They are elliptical, tapering at the ends, with entire margins; they are bright green and glabrous, that is, without hairs. The fruit consists of two woody, boat-shaped follicles, each containing many hairy seeds. The flowers are a beautiful purplish colour and funnel-shaped. They are hard to miss, as they measure between 4 and 6 cm; hence the species’ name, grandiflora. The genus name derives from the Greek words kryptos, meaning ‘hidden’, and stego, meaning ‘to cover’, referring to the fact that the stamens are covered by a crown of scales.

All parts of the plant are toxic, so care must be taken with the latex that is released when it is cut or handled. In some places it has been introduced for commercial reasons, as the latex produces high-quality rubber, but this is no longer profitable, so these abandoned crops have led to its spread. In La Concepción, it covers one of the arches with climbing plants in the Garden of the Senses.