Golden trumpet, brownbud allamanda

Shrubs sprawling. Leaves: pet­iole 0–2 mm, pubescent; blade oblanceolate, 50–150 × 15–40 mm, subcoriaceous, base atten­uate, margins often slightly revolute, apex cuspidate, sur­faces pubescent along midvein abaxially. Peduncles 10–40 mm, pubescent. Pedicels 4–6 mm, pubescent. Flowers: calyx lobes ovate to narrowly ovate, 10–12 mm, glabrous; corolla tube 20–35 × 2–3.5 mm, throat 20–40 × 15–25 mm, lobes spreading, obliquely ovate to suborbiculate, 12–35 × 10–40 mm. Capsules 4–5 × 3.5–4 cm. Seeds 13–22 mm. 2n = 18.

Flowering spring–fall; fruiting summer–fall. Ham­mocks, lakeshores, dunes, abandoned citrus groves and other disturbed sites; 0–20 m; introduced; Fla.; ne South America; introduced also in Mexico, Central America, and in tropical regions nearly worldwide.

Allamanda cathartica is native to northeastern South America (R. E. Woodson Jr. et al. 1970) but is widely cultivated and has escaped and become naturalized in both the New World and Old World Tropics. It is naturalized along much of the eastern coast of southern Mexico and Central America and has been reported to reach treelike proportions in Venezuela (T. J. Rosatti 1989). The globose capsules with spines to 15 mm are unique among the genera of Apocynaceae in the flora area.

The medicinal and toxic properties of Allamanda cathartica have been well documented. U. Quattrocchi (2012) reported that the latex may cause a contact dermatitis in sensitive individuals and severe catharsis on ingestion. An infusion of the leaves has been used as both an emetic and a purgative and has been demonstrated to have strong fungal toxicity against certain dermatophytes. According to G. E. Burrows and R. J. Tyrl (2013), the purgative effects result from the action of several types of iridoid compounds.