Fibrous-rooted annual. Stems twining, with retrorse hairs, tawny hirsute when young, otherwise smooth. Petioles long, sometimes > lamina, with retrorse hairs. Lamina 5-16-(18) × 4.5-11-(13) cm, broad-ovate, entire or nearly so, occasionally with lobes near base, with appressed hairs at least on veins; base cordate with rounded sinus; apex acute or abruptly acuminate. Cymes axillary, few-flowered; peduncles 5-10 cm long with dense retrorse hairs; pedicels variable but < peduncles, with dense retrorse hairs. Bracts narrow-linear, < pedicels. Calyx 1.3-1.6 cm long; sepals oblong-lanceolate, acute, the lower part densely covered with stiff and bulbous-based hairs. Corolla c. 5 cm long and 5-6 cm diam. across limb, funnelform; basal part of tube pink; remainder of corolla violet-purple except for dark reddish purple mid-petaline bands. Stamens included, the longest c. 2.5 cm long; filaments hairy towards base. Style > stamens. Capsule globular, glabrous; beak inconspicuous. Seeds < 7 mm long, glabrous, dark.