Herbs, erect, creeping or climbing. Leaves opposite, sometimes cordate or hastate at base. Flowers axillary. Bracts 2, large, elliptic or ovate, enveloping the small calyx. Calyx usually of 10-18 linear teeth, rarely a small saucer-shaped body. Stamens 4, didynamous, 2-thecous; anthers opening by longitudinal slits. Retinacula 0. Ovary 2-locular, with 2 ovules in each loculus. Fruit a spherical beaked capsule. Distinguished by the large bracts, the calyx with its numerous lobes, the method of anther dehiscence and the beaked fruit.See Pseudocalyx for the differences with that genus. Derivation of name: Named after Carl Peter Thunberg (1743-1828) Worldwide: 90 species in the Old World tropics Zimbabwe: 5 cultivated taxa. Insects associated with this genus: |
|