Thunbergia alata Bojer ex Sims

  • Authority

    Acevedo-Rodríguez, Pedro. 2005. Vines and climbing plants of Puerto Rico and the Virgin Islands. Contr. U. S. Natl. Herb. 51: 1-483.

  • Family

    Acanthaceae

  • Scientific Name

    Thunbergia alata Bojer ex Sims

  • Description

    Description - Herbaceous vine, creeping or climbing, twining, 2-3 m in length. Stems cylindrical, slender (ca. 2 mm), puberulous. Leaves opposite; blades 4.5-10.5 x 3.2-6 cm, ovate, lobed, chartaceous. the apex acute, the base subcordiform; upper surface dark green, dull, pubescent; lower surface pale green, dull, with prominent venation; petioles 4-8 cm long, winged, pubescent. Flowers axillary, solitary; pedicels pubescent, 4-5 cm long; bracts green, ovate, pubescent, 1.5 cm long, covering the calyx and the corolla tube. Calyx yellowish green, with 12 filiform lobes, ca. 4 mm long; corolla orange, pale yellow, or less frequently whitish, infundibuliform, with 5 lobes, the tube ca. 2.5 cm long, narrow at the base, dark violet inside, the lobes ca. 2.5 cm long with the apex truncate, the limb ca. 5 cm in diameter; stamens with glandular hairs on the basal portion. Capsules ca. 4 mm long, depressed-globose to 4-lobed at the base, the upper half in the form of a beak, dehiscent by two valves; seeds 2 or 4, 1.2-1.5 mm long, semicircular, reticulate.

    Phenology - Flowering sporadically throughout the year.

    Conservation Status - Exotic, very common, naturalized in Puerto Rico.

  • Common Names

    Susana, viuda, black-eyed Susan, clock vine