Bredia hainanensis Merrill & Chun, Sunyatsenia 6: 145. 1940; Plagiopetalum hainanense (Merrill & Chun) Merrill ex H. L. Li.

Shrubs 30-50 cm tall, many-branched. Stems grayish white, obtusely 4-sided; branchlets 4-sided, puberulous and with sparse glandular trichomes. Petiole 0.5-2 cm, puberulous and with sparse glandular trichomes; leaf blade oblong-elliptic, elliptic, or ovate, 3-7 × 1.5-3.5 cm, papery, abaxially puberulous and shortly setose, adaxially with a sparse line of setose trichomes between veins but otherwise glabrous, secondary veins 2 or 3(or 4) on each side of midvein, base broadly cuneate to subround, margin denticulate, apex acute to obtuse. Inflorescences terminal, cymose contracted to becoming subumbellate, 4-5 × ca. 3 cm; peduncle 2.5-3 cm, puberulous and with glandular trichomes. Pedicel 6-7 mm, puberulous and with glandular trichomes. Hypanthium funnel-shaped, ca. 4 mm, 4-sided, puberulous and with glandular trichomes. Calyx lobes shortly triangular, ca. 1 mm, apex acute. Petals pink to purplish red, obovate, 8-11 × 6-8 mm, oblique, apex apiculate. Stamens 8, ca. 8 mm, equal; anthers lanceolate, ca. 4 mm; connective decurrent, forming a short spur, abaxially inconspicuously tuberculate. Ovary ovoid, apical margin with glandular trichomes. Capsule cup-shaped, ca. 4 × 4 mm, 4-sided; hypanthium exceeding capsule, 8-ribbed; calyx lobes puberulous and with sparse glandular trichomes. Fl. May-Aug, fr. Aug-Dec.

● Forests, mountain slopes, limestone, hillsides, stream banks; 600-800 m. Hainan.