Description from Flora of China
Blastus yunnanensis H. L. Li (1944), not H. Léveillé (1912).
Shrubs 1.5-2 m tall. Stems subterete but 4-sided when young, densely glandular, glabrescent. Petiole 2-6 cm, densely glandular; leaf blade lanceolate to rarely elliptic, 8-15 × 2.5-4.2 cm, papery to submembranous, abaxially glandular, adaxially sparsely puberulous when young but glabrescent, secondary veins 1(or 2) on each side of midvein, base cuneate, margin entire or inconspicuously denticulate, apex acuminate. Inflorescences axillary, umbellate, 3-5-flowered; peduncle very short to nearly absent. Pedicel ca. 2 mm, glandular. Hypanthium campanulate-funnelform, ca. 5 mm, glandular. Petals 4, pink to reddish lavender, oblong-ovate, 4-4.5 mm, inclined to one side, both sides near margin pellucidly glandular, apex acuminate. Stamens 4; filaments ca. 2.5 mm; anthers ca. 4 mm, slightly curved; connective minutely inflated, extended from base of anthers. Ovary inferior, ovoid, 4-celled, glandular. Fl. Jun, fr. unknown.
● Dense mixed forests, valleys, stream banks, moist places; 800-1300 m. SE Yunnan.