Description from Flora of China
Eugenia tetragona Wight, Ill. Ind. Bot. 2: 16. 1841; Syzygium nienkui Merrill & L. M. Perry.
Trees, to 20 m tall, d.b.h. to 15 cm. Branchlets stout, 4-angled, ridges conspicuous. Petiole 1-1.6 cm, stout; leaf blade leathery, elliptic to obovate, 12-18 × 6-8 cm, abaxially slightly pale when dry, adaxially dark brown and not glossy when dry, secondary veins 9-13 on each side of midvein and 7-10 mm apart, reticulate veins conspicuous, intramarginal veins 2-3 mm from margin, base broadly cuneate to rounded, apex rounded to obtuse and with a ca. 1 cm cusp. Inflorescences lateral on leafless branches, paniculate cymes, 3-5 cm. Flower buds 6-7 mm. Hypanthium short, obconic. Calyx lobes obtuse and short. Petals coherent, white. Stamens ca. 3 mm. Fruit tinged yellow, globose, ca. 1 cm in diam. Fl. (Feb-)Jul-Aug(-Nov), fr. Nov-Jan.
Open or dense broad-leaved evergreen forests, mountain valleys, steamsides; 800-2000 m. Guangxi, Hainan, Xizang (Cona, Mêdog), Yunnan [Bhutan, India, Myanmar, Nepal, Thailand].