Castanopsis mekongensis A. Camus

Trees; young shoots, petioles, leaf blades abaxially, and rachis of inflorescences densely pubescent. Petiole 1-2 cm; leaf blade ovate-elliptic, broadly elliptic, or sometimes ovate, 15-25 × 5-8 cm, thickly papery to leathery, abaxially grayish, adaxially dark black-brown when young, grayish brown to yellowish gray when dry, puberulent on midvein, base rounded to acute and symmetric or inaequilateral, margin entire, apex acuminate; midvein and secondary veins adaxially usually impressed; secondary veins 12-16 on each side of midvein. Infructescence ca. 10 cm or rarely longer. Cupule globose, 5-6 cm in diam., wall ca. 2 mm thick; bracts spinelike, entirely covering cupule, 1-1.5 cm, sparsely pubescent, base connate into bundles. Nut 1 per cupule, oblate, 1.3-1.6 × 1.5-2 cm, densely pubescent; scar covering ca. 1/3 of nut. Fl. Mar-Apr, fr. Aug-Oct of following year.

S to SE Yunnan [Laos]

Broad-leaved evergreen forests; 600-2000 m.

Castanopsis fohaiensis Hu; C. lantsangensis Hu; C. wangii Hu & W. C. Cheng.