Description from Flora of China
Castanopsis lunglingensis Hu.
Trees 20-27 m tall. Branches glabrous; young shoots dark purplish red, dark brown when dry. Petiole 1.5-2 cm; leaf blade oblong, narrowly elliptic, or sometimes oblanceolate, 15-25 × 4-7 cm, papery, abaxially with a tight and thin layer of scalelike trichomes, base cuneate and oblique, margin entire, apex acute to acuminate; midvein and secondary veins adaxially slightly raised; secondary veins 14-17 on each side of midvein. Male inflorescences ca. 20 cm; rachis sparsely puberulent. Female flowers 3 per cupule. Infructescence rachis glabrous, 5-8 mm thick, fruit loosely arranged. Cupule subglobose to broadly elliptic, 4-5 cm in diam., outside glabrescent, dark brown when dry, wall 2-3 mm thick; bracts spinelike, entirely covering cupule, 1-1.5 cm, base connate into bundles. Nuts 2 or 3 per cupule, broadly conical, ca. 1.2 cm in diam., densely hairy; scar covering ca. 1/3 of nut. Fr. Oct-Nov.
Mixed and broad-leaved evergreen forests; below 2100 m. S and W Yunnan [Thailand, Vietnam]