Description from Flora of China
Cyclobalanopsis bambusifolia (Hance) Chun ex Y. C. Hsu & H. W. Jen; Quercus bambusifolia Hance (1875), not Fortune (1860) nor T. M. Masters (1874); Q. neglecta (Schottky) Koidzumi.
Trees to 20 m tall. Branchlets grayish brown sericeous, glabrescent. Leaves crowded toward branchlet apex; petiole 2-5 mm, glabrous; leaf blade narrowly lanceolate to elliptic-lanceolate, 3-11 × 0.5-1.8 cm, subleathery, abaxially whitish and glabrous or basally villous, base cuneate, margin entire or indistinctly 1- or 2-crenate toward apex, apex rounded; midvein adaxially slightly raised or flat; secondary veins 7-14 on each side of midvein, inconspicuous; tertiary veins abaxially inconspicuous to obscure. Female inflorescences 5-10 mm, rachis grayish brown tomentose when young; cupules 2-many. Infructescences 5-10 mm, usually 1-fruited. Cupule saucer-shaped to cupular, 5-10 mm × 1.3-1.5(-1.8) cm, covering base of nut, outside grayish brown velutinous, inside brown tomentose, wall ca. 1 mm thick; bracts in 4-6 rings, margin entire or triangular denticulate. Nut obovoid to ellipsoid, 1.5-2.5 × 1-1.6 cm, puberulent, glabrescent; scar 5-7 mm in diam., slightly convex; stylopodium persistent, evident. Fl. Feb-Mar, fr. Aug-Nov.
Dense forests in mountains; 500-2200 m. Guangdong, Guangxi, Hainan [Vietnam]