Description from Flora of China
Quercus naiadarum Hance, J. Bot. 22: 227. 1884; Pasania naiadarum (Hance) Schottky; Q. neriifolia Seemen; Synaedrys naiadarum (Hance) Koidzumi.
Trees 4-10 m tall, glabrous except for inflorescences. Branchlets with a thin translucent wax layer. Leaf blade narrowly oblong to lanceolate, (5-)10-15(-30) × (0.7-)1-1.5 (-2.5) cm, rigidly papery, concolorous and without waxy scalelike trichomes, base attenuate and decurrent on a very short petiole, apex shortly acuminate and with a blunt tip; secondary veins 11-15 on each side of midvein, slender, evident; tertiary veins abaxially reticulate. Male inflorescences in a panicle; rachis densely tawny pubescent. Female inflorescences to 20 cm; rachis ca. 3 mm thick; cupules in clusters of ca. 3. Cupule discoid, 1.2-1.8 cm in diam., enclosing basal part of nut, outside puberulent, wall to 1 mm thick and ± woody near base; bracts usually connate into concentric rings, triangular, appressed. Nut broadly conical to rarely subglobose, 1-2 × 1.5-2.5 cm, apex pointed or flat; scar concave to almost flat. Fl. Jul-Aug, fr. Aug-Sep of following year.
* Frequent on stream banks; near sea level. Hainan