Tree up to 30 m. tall; trunk up to 2 m. or more diam., often strongly buttressed. Lvs rather thin, coriac., 20-40 × 15-25 mm., on petioles up to 4 mm. long; lamina glab. except on veins below, broad-ovate to ovate-oblong, coarsely, rather deeply sharply serrate with 6-8 pairs of teeth; venation distinct; fringed domatia 1-2 in basal vein axils. Staminate infls 1-8 per branchlet; peduncles glab., up to 4 mm. long, bearing 1-3 or rarely 5 subsessile fls. Per. 5 mm. long, campanulate; shallowly obtusely 5-lobed, sparsely to rather densely pubescent. Stamens 8-11; anthers 3 mm. long, red, yellow, or stramineous. Pistillate infls 1-5 per branchlet, sessile, ovoid to globose, 3 mm. long, glabrate, us. 3-fld. Lateral fls trimerous, terminal dimerous; stigmas ligulate, distinctly bilobed. Cupule pubescent, 4-partite; segs attenuate, up to 10 mm. long; glands between segs and bracts. Nuts 7 mm. long, triquetrous or flat; wings broad at base, attenuate.