Description from Flora of China
Trees or shrubs, small to medium-sized, evergreen or deciduous. Leaves alternate, 3-veined from base, margin subentire to serrate; stipules usually changed into 1 or 2 lignified, erect or revurved spines. Flowers bisexual, 5-merous, perigynous, few to many in axillary, pedunculate cymes. Pedicel short, often elongated in fruit. Calyx tube hemispheric to dish-shaped; sepals free, deltoid, 1.5-2.5 × 1.5-2.5 mm, abaxially ± pubescent to glabrous, adaxially keeled, apex acute to weakly acuminate. Petals spatulate or unguiculate,1-2 mm, often enfolding stamens. Stamens free, 1.5-2 mm; filaments subulate, thin; anthers ovoid, latrorse. Disk adnate with calyx tube, pentagonal or rounded, thick, fleshy, glabrous. Ovary semi-inferior, 2- or 3-loculed, with 1 ovule per locule, slightly immersed in disk; style cylindric or flattened, with 2 or 3 ± diverging stylar branches. Fruit a dry, indehiscent, disk- to cup-shaped or hemispheric, winged drupe, base ± distinctly conical, often with remains of calyx tube, apex rounded to ± flattened; mesocarp leathery to corky; endocarp lignified. Seeds brownish, shiny, obovoid to ovoid; endosperm scanty, cotyledons flat.
Five species: E Asia, Europe; five species (three endemic, one introduced) in China.