Description from Flora of China
Trees, deciduous. Branchlets never spinose, never corky or winged. Stipules 2, free, linear-lanceolate, caducous, leaving a short transverse scar on each side of leaf base. Leaves distichous, margin serrate to crenate; venation pinnate; secondary veins extending to margin, each ending in a tooth. Flowers appearing at same time as leaves, polygamous. Male flowers: clustered in proximal leaf axil of young branchlets. Perianth campanulate, 4-6(or 7)-lobed. Stamens equal in number to perianth lobes; filaments short, erect. Female and bisexual flowers: usually solitary or rarely 2-4-clustered in distal leaf axil of young branchlets. Perianth 4-6-parted, tepals imbricate. Staminodes absent or rarely developed. Ovary sessile; ovule pendulous, slightly amphitropous. Style excentric. Drupes oblique, dorsally keeled; endocarp hard; perianth persistent; stigmas beak-shaped. Seed slightly compressed, apex concave; endosperm absent; embryo curved; cotyledons broad, apically slightly notched to 2-lobed. 2n = 28.
We are following traditional usage in referring to the fruits as drupes. The exocarp is green but not fleshy, and the fruit resembles the samara of Hemiptelea but has no wing.
Five species: E and SW Asia, SE Europe; three species (two endemic) in China.