Description from Flora of China
Trees or shrubs, deciduous. Branches unarmed or spiny. Axillary winter buds (2 or)3, lateral ones flower buds, central one a leaf bud; terminal winter buds present. Stipules present. Leaves simple, alternate, sometimes fascicled on short branchlets, conduplicate when young; petiole usually with 2 nectaries or sometimes nectaries at base of leaf blade margin; leaf blade margin often serrate. Inflorescences borne on axillary short branches, 1(or 2)-flowered. Flowers bisexual, regular, opening before or rarely with leaves. Pedicel nearly absent or short, rarely long. Hypanthium caducous in fruit. Sepals 5, imbricate. Petals 5, pink or white, inserted on rim of hypanthium, imbricate. Stamens 15 to many, inserted with petals; filaments filiform, free. Ovary superior, hairy, 1-loculed; ovules 2, collateral, pendulous. Style terminal, elongated. Fruit a drupe, hairy, glabrous in some cultivated Amygdalus persica, with a conspicuous longitudinal groove; mesocarp fleshy and not splitting or dry and splitting when ripe; endocarp hard, 2-valved, globose or ellipsoid, usually compressed, surface furrowed, pitted, rugose, or smooth.
Many species and cultivars are grown for their edible fruit or as garden ornamentals, and a few species are also grown for their edible seeds.
About 40 species; C, E, and SW Asia, S Europe; 11 species (four endemic, one introduced) in China.
(Authors: Lu Lingdi (Lu Ling-ti); Bruce Bartholomew)