Description from Flora of China
Shrubs, subshrubs, or small trees, deciduous, rarely evergreen, armed, rarely unarmed; buds ovoid or subglobose. Leaves simple, stipulate, venation craspedodromous, margin serrate and lobed or partite, rarely entire. Inflorescences corymbose, sometimes flowers solitary. Hypanthium campanulate. Sepals 5. Petals 5, white, rarely pinkish. Stamens 5–25; carpels 1–5, connate, but free apically. Ovary inferior or semi-inferior, with 2 ovules per locule, but one rudimentary. Fruit a pome, with persistent sepals at apex; carpels bony when mature, each locule with 1 seed; seed erect, cotyledons plano-convex.
Crataegus biloba H. Léveillé, described from Guizhou, is Symplocos paniculata (Thunberg) Miquel in the Symplocaceae (see Fl. China 15: 252. 1996), under which it has been recognized as f. biloba (H. Léveillé) Rehder. Crataegus lyi H. Léveillé (Fl. Kouy-Tcheou, 347. 1915), also described from Guizhou, is the same species.
At least 1000 species: N temperate regions, especially abundant in North America; 18 species (ten endemic) in China.
(Authors: Gu Cuizhi (Ku Tsue-chih); Stephen A. Spongberg)