Description from
Flora of China
Guanabanus Miller.
Trees or shrubs, with an indument of simple or stellate hairs. Inflorescences terminal, leaf-opposed, extra-axillary, or sometimes cauliflorous, never axillary, 1-flowered or in few-flowered clusters. Pedicel usually short. Sepals 3, small, valvate. Petals 6, in 2 whorls or inner whorl rudimentary or absent, free or connate at base; outer petals valvate, fleshy but leathery when dry, connivent or somewhat spreading, inside basally concave, margin thick; inner petals imbricate or valvate. Stamens many; filament short; connectives apically convex or apiculate. Carpels many, often connate; ovule 1 per carpel, basal; styles clavate; stigmas muriculate. Fruit syncarpous, surface covered with knobs, bulges, spines, or less often smooth. Seeds many per syncarp, embedded in edible pulp.
Annona includes several trees that have become widely grown for their fruit.
About 100 species: mostly in tropical America, a few in tropical Africa; seven species (all introduced) in China.
(Authors: Li Bingtao (李秉滔 Li Ping-tao); Michael G. Gilbert)