Description from Flora of China
Xylopicrum P. Browne.
Trees [or shrubs]. Flowers axillary, solitary [or fasciculate]. Flower buds lanceolate [to subulate]. Pedicel usually short, bracteolate at apex [or base]. Sepals 3, valvate, thick, connate at base sometimes into a cup-shaped calyx. Petals 6, in 2 whorls, with each whorl valvate, connivent or scarcely open, elongated, thick, woody when dry, inside basally concave, middle narrowly convex; outer petals larger and longer than inner petals. Stamens many; anther locules oblong, extrorse, transversely septate; connectives 3-angular, apex truncate-dilated. Carpels few to many, free; ovules 2-6 per carpel, sutural; styles elongated; stigmas clavate [capitate, or oblong], extended. Fruit apocarpous; monocarps stipitate, oblong [to elongated], moniliform, often dehiscent. Seeds [1-]3-8[to many] per monocarp, ovoid; aril present but often inconspicuous.
About 160 species: Africa, America, SE Asia; one species in China.
(Authors: Li Bingtao (李秉滔 Li Ping-tao); Michael G. Gilbert)