1. Protium N. L. Burman, Fl. Indica. 88. 1768.
马蹄果属 ma ti guo shu
Small trees. Branchlet pith without vascular strands. Leaves odd-pinnate, alternate, exstipulate; leaflets with petiolule, apex cuspidate. Flowers in axillary or terminal panicles, unisexual, bisexual, or polygamous. Calyx cupular or campanulate, shallowly 4- or 5-lobed, lobes imbricate in bud, recurved, persistent but not enlarged in fruit. Petals 5, valvate, apex incurved in bud, later recurved. Stamens as many as or 2 × as many as petals or more, distinct, inserted outside of disk, reduced in females but probably fertile; disk fleshy and thick, glabrous, flattened in male flowers, annular or cupular in female or bisexual flowers, grooved; filaments glabrous. Ovary 4- or 5-celled, glabrous or pubescent, globose or ovoid, reduced in male flowers; ovules 2 in each cell; style short or long; stigma capitate or shallowly 4- or 5-lobed. Drupe globose, ovoid, or somewhat compressed, apex with rudiment of style; pyrenes 4 or 5 (some often degenerated), rarely 1 or 2, bony with thin coat; cotyledons folded, palmate.
About 90 species: mostly in tropical America, the rest scattered in all parts of tropical Asia; two species (one endemic) in China.