Trees or rarely shrubs, mostly monoecious, deciduous or evergreen; buds enclosed by scales. Leaves alternate, spiral, simple, petiolate, gland-dotted; margin crenate, toothed, or shallowly lobed; stipules peltate or basally attached. Inflorescences of short axillary, bracteate, mostly 3-flowered dichasia, the central flower sometimes abortive. Perianth a single connate, usually 6-lobed whorl. Flowers unisexual; male flowers sessile or shortly pedunculate, stamens 4–90; female flowers above the males, subtended by an involucre of 4-ranked bracts, these later forming a cupule around the fruits; ovary inferior, of usually 3 carpels, each with its own style. Fruit a cupule containing a central 2-winged nut and 2 lateral 3-winged nuts.

1 genus, c. 35 species. Confined to the southern hemisphere: Papua New Guinea, Solomon Islands, New Zealand, SE  Australia and South America.

Previously in Fagaceae.

Created by: Val Stajsic

Updated by: Val Stajsic, March 2018