chromosomes. The currently accepted view by systematic botanists is to place Nothofagus in its own family, Nothofagaceae. Subfamilies and genera Fagoideae K. Koch Fagus L.—beeches; about 10 to 13 species, north temperate east Asia, southwest Asia, Europe, eastern North America Quercoideae Õrsted Castanea Mill. 1754—chestnuts; eight species, north temperate east Asia, southwest Asia, southeast Europe, eastern North America Castanopsis (D. Don) Spach 1841—chinquapins or chinkapins; about 125–130 species, southeast Asia Chrysolepis Hjelmq. 1948—golden chinkapins; two species, western United States Lithocarpus Blume 1826—stone oaks; about 330-340 species, warm temperate to tropical Asia Notholithocarpus P. S. Manos, C. H. Cannon & S.H. Oh 2008 [2009]—Tanoaks; 1 species (formerly Lithocarpus densiflorus), endemic to California and southwest Oregon Quercus L. 1753—oaks; about 600 species, widespread Northern Hemisphere, crossing the equator in Indonesia Trigonobalanus Forman 1962—three species, tropical southeast Asia, Northern South America (Colombia) (three species of Colombobalanus and Formanodendron are included) The Quercus subgenus Cyclobalanopsis is treated as a distinct genus by the Flora of China, but as a subgenus by most taxonomists. The genus Nothofagus (southern beeches; about 40 species from the Southern Hemisphere), formerly included in the Fagaceae, is now treated in the separate family Nothofagaceae. Distribution The Fagaceae are widely distributed across the Northern Hemisphere. Genus-level diversity is concentrated in Southeast Asia, where most of the extant genera are thought to have evolved before migrating to Europe and North America (via the Bering Land Bridge). Members of the Fagaceae (such as Fagus grandifolia, Castanea dentata and Quercus alba in the Northeastern United States, or Fagus sylvatica, Quercus robur and Q. petraea in Europe) are often ecologically dominant in northern temperate forests. In tropical Southeast Asia, more than 400 species of Castanopsis and Lithocarpus are occur, with some species performing similar dominant roles over large areas. Systematics Modern molecular phylogenetics suggest the following relationships: Images References External links Fagaceae in Topwalks Family Fagaceae - diagnostic photos of many species at The Morton Arboretum Rosid families