In the New World there are 350 spp. from Fagales in 22 genera, being 239 Fagaceae in Castanea (3), Chrysolepis (2), Colombobalanus (1), Fagus (1), Lithocarpus (1) and Quercus (231); 38 Juglandaceae in Alfaroa (5), Carya (13), Juglans (17) and Oreomunnea (3); 34 spp. of Betulaceae in Alnus (10), Betula (17), Carpinus (2), Corylus (2) and Ostrya (3); 28 Myricaceae in Comptonia (1), Myrica (17) and Morella (10); 10 Nothofagaceae in Fuscospora (1), Lophozonia (4) and Nothofagus (5); and one Ticodendraceae in Ticodendron (1).
For comparison, China has 404 spp in this order, (7/)291 spp. from Fagaceae, (6/)89 sp. from Batulaceae, (7/)20 spp. from Juglandaceae and (1/)4 spp. of Myricaceae (Flora of China).
Almost 2/3 of New World Fagales are Quercus (231), and almost a half are Mexican Quercus (137). Mexico has 162 spp., c. 84% only Quercus. Mexico has 128 Myrtaceae. Brazil has 1,153 spp. in this family. Brazil has 3.5✕ more Myrtaceae than the sum of all Myrtaceae and Fagales in Mexico.
America Latina is one of the centers of Fagaceae distribution, at least for the genus Quercus. There are a total of 145 Fagaceae species native to America Latina of which 143 are Quercus, with the other two being one species of Fagus and one species of Trigonobalanus. Within Quercus, 32 species that occur in America Latina extend into the U.S.A. and one, Q. muehlenbergii, ranges as far north as Canada. By far the main center for Quercus in America Latina is Mexico (137 spp. of which 83 are endemic); the number of species rapidly falls off in Central America, and only one species (Q. humboldtii) occurs in South America (Colombia), in Bartholomew & Almada (Phytotaxa, 2023).
U.S.A. has 151 Fagales, being 96 Fagaceae, 30 Betulaceae, 17 Juglandaceae and 8 Myricaceae. Brazil has, only in Myrcia, 3✕ more species tham all Fagales from U.S.A.