Phylogeny and historical biogeography of Acer

In order to reconstruct the robust phylogeny of Acer, I reanalyzed previously published chemical data including seed protein, leaf flavonoid, RFLP cpDNA and ITS nDNA and incorporated my own data on ITS nDNA, interspacers of psbA-trnH and trnL-F, intron of rp116 and coding gene of rbcL cpDNA. Three sectional groups of Acer were recognized from the ITS tree: (1)  Spicata-Palmata group: This includes Arguta, Cissifolia, Ginnala, Glabra, Macrantha, Negundo, Parviflora, and Spicata ; (2) Platanoidea group: This includes Lithocarpa, Macrophylla and Platanoidea; and (3)  Rubra group: This includes Acer, Goniocarpa, Hyptiocarpa, Indivisa, Integrifolia, Pentaphylla, Saccharina and Trifoliata .; Endemic areas with the genus Acer were determined by the method PAE (Parsimony Analysis of Endemicity), and five regions, i.e. eastern Asia (EAS), southern Asia (SAS), Europe and western Asia (Europe + WAS), western North America (WNAM) and eastern North America (ENAM) were recognized. Migration between the New World and the Old World was from Beringia via Alaska only and the early migration direction was from WNAM to EAS. Later on migration was from EAS to NAM (North America) and formed disjunctive patterns within section.; By integrating the fossil data and the phylogeny of Acer based on ITS nDNA, the possible evolutionary scenario of Acer could be described as follows. The lineage Acer could have originated in WNAM in the end of the Cretaceous about 67 million years ago (dated from ITS clock tree). It began to diverge about 60 million years ago during the late Paleocene and gave birth to Palmata-Spicata group and Platanoidea group. The Palmata-Spicata group was more diverse in the earlier history of the evolution of Acer. The extant sections of Palmata-Spicata group, including Arguta, Cissifolia, Ginnala, Glabra, Macrantha, Negundo, Parviflora, and Spicata, began to differentiate during the Eocene, which happened during the migration from WNAM to EAS. During the Eocene, Platanoidea began to differentiate into Lithocarpa and Macrophylla. (Abstract shortened by UMI.)...