Resolving the higher-order phylogenetic relationships of the circumtropical Mabuya group (Squamata: Scincidae): An out-of-Asia diversification.

Abstract Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of the Mabuya group, the intergeneric relationships have remained difficult to resolve. The most-persistent unresolved regions of the phylogeny of the group include: (1) the placement of the Middle-Eastern Trachylepis with respect to the Afro-Malagasy Trachylepis and its taxonomic status; (2) the phylogenetic position of the Cape Verdean Chioninia within the larger Mabuya group; (3) support for the placement of Dasia with respect to the entire group; and (4) the phylogenetic placement of Eutropis novemcarinata with respect to other Eutropis and Dasia . In this study, we include representatives of all these taxa as well as African Eumecia and Neotropical Mabuya . We seek to address these phylogenetic and systematic issues by generating a well-resolved and supported phylogeny for the Mabuya group as a whole that can be used to develop a stable taxonomy and reconstruct the geographic patterns of diversification within the group. To meet these goals, we built a large multi-locus dataset of 11 markers (nine nuclear and two mitochondrial), and performed concatenated and species tree analyses to generate a well-supported phylogeny for the group. Statistical topology tests reject the monophyly of Middle-Eastern Trachylepis with Afro-Malagasy Trachylepis , and to reflect monophyly we place the Middle-Eastern species into a previously described genus, Heremites . Cape-Verdean Chioninia are resolved as the strongly supported sister-group to Afro-Malagasy Trachylepis . Monophyly of the Southeast-Asian genera, Eutropis and Dasia , is not supported, with a clade composed of Dasia  +  Eutropis novemcarinata more closely related to the rest of the Mabuya group than to the remaining Eutropis . The phylogenetic position of E . novemcarinata renders Eutropis polyphyletic, and we therefore describe and place E . novemcarinata into a new monotypic genus, Toenayar , to preserve monophyly among the genera. In light of these novel findings, we review and discuss the historical biogeography of the entire Mabuya group.