A Taxonomic Revision of the Barbour’s Blue-tailed Skink <i>Plestiodon barbouri</i> (Reptilia: Squamata: Scincidae), With Descriptions of Three New Species

We herein provide a taxonomic revision of the species complex of Plestiodon barbouri (Van Denburgh, 1912) in the Ryukyu Archipelago, Japan. Molecular and morphological analyses showed that P. barbouri sensu lato comprised at least four distinct lineages, each warranting recognition as a separate species. Thus, we propose a new taxonomic arrangement, where we restrict P. barbouri sensu Van Denburgh to island populations of the Amami Group. In addition, we describe three new species for island populations of the Okinawa Group. The new species are distinguished from each other and all congeners by combining scalation and color patterns.