Vertebrate diversity of the early cretaceous tetori biota from Japan, the state of the art

The comprehensive list of vertebrate skeletal fossils (excluding ichnofossils) from the Early Cretaceous Tetori Group is provided. Numbers of species of selected vertebrate taxonomic groups of the Tetori Group are compared with those from several famous Late Jurassic–Early Cretaceous Lagerstätten to evaluate the vertebrate diversity of the Tetori Biota. Vertebrate fauna of the Tetori Group is characterized by the presence of a tritylodont synapsid, that of both diversified choristoderes and a crocodyliform, remarkably high diversity of the testudines, moderate diversity of mammals, squamates and dinosaurs, and possible low diversity of fish. Most of the vertebrate taxonomic groups recognized in other fauna/biotas are present in the Tetori Biota. The vertebrate diversity of the Tetori Biota can be considered to be comparable to those of the Late Jurassic–Early Cretaceous Lagerstätten at present, and is expected to be higher in the near future. Further investigation and comparison of vertebrate diversities in almost coeval strata in several regions in East and Southeast Asia probably provide the useful information to reveal the paleo(bio)geographical and palaeoclimatic reconstruction in Asia, and also the evolution of the Mesozoic terrestrial ecosystem.