A Lower Permian mixed Boreal-Tethyan brachiopod fauna from the Nagaiwa-Sakamotozawa area, South Kitakami Belt, NE Japan

Three brachiopod species are described for the first time from the lowest part of the Sakamotozawa Formation (Sakmarian) of the Nagaiwa-Sakamotozawa area, South Kitakami Belt, northeast Japan. The specimens include two Boreal-type species, Waagenoconcha humboldti (d’Orbigny) and Rhynchopora sp., and a Tethyan-type species, Scacchinella sp. The occurrence of a mixed Boreal-Tethyan brachiopod fauna from the Lower Permian of the South Kitakami Belt suggests that the South Kitakami region was part of a continental shelf bordering the eastern margin of North China (Sino-Korea) during the Early Permian