Desquamatia ( Seratrypa ) from the Upper Devonian Choanji Formation in the South Kitakami Belt, Japan, and its stratigraphical significance

Abstract

The Choanji Formation is newly defined as an Upper Devonian (Frasnian ‒ Famennian) sandstone- and shale-dominanted formation, in the Choanji area, South Kitakami Belt, northeastern Japan. The Late Devonian brachiopods, Desquamatia ( Seratrypa ) and Cyrtospirifer occur within the middle and upper parts of the Choanji Formation, respectively. The former is described for the first time in Japan.