4. Late Gzhelian (Carboniferous) to early Asselian (Permian) non-ammonoid cephalopods from the Taishaku Limestone Group, Southwest Japan

Abstract

The non-ammonoid cephalopod fauna described here was collected from the upper Gzhelianlower Asselian (Upper Carboniferous to Lower Permian) hydrozoan-algal buildups in the Taishaku Limestone Group, Southwest Japan. The fauna consists of four orthocerids : Michelinoceras? sp., Bogoslovskya miharanoroensis sp. nov., Geisonocerina? sp., Lopingoceras hayasakai sp. nov.; two nautilids : Parachouteauoceras bingoense gen. et sp. nov., Parachouteauoceras? sp.; and a bactritid : Bactrites sp. Parachouteauoceras is most similar to Chouteauoceras, but unlike the latter has a lobated aperture. The occurrence of Bogoslovskya miharanoroensis represents one of the latest records of the genus in the world. This fauna is important because it adds some new data to a poorly known Late Carboniferous-Early Permian non-ammonoid cephalopod fauna.