Middle Carboniferous orthoconic cephalopods from the Omi Limestone Group, Central Japan

Abstract

A Middle Carboniferous (probable late Bashkirian) fauna of orthoconic cephalopods was collected from bioclastic rudstone/grainstone in the Omi Limestone Group, Central Japan. This fauna belongs to the Taishaku-Akiyoshi-South China Faunal Province. Recognized herein are the orthocerid nautiloid Bogoslovskya omiensis sp. nov., the bactritids Bactrites nagatoensis Niko, Nishida and Kyuma, 1991 and Bactrites sp., and an indeterminate body chamber. This is the first reliable documentation of orthoconic cephalopods from the Omi Limestone Group.