Mud shrimp associated with burrows from the Oligocene Ashiya Group, northern Kyushu, Japan, with description of a new species of Upogebia (Decapoda: Gebiidea)

Upogebia hibiki sp. nov. (Gebiidea: Upogebiidae) is described from the Oligocene of northern Kyushu, Japan. The new species closely resembles U. mizunamiensis Karasawa 1989, but differs in having an arched ridge on the dorso-distal mesial surface of the palm of pereiopod 1. Additionally, the new species has a triangular rostrum and a narrow gastric region. The specimens are associated with fossil burrows assigned to the ichnogenus Psilonichnus Fursich, 1981. Therefore, Psilonichnus described herein is thought to be formed by U. hibiki sp. nov.