Cheilostome Bryozoa from the Upper Cretaceous Himenoura Group, Kyushu, Japan

Abstract. Cheilostome bryozoans (Phylum Bryozoa; Order Cheilostomata) originated in the latest Jurassic but remained at low diversity until the late Albian–early Cenomanian, when they began an explosive radiation that has continued to the present day. Most knowledge of Late Cretaceous cheilostomes comes from Europe and the USA from deposits associated with the western Tethys Ocean. Only a few previous records of Cretaceous bryozoans exist from the margin of eastern Asia in the NW Pacific. We examined material from four localities of early– middle Campanian age in the Himenoura Group, Shimokoshikijima Island, Kagoshima Prefecture, southern Kyushu, Japan, and detected six cheilostome species but no cyclostomes. Two species were relatively common. For one of these, we erect the new genus Kenocharixa and describe a new species, Kenocharixa kashimaensis; we also transfer Charixa goshouraensis Dick, Komatsu, Takashima, and Ostrovsky and Conopeum stamenocelloides Gordon and Taylor to Kenocharixa. We describe the...