A new genus and species of small bunodont artiodactyl (Mammalia), Myanmarius chitseini, is established on the basis of molar specimens from the upper middle Eocene Pondaung Formation, Myanmar. The specimens consist of upper molars and one m3. The m3 is provisionally referred to this species. Myanmarius is characterized by a low crown, bunodont cusps, a wide crushing trigon basin, a large metaconule, a reduced paraconule, a protocone distinctly larger than the other main cusps, an obtuse angled and inverted V-shaped centrocrista, a mesiodistally oriented postprotocrista and premetacristule, a buccally shifted and almost mesiodistally oriented cristid obliqua, no hypocone, no styles, and no lingual separation into two (mesial and distal) lobes of the upper molars. Our cladistic analysis supports the raoellid affinity of Myanmarius, which is nested with Khirtharia. However, if the m3 is excluded from the hypodigm of Myanmarius, the cladistic analysis rather supports the suoid affinity of Myanmarius. Therefore, the phyletic position of Myanmarius is still unclear.

Tanabeceras horokanaiense sp. nov. is described from the lowest Cenomanian (Upper Cretaceous) in the Horokanai area, Hokkaido, northern Japan. This new taxon, which represents an intermediate form between T. yezoense (Shigeta, 1996) and T. mikasaense (Shigeta, 1996), suggests that Tanabeceras evolved and radiated in the Northwest Pacific realm during the early Cenomanian. This evidence together with the presence of many endemic gaudryceratid ammonoids strongly suggests that there was something to separate distribution of the gaudryceratids between the Northwest Pacific realm and other regions during early Cenomanian time.

A radiolitid rudist, Eoradiolites cf. gilgitensis is described from a late early to late Aptian shallowmarine limestone block in the lower part of the Yezo Group, central Hokkaido, northern Japan. The Hokkaido Eoradiolites is characterized by a compact (non-cellular) outer shell layer, as seen in E. gilgitensis (from Iran, Afghanistan, Pakistan, and northern India), E. griesbachi (from Afghanistan), and E. ngariensis (from western Tibet in China), which are all located in the Southwest Asian region of the northern Tethyan margin. This is one of the earliest records in the world of primitive radiolitids with a radiolitiform myocardinal arrangement. This finding demonstrates that radiolitids had already expanded to the western Pacific at an early evolutionary stage, and that a faunal connection between the northwestern Pacific region and Southwest Asia existed at least in the late Aptian.

We describe a new species, Provanna urahoroensis sp. nov. from seep carbonates of the lower Oligocene Nuibetsu Formation in eastern Hokkaido, Japan. The new species is the second fossil record of Provanna from Paleogene rocks and resembles a smooth variant of the American Paleogene species, P. antiqua Squires, in having a smooth shell with very weak spiral cords. Based on its association with Bathymodiolus (s. l.), fossil Provanna including the new species possibly grazed preferably on bacteria on the surface of Bathymodiolus (s. l.) and of exposed carbonates.

A new species of well preserved zoroasterid asteroid was discovered from the lower Miocene Yamami Formation (approx. 16 Ma), Morozaki Group in Aichi Prefecture, central Japan. The specimens possess a small disc and long arms, and show clear stellate ossicles on the aboral disc surface, clearly supporting their placement within the genus Doraster. Currently Doraster is widely distributed in bathyal depths in the western Atlantic, represented only by one modern species, D. constellatus. The new discovery of fossil Doraster species not only extends the stratigraphic range of this genus but also suggests it was widely distributed in the Pacific before the closure of the Isthmus of Panama.