A new species of the genus Amia of the family Amiidae, A. godai is described based on a parasphenoid and many isolated bones and scales found from the Early Miocene Nakamura Formation of the Mizunami Group along the Kiso River in Kani City, Gifu Prefecture, Central Japan. Amia godai sp. nov. is distinguished by having a V-shaped edentulous area in the posterior part of the tooth patch of the parasphenoid. This is the first record of the genus from the Early Miocene in the world and the first record of the family from the Cenozoic in Japan.

A new specimen of the Early Pliocene porpoise Haborophocoena toyoshimai, comprising an incomplete cranium, was discovered from the Embetsu Formation near the locality of H. minutus, Haboro Town, Hokkaido, Japan. The specimen is a juvenile skull of H. toyoshimai, comparable in size to the congeneric H. minutus. It confirms and/or adds some characters that define H. toyoshimai. It is now clear that the structure of the posterior part of the palate is unique to H. toyoshimai among phocoenids. It is markedly deep dorsoventrally at the level of the midlength of the orbit. In ventral view, the palatal face of the pterygo-palatine complex is distinct in having a sharp and sinuous lateral edge. The palatal surface of the pterygo-palatine complex is gently concave. A prenarial triangle anteromedial to the premaxillary eminence is depressed. The new specimen also reveals possible ontogenetic variation.

Sixty-two podocopid ostracod species belonging to 37 genera were identified during the analysis of 57 samples from the Miocene Itahana Formation (ca. 11.0 to 10.5 Ma) in the Tomioka district, Gunma Prefecture, central Japan. Two assemblages were recognized in the lower member of the Itahana Formation: Assemblage I is characterized by Aurila joushuensis, Loxoconcha nozokiensis, Paracytheridea neolongicaudata, Callistocythere spp., and Cythere omotenipponica; Assemblage II is characterized by Krithe sp., Acanthocythereis sp., Ambtonia takayasui, Ambtonia tamayuensis, and Argilloecia sp. Assemblage II indicates a depositional environment of muddy bottoms in the upper bathyal open sea, while for the species of Assemblage I a habitat of sandy bottoms in warm shallow open seas is indicated, suggesting that the depositional environment of the lowermost Itahana Formation was bathyal and that the ostracods of Assemblage I were transported to that environment by turbidity currents. Fifteen new species are described in this study.

A new Cretaceous heteromorph ammonoid, Phylloptychoceras horitai sp. nov., is described from the lowest Maastrichtian of Hokkaido, Japan. Its shell is ornamented with very weak, broadly rounded ribs and its suture line is characterized by a deeply incised, trifid dorsal lobe and three bifid lateral saddles with minor indentations. This occurrence suggests that Phylloptychoceras evolved in the North Pacific during late Campanian or early Maastrichtian time and then achieved worldwide distribution during late Maastrichtian time.

Little is known about Ordovician litho- and biostratigraphy in northern and western Thailand because outcrops are scarce in these mountainous areas. Biostratigraphic and biogeographic studies of conodonts are limited to the uppermost Floian to lower Darriwilian strata in western Thailand. This paper describes and discusses a new Middle Ordovician conodont fauna that includes nine species from the Thong Pha Phum area of western Thailand. This is the first report of Eoplacognathus suecicus, Pygodus lunnensis, Protopanderodus calceatus, Protopanderodus cooperi, and Protopanderodus graeai in Thailand and indicates that a cool-water fauna existed in western Thailand and in southern peninsular Thailand during the Middle to Late Ordovician. The Dapingian to early Darriwilian sea-level rise likely resulted in an immigration of this “cooler or deeper water” fauna to the Thong Pha Phum area.

Many species of the family Echinorhinidae are reported from the Cenozoic, but from the Cretaceous only a few species have been reported. In this paper, a new species, Echinorhinus wadanohanaensis of the family Echinorhinidae, is described from the Upper Cretaceous (Santonian) Hinoshima Formation of the Himenoura Group at Ryugatake-machi in Kumamoto Prefecture, Japan. The species differs from other congeners in having a distally inclined main cusp, the distally directed cusp apex not extending beyond the distal demarcation of the distal heel, no lateral cusplets (basal cusplets), a large principal cusp, no vertical groove in the root, few grooves below the boundary of the enameloid on the lingual face, and being markedly large in size. This is the first report of the family Echinorhinidae from the Santonian as well as the first report of the family Echinorhinidae from the Cretaceous of Japan.