Fourteen species of early Permian (Artinskian and Kungurian) fusulines are described from the upper part of the Nakadaira Formation in the Kamiyasse area, South Kitakami, Japan, correlatable to the upper part of the Sakamotozawa Formation in the type area. Among them, Praeparafusulina pseudojaponica, Juresanella juresanensis, and Juresanella uralensis diagnostic in the Nakadaira Formation are uncommon or absent in seamount-originated limestones of the Permian and Jurassic terranes of Japan, and important paleobiogeographically. Darvasella kitakamiensis sp. nov. is distinguished from the known species of the genus by its more regularly folded septa and the presence of axial fillings. Based on these fusulines, the uppermost part of the Nakadaira Formation is correlated to the Artinskian/Kungurian of Cisuralian, suggesting that the carbonate facies having early and most middle Guadalupian fusulines is not developed in the Kamiyasse area, as well as probably throughout the southern Kitakami.

Recent molecular analyses have challenged the traditional classification of scleractinian corals at almost all taxonomic levels, suggesting a requirement of new morphological characters for classification. Microskeletal characters have shown great potential to support the classification of the molecular-based clades of the scleractinian corals. Flabellum (Family Flabellidae) is the fifth largest genus and contains two subgenera, F. (Flabellum) and F. (Ulocyathus). The genus is very important in deciphering flabellid evolution, as phylogenetic relationship is still ambiguous in this family. In particular, little is known of the microstructural features of Flabellum species. Here we discuss the microskeletal structures of F. (F.) magnificum and F. (U.) deludens. Rapid accretion deposits (RADs) on the walls of F. (F.) magnificum show dome-shaped strands ca. 50–100 µm wide, which are composed alternatively of microcrystalline and fibrous parts. In contrast, the RADs on the walls of F. (U.) deludens consist of strands (50–100 µm long and 20–30 µm wide) made up of very short fibers (ca. 0.5–5 µm long) or microcrystallines with meniscus structure and dome-shaped fibrous layers. Thickening deposits (TDs) on the walls of both species are characterized by three qualities: (1) layered bundles consisting of fibrous crystals; (2) shingle-like TDs composed of small crystals and microcrystallines; and (3) shingle-like TDs comprised of larger fibers. In particular, in F. (U.) deludens, the TD of the calicular side of the wall is mainly formed of shingle-like TDs. The walls of F. (U.) deludens and F. (F.) magnificum thus differ completely in terms of the RAD (digitated strand and dome-shaped fibrous layers vs. continuous dome-shaped alternation) and TD characteristics. These kinds of microskeletal differences could support the molecular phylogenetic distinction between the F. (U.) spp. cluster and the F. (F.) clusters.

The age of the primitive ichthyopterygian Thaisaurus is more accurately defined due to the discovery of a new species of the ammonoid genus Marcouxia from beds about 2.4 m below the horizon from which the holotype of Thaisaurus chonglakmanii was collected in the Phukhaothong Dolomite Member of the Chaiburi Formation in the Phatthalung area, southern Thailand. The shell of Marcouxia chaiburiensis sp. nov. is characterized by a quadrate whorl section, an arched venter with a sub-acute keel-like elevation, and spiny tubercles on the ventrolateral shoulders as well as numerous regularly spaced, radial or slightly prorsiradiate ribs. Because the range of Marcouxia is limited to the Columbites parisianus Subzone of the lower Spathian (upper Olenekian, Lower Triassic) in the western USA, the age of Thaisaurus is likely constrained to the early Spathian, thus suggesting it is one of the oldest known ichthyopterygians.

Four coracoids belonging to the family Plotopteridae have been found from the Oligocene Ashiya Group, northern Kyushu, Japan. One coracoid is assigned to Copepteryx hexeris, and the other coracoids are assigned to new genera and species: Stenornis kanmonensis gen. et sp. nov., and Empeirodytes okazakii gen. et sp. nov., of the Plotopteridae. Stenornis and Empeirodytes share a synapomorphy: an elongate sulcus on the ventral surface of the facies articularis humeralis portion of the shaft, which is not observed in coracoids of other plotopterids. These new plotopterids reveal that the diversity of this group in the Oligocene Ashiya Group is higher than previously realized.

An early Asselian ammonoid fauna comprising nine species belonging to nine genera (Agathiceras, Neoglaphyrites, Somoholites, Shumardites, Vidrioceras, Almites, Eoasianites?, Boesites and Metapronorites) and one indeterminable Adrianitidae is described from the Uyamanoro Formation of the Taishaku Limestone at Miharanoro in the Akiyoshi Belt (late Permian accretionary belt), Southwest Japan. The fauna includes four new species: Shumardites umbilicatus, Vidrioceras ellipticum, Almites hayasakai and Boesites biconcavus. The age of the fauna is determined to be early Asselian based on the fusulinoidean biostratigraphy. In addition to the previously known late Asselian taxa, the number of Taishaku Asselian ammonoid genera is now ten genera. This is the only known Asselian ammonoid fauna from the mid-Panthalassa Ocean. The ammonoid faunal composition of this region, the Mid-Panthalassa Realm, is closely related to those of Paleotethyan (Pamirs and South China), Uralian and American (eastern Panthalassa) realms.