Three species of orthoconic cephalopods, Mooreoceras sp. and Atahococeras timorense gen. and sp. nov. of the Pseudorthoceratidae, and an indeterminate genus and species of the Bactritidae are described from the Lower Permian Atahoc Formation in the Cribas area, East Timor. Apparent changes in the surface ornamentation of Atahococeras are considered to be genus-level criteria that separate it from the most closely related genus, Bitaunioceras. This assemblage signifies a non-ammonoid cephalopod fauna in the northern margin of Gondwana near the Sakmarian/Artinskian boundary.

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Ancistrolepis (Ancistrolepis) iwakiensis sp. nov. from the lower Oligocene of the Joban coal field, northern Japan closely resembles both Ancistrolepis (A.) matchgarensis (Makiyama) from the upper Eocene to Oligocene of Sakhalin and Ancistrolepis (A.) rategiensis Titova from the upper Eocene of northwestern Kamchatka. A. (s.s.) iwakiensis sp. nov. documents an early evolutional history of Ancistrolepis (s.s.) that appeared in the northwestern Pacific during late Eocene time.

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A positive carbon isotopic excursion across the Cenomanian/Turonian boundary in the Kotanbetsu area, Hokkaido, Japan provides accurate positioning of the boundary. A microscopic study based on organic petrology reveals that the organic matter included in mudstones of the Kotanbetsu River section is exclusively terrestrial. The results of stratigraphic time-series analysis of stable carbon isotopes from these mudstone samples can be translated as representing an average of a terrestrial plant community signal. The isotopic fluctuation through this time interval records information on the global ocean-atmosphere system. Two internationally recognized events characterize the uppermost Cenomanian through middle Turonian. On the basis of this study the Cenomanian/Turonian boundary can be recognized within a stratigraphic range of ∼ 14 meters. This horizon of the boundary is concordant with that from biostratigraphy (ammonoids, inoceramids and planktonic foraminifers). Above the middle Turonian strata, the isotopic pattern supports the biochronology of planktonic foraminifers rather than that of inoceramids.

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Species of the tropical Indo-Pacific gastropod Pisulina (superorder Neritopsina), previously known only from empty shells and regarded as a genus of Smaragdiinae (Neritidae), are revised on conchological criteria. Pisulina dwells in gloomy to totally dark, tropical and subtropical, shallow-water submarine caves, where their empty shells are ubiquitous. Study of the previously described modern and fossil species and examination of newly collected material from more than 50 submarine caves on Pacific islands show that there are six species in the genus : P. adamsiana Nevill and Nevill, 1869 (Holocene), P. subpacifica Ladd, 1966 (late Miocene), P. biplicata Thiele, 1925 (Recent), P. maxima new species (Recent), P. tenuis new species (Recent), and Pisulina sp. (Pleistocene). An analysis of previously unstudied shell characters (shell form, shell microstructure, protoconch morphology, and opercular features) of Pisulina and other modern, representative genera of Neritopsina places the genus close to the freshwater and brackish-water genus Neritilia, based on three unique characters (inclined protoconch, spiral ridges on the protoconch surface, and perpendicularly arranged prisms in the outer shell layer), and both genera are herein included in the family Neritiliidae. This study shows that the protoconch and shell microstructure analysis is important for re-evaluating fossil species previously placed in Neritidae.

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The freshwater sponge Oncosclera kaniensis sp. nov. of the demospongian family Potamolepidae is described from the Early Miocene Nakamura Formation (Mizunami Group) in Gifu Prefecture, central Japan. This is the first fossil record of the Potamolepidae in the world and also is the first documentation of fossil sponges from the Nakamura Formation. Paleoecology of Oncosclera kaniensis sp. nov. is briefly discussed.

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Four new species of decapod crustaceans are described from the Upper Cretaceous Upper Yezo Group in Hokkaido, Japan. The monotypic genus Paki (Thalassinidea, Micheleidae) is erected with P. rurkonsimpu sp. nov. Hoploparia kamuy sp. nov. (Astacidea, Nephropidae) represents the first record of the genus Hoploparia from the Turonian-Santonian of Japan. Luisogalathea gen. nov. (Anomala, Galatheidae), erected with the type species L. tomitai sp. nov., contains two North American Cretaceous species, Galathea cretacea Stenzel and Eomunidopsis cobbani Bishop. Eomunidopsis kojimai sp. nov. (Anomala, Galatheidae) represents the first record of the genus from the North Pacific realm.

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A moderately well-preserved Llandoverian (early Early Silurian) radiolarian fauna has been discovered from the Ise area of the Hida "Gaien" Belt, in Izumi Village, Fukui Prefecture, central Japan. This is the oldest known radiolarian fauna in Japan, and was recovered from calcareous nodules in the siliceous shale portion of a sedimentary sequence consisting of siliceous shale, alternating tuffaceous sandstone and shale, and tuffaceous sandstone. The fauna contains Haplotaeniatum tegimentum, Syntagentactinia afflicta, S. excelsa, Oriundogutta sp., Inanihella sp., Auliela sp., Palaeoephippium? sp., and Orbiculopylorum sp. This fauna is characterized by an abundance of species in the genera Haplotaeniatum, Syntagentactinia and Oriundogutta, and is comparable with the early to middle Llandoverian Haplotaeniatum tegimentum Assemblage and its equivalents in the southern Urals, Germany, and Nevada. Seventeen species of radiolarians belonging to 12 genera were systematically investigated.

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