It is known that the mammoth fauna was distributed on the Japanese archipelago during the late Late Pleistocene. However, the number of mammalian fossils related to this fauna is small, and therefore only fragmental information of the fauna is known. To overcome this lack of information, we visited Harbin and Daqing Cities of Heilongjiang Province, China, in order to understand the mammoth fauna in Northeast China. Similar to Japan, temperate animal species, namely giant deer (Megaceros ordosianus), water buffalo (Bubalus wansjocki), wild boar (Sus scrofa), and tiger (Panthera tigris), are also found with the mammoth fauna in Heilongjiang, because this area was close to the southern distribution limit of the mammoth fauna. The mammoth fauna in Heilongjiang is therefore helpful in considering the Japanese mammoth fauna.

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 Aiming at detailed three-dimensional modeling of paleontological samples, we combined the synchrotron-based fine imaging and 3D printing techniques. Fine observation of microfossil was performed using synchrotron-based micro computed tomography (CT) system at the beamline 07 of Saga Light Source, and high-contrast observation of an insect embedded in amber was performed using phasecontrast X-ray imaging system at the same beamline. 3D models of microfossil and the insect created using commercial 3D printing machine with obtained fine data showed detailed surface and inner structures.

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 Samples for palynological analysis were taken from the upper part of the Tamagawa Formation (Late Cretaceous, Turonian) of the Kuji Group, at an outcrop rich in terrestrial vertebrate fossils located along the Osawada River, Kuji City, Iwate Prefecture. The palynoassemblage is composed of 81 morphospecies. It is dominated by spores of Filicophyta and Lycophyta, and pollen of Coniferales, while angiosperm pollen is very scarce in comparison with other localities of the formation. Fungi, algae and foraminifers were also obtained. The assemblage has a composition coherent with previously described micro- and macro-floras. It confirms a fluvial deposition and suggests a warm climate with humid conditions.

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 Elasmobranch fossils have been found from the upper part of the Late Cretaceous Tamagawa Formation (Turonian- Santonian/Coniasian) of the Kuji Group, Iwate Prefecture, Northeast Japan. Teeth belonging to Cretoxyrhinidae (Cretalamna), Mitsukurinidae (Scapanorhynchus), Odontaspididae, and Sclerorhynchidae were identified. All of these elasmobranch fossils have been assumed to be marine species. However, it is thought that their habitat reached to the estuary environment, because the estimation of the sedimentary environment of the stratigraphic horizon of the fossils based on the sedimentary facies analysis is like that. The present study shows implications for the paleoecology of possible non-marine, brackish or euryhaline elasmobranchs from the North Pacific area in the Late Cretaceous.

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