著者

高橋 啓一

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.35, pp.1-253, 2022 (Released:2022-12-22)

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I. History of studies 1. Dawn of research 2. Development (2.1 Progress of phylogenetic studies,2.2 Development of stratigraphic studies, 2.3 Studies of morphological reconstructions) 3. Period of new studies (3.1 Phylogenetic problems, 3.2 Mutations, 3.3 Chronology and distribution) II. Localities 1. On the previous and updated locality list 2. Updated locality list (2.1 Hokkaido and Tohoku regions, 2.2 Kanto region, 2.3 Chubu region, 2.4 Kinki, Chugoku, Shikoku and Kyusyu regions) III. Stratigraphic distribution 1. Study history 2. Age of first appearance 3. Formation of the Kanto Plain and sediments including P. naumanni (3.1 Transition of the plain and sedimentary environment, 3.2 Sedimentary facies and mode of occurrence of P. naumanni on the Boso Peninsula, 3.3 Occurrence in Tokyo) 4. Age of extinction and causes (4.1 Age of extinction, 4.2 Causes of extinction) IV. Morphology 1. Morphology of each part (1.1 Cranium, 1.1.1 Terminology, 1.1.2 Characteristics, 1.1.3 Sex dimorphism 1.2 Mandible, 1.3 Tusks, 1.4 Molars, 1.4.1 Characteristics of the genus, 1.4.2 species characteristics of the species, 1.4.3 Characteristics of upper and lower molars,1.4.4 Differences of tooth type, 1.4.5 Variation of molars n regional populations,1.4.6 Morphological changes due to occlusal wear and age assessment, 1.4.7 Sex dimorphism in molars,1.4.8 Pathological morphology, 1.4.9 Histological and biochemical studies, 1.5Hyoid bones, 1.5.1 Morphology of the stylohyoid, 1.5.2 Features and variation of the stylohyoid, 1.6 Axial skeleton, 1.6.1 Spinal column and vertebrae, 1.6.2 Ribs, 1.7 Limbs, 1.7.1Scapula, 1.7.2 Humerus, 1.7.3 Ulna, 1.7.4 Radius, 1.7.5 Forefoot bones (carpus metacarpus, phalanges), 1.7.6 Innominate bone, 1.7.7 Femur,1.7.8 Patella, 1.7.9 Tibia, 1.7.10 Fibula, 1.7.11 Hind foot bones (tarsus, metatarsus, phalanges) 2. Reconstructions (2.1 Skeletal reconstructions, 2.2 Biological reconstructions) 3. Fossil Footprints V. Phylogeny and classification 1. Taxonomic position of the genus Palaeoloxodon 2. Dispersal of the genus Palaeoloxodon 3. Taxonomic position of P. naumanni VI. Habitat and fauna 1. Habitat 2. Vertical distribution 3. Fauna (3.1 Pleistocene terrestrial mammalian stratigraphy, 3.2 Mammals coexisting with P. naumanni, 3.3 Two faunas of the Late Pleistocene)

著者

柏尾 珠紀

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.36, pp.5-89, 2023 (Released:2023-04-03)

著者

澁谷 一成

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.25, pp.85-148, 2010 (Released:2022-12-24)

著者

中嶋 雅子

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.35, pp.254-309, 2022 (Released:2022-12-22)

著者

青木 良輔

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.31, pp.42-47, 2018 (Released:2021-12-27)

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The crocodilian caudal vertebra is obtained from the Tsubusagawa Formation. Its size is same and its gross shape is resemblance to the 20th caudal vertebra of Crocodylus porosus, NTM R16036, total length for 513 cm. However, in comparison with NTM R16036, the direction of neural spine is more dorsocaudal, and the M. longissimus caudae and M. semispinalis caudae might be more developed in the Tsubusagawa specimen. With respects to the hitherto regarding crocodilian fauna, the Tsubusagawa specimen is identified to the crocodyline crocodylid, Toyotamaphimeia machikanensis. The caudal vertebrae are preserved only three, 1st to 3rd , in the type specimen of T. machikanense, and thus direct comparison with the Tsubusagawa specimen is impossible. According to Chinese classic dictionary by Lu (1174, the 12th Century), the tail of crocodile which may be identified as T. machikanensis is prehensile as if elephant trunk. The posterior condyle of this vertebra is well developed, and thus there is some possibility to support the evidence of prehensile tail. At the early Miocene, T. machikanensis might be derived from crocodyline crocodylid Maomingosuchus petrolicus. T. machikanensis is differ from Maomingosuchus petrolicus in having the largest 7th maxillary teeth and much larger body. The large canini-form development of 7th maxillary teeth is an adaptation for the relatively larger prey. As a larger prey, the presence of oxygasterine cyprinid Hypophthalmichthys (Silver Asian Carp), total length for 1 metre or more, is seemed to be involved with the secondary caniniform development of 7th maxillary teeth and gigantism of Toyotamaphimeia. The oldest fossil record of Toyotamaphimeia is the early Miocene and that of Hypophthalmichthys is too. Hypophthalmichthys is famous for its frequently jumping when disturbed. Although this jumping is hitherto claimed as enigmatic, it could be interpreted as anti-predatory behavior against Toyotamaphimeia.

著者

白勢 洋平

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.33, pp.5-17, 2021 (Released:2021-11-14)

参考文献数

33

著者

加藤 敬史 北林 栄一

出版者

滋賀県立琵琶湖博物館

雑誌

琵琶湖博物館研究調査報告 (ISSN:2436665X)

巻号頁・発行日

vol.31, pp.48-55, 2018 (Released:2021-12-27)

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Fossil rodents, represented by nine isolated teeth, were obtained by wet sieving sediments from the Upper Pliocene Tsubusagawa Formation in Ajimu, Oita Prefecture. The rodent remains include Micromys sp., Arvicolinae gen. et sp. indet., and unidentified incisors. This is the first report of the Pliocene rodent fauna in Japan. Micromys sp. fossils differ from modern species in occlusal outline, number of roots, crown size, position of t4 and t6, size of t9, and presence or absence of t7 in the upper M1. Arvicorinae gen. et sp. indet. have such features as a hypsodont, very high sinuous line, thick cementum, and relatively wide crown in comparison to other arvicolids. Historically, Micromys and Arvicolinae have had a Palearctic distribution. This is consistent with previous plant fossil research that indicates a temperate-zone climate in the lower to middle part of the Tsubusagawa Formation. However, it is not consistent with the fossil tortoise and large mammals included in the Ajimu Fauna, which represent a subtropical or tropical This contradiction may suggest that the fossil assemblage was formed in an environment under the transition from tropical to temperate zone in the gradually cooling climate of the Late Pliocene.