Taxonomic studies on fossil anurans and lizards from the Early Cretaceous Sasayama Group, Hyogo, Japan.

• Project/Area Number: 26870925
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Biodiversity/Systematics; Stratigraphy/Paleontology
• Research Institution: The Museum of Nature and Human Activities, Hyogo
• Principal Investigator: Ikeda Tadahiro 兵庫県立人と自然の博物館, その他部局等, 研究員 (50508455)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2014: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 下部白亜系 / 篠山層群 / トカゲ / カエル / 新属・新種 / カエル類化石 / トカゲ類化石 / カエル化石 / トカゲ化石 / 記載・分類

Outline of Final Research Achievements

Numerous anuran and lizard fossils have been found from the Lower Cretaceous Sasayama Group together with dinosaurs. In present study, we investigated the taxonomic assignments for two nearly complete specimens of fossil anurans and twelve cranial specimens of fossil lizards, on the basis of comparative morphological studies between these and Mesozoic or archaic taxa. As the results, two specimens of anurans were described as novel, two distinct taxa, and the lizard specimens were identified as two types of genus Pachygenys including a new taxon, and six types of sincomorphans. Although the discovery of genus Pachygenys from the Sasayama Group represents the faunal correlation of lizards between Japan and eastern Eurasia, the two anurans and other lizard fossils from the Sasayama Group did not show any evidence of their particularly close affinity to anurans and lizards from the Lower Cretaceous of the eastern Eurasia.

Research Products

• [Journal Article] Dinosaur eggshell assemblage from Japan reveals unknown diversity of small theropods (2016)
  • Author(s): Kohei T., Zelenitsky, D. K., Saegusa, H., Ikeda, T., DeBuhr, C. L., Therrien, F.
  • Journal Title: Cretaceous Research Volume: 57 Pages: 350-363
  • DOI: 10.1016/j.cretres.2015.06.002
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] New fossil anurans from the Lower Cretaceous Sasayama Group of Hyogo Prefecture, Western Honshu, Japan (2016)
  • Author(s): Ikeda T., Ota, H., Matsui, M
  • Journal Title: Cretaceous Research Volume: 61 Pages: 108-123
  • DOI: 10.1016/j.cretres.2015.12.024
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] 兵庫県の下部白亜系篠山層群から発見されたカエル類化石について (2015)
  • Author(s): 池田忠広・太田英利・松井正文・三枝春生・半田久美子
  • Organizer: 日本爬虫両棲類学会54回年会
  • Place of Presentation: 東邦大学、千葉県
  • Year and Date: 2015-12-05
• [Presentation] Fossil Anurans and Lizards Found from the Lower Cretaceous Sasayama Group of Hyogo Prefecture, Western Honshu, Japan. (2015)
  • Author(s): Ikeda, T., Ota, H., Saegusa, H., and Handa, K.
  • Organizer: The 2nd International symposium on Asian Dinosaurs in Thailand
  • Place of Presentation: Bangkok, Thailand
  • Year and Date: 2015-11-19
  • Int'l Joint Research
• [Presentation] The Vertebrate fossil assemblages from the Lower Cretaceous Sasayama Group, Hyogo, Prefecture, Western Honshu, Japan. (2014)
  • Author(s): Ikeda, T., Saegusa, H. and Handa, K.
  • Organizer: Mid-Mesozoic Conference.
  • Place of Presentation: Fruta, Colorado, USA
  • Year and Date: 2014-04-29 – 2015-05-05
• [Remarks] 人と自然の博物館 研究員紹介
  • URL: http://www.hitohaku.jp/researchers/ikeda.html
• [Remarks] 人と自然の博物館 ひとはくの研究 篠山市より発掘されたトカゲ類の記載論文の出版について
  • URL: http://www.hitohaku.jp/research/h-research/kaseki-20150204news.html
• [Remarks] 人と自然の博物館 ひとはくの研究 篠山層群より産出したカエル類化石の記載論文の出版について
  • URL: http://www.hitohaku.jp/research/h-research/kaseki-20160203.html