Reinterpretation of some cranial structures of Desmostylus hesperus (Mammalia: Desmostylia) : a new specimen from the Middle Miocene Tachikaraushinai Formation, Hokkaido, Japan
スポンサーリンク
概要
- 論文の詳細を見る
A new skull of Desmostylus Hesperus Marsh, 1888 is described from the late Middle Miocene Tachikaraushinai Formation, Utanobori, Hokkaido, northern Japan. The specimen, GSJ-F7745, is a nearly complete skull and mandible, but the posterior halves of their left sides are missing. It was a juvenile individual, having part of the worn fourth deciduous molar (dp^4) in the right upper jaw. Another specimen (GSJ-F7743) was uncovered in the same formation near the same area where GSJ-F7745 was collected. Both fossils represent nearly the same ontogenetic stage and were of the same gender. There are two different opinions regarding the position of the external acoustic meatus of Desmostylus. The cranial cavity of specimen GSJ-7745 is observable and reveals that the meatus should be identified as being the foramen on the lateral surface of the posterior portion of the zygomatic arch.
- 日本古生物学会の論文
- 2004-04-30
著者
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Uno Hikaru
Division Of Earth And Planetary Sciences Graduate School Of Science Hokkaido University
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KIMURA MASAICHI
Hokkaido University of Education