Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Poster

B (Biogeosciences) » B-PT Paleontology

[B-PT06] Biotic History

Sun. May 20, 2018 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Isao Motoyama(Department of Earth and Environmental Sciences, Yamagata University), Takao Ubukata(Division of Geology & Mineralogy, Department of Earth & Planetary Sciences, Kyoto University), Kazuyoshi Moriya(早稲田大学 教育・総合科学学術院 地球科学専修)

[BPT06-P03] Can we identify Desmostylia based on only humeral morphology?

*Kumiko Matsui1 (1.National Science Museum)

Keywords:Taxonomy, Vertebrate Paleontology, Desmostylia

Desmostylia is one clade of extinct marine mammals. They belong Tethyteria (Afrotheria) or Perissodactyla (Laurasiatheria) and existed during the period between the early Oligocene and late Miocene. All occurrences of their fossils are limited to marine strata along the coasts of the North Pacific Ocean. Desmostylian fossils in many shapes and forms, including whole or partial skeletons, skulls, teeth, and fragmentary bones have been discovered from both Pacific coasts, but detailed taxonomic identification based on fragmentary or isolated postcranial materials has been difficult owing to our limited knowledge of the postcranial diagnostic features of desmostylian taxa.

For this reason, I established desmostylian diagnostic characters found in the humerus to identify desmostylian genus. I could found 6 diagnostic characters for desmostylia, 5 diagnostic characters for Behemotops, 7 diagnostic characters for Archaeoparadoxia, 7 diagnostic characters for Paleoparadoxia, 4 diagnostic characters for Neoparadoxia, 6 diagnostic characters for Ashoroa, and 6 diagnostic characters for Desmostylus. All these characters found in this study can be used to identify isolated desmostylian humeri to genus level. Therefore, these results will contribute a better understanding of the stratigraphic and geographic distribution of each desmostylian genus.