A new desmostylian mammal from Unalaska (USA) and the robust Sanjussen jaw from Hokkaido (Japan), with comments on feeding in derived desmostylids

作者:Chiba Kentaro; Fiorillo Anthony R; Jacobs Louis L*; Kimura Yuri; Kobayashi Yoshitsugu; Kohno Naoki; Nishida Yosuke; Polcyn Michael J; Tanaka Kohei
来源:Historical Biology, 2016, 28(1-2): 289-303.
DOI:10.1080/08912963.2015.1046718

摘要

Derived members of the enigmatic mammalian order Desmostylia have molars comprising appressed columns whose morphology does not render their function in feeding simple to discern. Here we describe a new genus and species, Ounalashkastylus tomidai, more derived than Cornwallius but less derived than Desmostylus and Vanderhoofius, which develop a hypertrophied medial eminence on the dentary ontogenetically. Tooth morphology, vaulted palate and the medial eminence, which can rise to the level of the occlusal surface of M-2, suggest that derived desmostylids clenched their teeth strongly while employing suction during feeding, most likely on marine and coastal plants.

  • 出版日期2016-2-17