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''Odobenocetops'' () was a small toothed whale known from the Late Miocene of Peru and Chile.〔〔 〕 It had two tusks, and, in some fossils, one tusk was longer than the other. ==Phylogeny== ''Odobenocetops'' can be identified as a cetacean based several features unique to this order: # The presence of large air sinuses in the auditory region connected to large pterygoid sinuses. # The large supraorbital process of the frontal bone overhanging the orbital region. # Narial fossae opening dorsally (thought not at the apex of the skull like in other cetaceans.) # The absence of a true cribriform plate (a bony blade separating the nares). In ''Odobenocetops'', a group of foramina in this plate allows the passage of olfactory nerves connected to the small olfactory lobes in the brain. In other cetaceans, the olfactory nerves are similarly present but strongly reduced. # The elbow joint is immobile, as shown by a single partial forelimb. placed Odobenocetopssidae in a large clade together with Phocoenidae (porpoises), Monodontidae (narwhal and beluga), and Albireonidae (extinct porpoise-like). This clade originated in the Pacific Ocean in the Langhian (15-13 ma) and diversified from there during the Serravallian and Tortonian (13-7 ma). According to the morphological analysis of Murakami et al., ''Odobenocetops'' belongs to the middle Pliocene. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Odobenocetops」の詳細全文を読む スポンサード リンク
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