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''Mammalodon'' is an extinct genus of archaic baleen whales, although it lacked baleen and retained teeth. It was discovered in 1932 in the Jan Juc Formation on the small Bird Rock island south of the Point Lillias peninsula in Torquay, Victoria in Australia (, paleocoordinates ).〔. Retrieved October 2013.〕 It is one of two genera in the family Mammalodontidae. ==Description== ''Mammalodon'', with a length of , was smaller and more basal than modern baleen whales. ''Mammalodon'' is a mix of archaeocete plesiomorphies (retained primitive traits) and mysticete synapomorphies (traits shared with more derived taxa), such as a short rostrum, reduced premaxillae, and orbits directed anterodorsally — defining features of mysticete. It had a short face and a delicate premaxilla with only one or two incisors, and the lateral rim of the internal auditory meatus was lengthened towards the brain case which formed a longitudinal ridge. 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「Mammalodon」の詳細全文を読む スポンサード リンク
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