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''Babiacetus'' is an extinct genus of early cetacean that lived during the late Lutetian middle Eocene of India ().〔. Retrieved March 2013.〕〔. Retrieved April 2013.〕 It was named after its type locality, the Harudi Formation〔. Retrieved April 2013.〕 in the Babia Hills (: paleocoordinates ), Kutch District, Gujarat, India.〔 ''Babiacetus'' was named by in an abstract based on the type specimen (GSI 19647, left and right dentaries with cheek teeth). Gingerich and colleagues found a skull (GSP-UM 3005, much of a skull and lower jaws)〔 while collecting a skeleton of a new species of Protosiren (''Protosiren sattaensis'') in the Drazinda Formation (, paleocoordinates )〔. Retrieved April 2013.〕 in the Sulaiman Range of Punjab, Pakistan. described both the original find and their new specimen. described ''B. mishrai'' from the specimen (RUSB 2512, a partial skull)〔 collected in the Harudi Formation.〔〔. Retrieved March 2013.〕 ''Babiacetus'' is one of the larger protocetids. Its hydrodynamic skull and pointed, anteroposteriorly (front-back) oriented incisors are typical of archaeocetes. A densely ossified auditory bulla and large mandibular canal indicate it was adapted for hearing in water. ''Babiacetus'' differs from pakicetids and ambulocetids (more primitive families) by the large mandibular foramen and a medially concave ascending ramus; distinct from remingtonocetids and basilosauroids (more derived families) by the single-cusped trigonid and talonid on the lower molars.〔 Its long synostotic (fused) mandibular symphysis, which reaches as far back as P2, distinguishes it from ''Pappocetus'' and ''Georgiacetus'' (other protocetids). Its auditory bulla is more narrow than ''Rodhocetus'' The anterior premolars are large.〔 Its large size and robust teeth suggest that it fed on larger fishes or aquatic vertebrates, or both. Only cranial remains have been found, so nothing is known of ''Babicetus'' The mandible is longer in ''B. indicus'' than in ''B. mishrai'', and P1 is single-rooted in the former but double-rooted in the latter. The diastemata between P1 and P4 in ''B. indicus'' is absent in ''B. mishrai''. ''B. indicus'' has larger cheek teeth and a larger M3.〔 ==Notes== 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「Babiacetus」の詳細全文を読む スポンサード リンク
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