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''Andrewsiphius'' is an extinct remingtonocetid early whale known from the Eocene (Ypresian-Lutetian, ) of Gujarat and Kutch, India and Balochistan, Pakistan.〔. Retrieved July 2013.〕〔. Retrieved July 2013.〕 ''Andrewsiphius'' is similar to but smaller than ''Kutchicetus'' (another remingtonocetid); synonymized them, and proposed a new subfamily, Andrewsiphiinae, for the two species. Later authors,〔E.g., 〕 however, still accept both as separate genera. ''Andrewsiphius'' and ''Kutchicetus''share several characteristics not present in other remingtonocetis: an elongated snout that is higher than it is wide; Foramina (small holes) on the tip of the snout suggesting the presence of whiskers; eyes located dorsally near the cranial midline, resulting in an appearance of a mammalian crocodile; and a very large sagittal crest overhanging the back of the skull. Other characteristics make them distinct: the second and third upper and lower premolars are double-rooted in ''Andrewsiphius'' but single-rooted in ''Kutchicetus''; the large diastemata in the former are absent the latter; and the tail vertebrae are more robust in ''Andrewsiphius''. ''Andrewsiphius'' is, compared to the remgintonocetids ''Remingtonocetus'' and ''Dalanistes'', smaller, has a narrower rostrum, and smaller premolars separated by longer diastemata. The first specimen was collected by who described it as mandibular fragments of ''Protocetus sloani''. described two new species, ''Andrewsiphius kutchensis'' and ''A. minor'' based on their previous material and new mandibular fragments. Later researchers interpreted the same mandibular specimens as belonging to ''Remintonocetus''. reinterpreted these specimens as fragments from maxillae, and determined that the described "confluence of the mandibular canals anteriorly" was in fact the narial passages. Gingerich et al. also determined that the variations in size among proposed species were within the normal variation for a single species and therefore attributed a number of referred specimens as belonging to ''Andrewsiphius sloani''.〔 Gingerich et al. also noted that the type specimen of ''Kutchicetus minimus'' came from the same locality as ''A. sloani'' and that its distinctive small size was within the variation that could be expected for ''A. sloani'', and Gingerich et al. therefore included ''K. minimus'' into ''A. sloani''.〔 Later authors, however, disagreed on this assignment and ''Kutchicetus'' is still accepted as a separate genus.〔. Retrieved July 2013.〕 named the type species for Dr Robert E. Sloan, Department of Geology, University of Minnesota. ==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「Andrewsiphius」の詳細全文を読む スポンサード リンク
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