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''Dolichorhynchops'' is an extinct genus of polycotylid plesiosaur from the Late Cretaceous (early Turonian to late Campanian stage) of North America, containing three species, ''D. osborni'', ''D. herschelensis'' and ''D. tropicensis''.〔 ''Dolichorhynchops'' was an oceangoing prehistoric reptile. Its Greek generic name means "long-nosed face". ==''D. osborni''== The holotype specimen of ''Dolichorhynchops osborni'' was discovered in the upper Smoky Hill Chalk Logan County, Kansas, by George F. Sternberg, as a teenager, in around 1900. The remains were collected by him and his father, Charles H. Sternberg, and then sold to the University of Kansas (Lawrence, Kansas). KUVP 1300〔(【引用サイトリンク】title=Image: plio-lrg.jpg, (2175 × 600 px) )〕 was prepared and mounted by H.T. Martin under the supervision of Dr. Samuel Wendell Williston, who described and named it in 1902. A more detailed description and photographs were provided by ). The specimen has been on display in the KU Museum of Natural History since that time. In 1918, Charles H. Sternberg found a large mosasaur, ''Tylosaurus'', with the remains of a plesiosaur in its stomach.〔(【引用サイトリンク】title=Tylosaur food )〕 The mosasaur specimen is currently mounted in the United States National Museum (Smithsonian) and the plesiosaur remains are stored in the collections. Although these important specimens were briefly reported by , the information was lost to science until 2001. This specimen was rediscovered and described by . It is the basis for the story line in the 2007 National Geographic IMAX documentary ''Sea Monsters: A Prehistoric Adventure'', and a book by the same name . George Sternberg found a second, less complete specimen of ''D.osborni'' in 1926. In his effort to sell the specimen to a museum, Sternberg took detailed photographs of the skull.〔(【引用サイトリンク】title=Image: mcz5086a.jpg, (1336 × 742 px) )〕 The specimen was eventually mounted in plaster and was acquired by the Harvard Museum of Comparative Zoology. MCZ 1064〔(【引用サイトリンク】title=Image: 1064-4.jpg, (1000 × 297 px) )〕 was on display there until some time in the 1950s. This specimen was never completely described although the skull was figured by . (See also ) The specimen of ''D. osborni'' on exhibit at the Sternberg, FHSM VP-404〔(【引用サイトリンク】title=Image: vp-404.jpg, (1160 × 404 px) )〕 was found by Marion Bonner near Russell Springs in Logan County in the early 1950s. It is, perhaps, the most complete specimen of this species known. It was about 3 metres in length. The skull〔(【引用サイトリンク】title=VP-404 skull )〕 was crushed flat but is in very good condition. This specimen was initially reported by , and then was the subject of a Masters thesis by . Note that it was described by Bonner as ''"Trinacromerum osborni"'' which was the accepted genus name at the time. Two very large specimens of a polycotylid plesiosaur (KUVP 40001 and 40002〔(【引用サイトリンク】title=Image: KU40001-4.jpg, (589 × 500 px) )〕) were collected from the Pierre Shale of Wyoming and later reported on by Adams in her 1977 Masters thesis. Later (1997), she officially described (1997) as a new species of ''Trinacromerum'' (T''. bonneri''). Unknown to her at the time, Carpenter (1996) had revised the Polycotylidae and separated ''Dolichorhynchops'' from ''Trinacromerum''. Thus the species would revert to ''Dolichorhynchops bonneri'', but there is some question as to whether or not the specimens represent a separate species or just larger individuals of ''D. osborni''. The question has yet to be resolved. Until recently, all known specimens of ''D. osborni'' in Kansas had been collected from the upper layers of the Smoky Hill Chalk (Campanian age). reported the first remains from the lower chalk (Late Coniacian-Santonian in age). In 2005, the remains of the earliest known ''D. osborni'' were discovered in the Fort Hays Limestone, Niobrara Formation in Jewell County, Kansas. This is the first record of a polycotylid plesiosaur in this formation. 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「Dolichorhynchops」の詳細全文を読む スポンサード リンク
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