远古龙属

远古龙属; 化石时期：晚白垩世，72–68 Ma PreЄ Є O S D C P T J K Pg N ▼
	凯氏远古龙的复原图（英语：Life restoration）
科学分类
界：	动物界 Animalia
门：	脊索动物门 Chordata
纲：	爬行綱 Reptilia
目：	†蛇頸龍目 Plesiosauria
科：	†薄板龙科 Elasmosauridae
属：	†远古龙属 Tuarangisaurus; Wiffen（英语：Joan Wiffen） & Moisley, 1986
模式種
	†凯氏远古龙; Tuarangisaurus keyesi; Wiffen & Moisley, 1986

远古龙（学名：Tuarangisaurus，毛利語：tuarangi［古代的］ + 希臘語：σαῦρος，羅馬化：sauros［蜥蜴］）是薄板龙科已灭绝的一个属，化石发现于新西兰。模式种兼唯一已知物种是凯氏远古龙（Tuarangisaurus keyesi），由威芬（英语：Joan Wiffen）和莫伊斯利于1986年（英语：1986 in paleontology）命名。^[1]^[2]

发现

卡氏远古龙（现视为分类不明的极泳龙亚科）的骨骼重建

已知化石包括正模标本NZGS（英语：New Zealand Geological Survey） CD425，含有几乎完整的颅骨及下颌骨——及NZGS CD426，含前九节颈椎。一些幼龙颅后（英语：postocrania）遗骸亦归入远古龙，其中一件标本（NZGS CD427）含有至少30颗胃石。^[1]其收集于塔霍拉组（英语：Tahora Formation）曼加塔尼瓦砂岩段（Maungataniwha Sandstone Member），时间为晚白垩世坎帕阶晚期至马斯特里赫特阶早期。^[2]

第二个种澳洲远古龙（T. australis）于2005年命名，^[3]但于2007年移入新属伊罗曼加龙，成为嵴颌伊罗曼加龙（E. carinognathus）的首异名。^[4]第三个种卡氏远古龙（T.? cabazai）在原始描述中亦归入本属，^[1]但近期被重新归为分类不明的极泳龙亚科。^[5]

2017年，一件原属毛伊龙的完整标本（CM Zfr 115）被重新归入该属，^[6]2018年，奥特罗等人报告了一具幼龙标本，表明了这种蛇颈龙的个体发育。该标本具有很多与正模标本相同的特征，但上颌骨方向及牙齿数目存在差异。^[7]

描述

远古龙是种中型蛇颈龙，完整标本（CM Zfr 115）长度测为超过8米（26英尺）。^[8]颅骨保存部分长度测为37.0厘米（1英尺2.6英寸）左右，完整长度估计为37.5厘米（1英尺2.8英寸）。^[1]该属可根据一个独特的特征组合及两项此前未知的特征，与所有其它薄板龙科区分开来：外翼骨有一个朝向背侧的细长突起，下侧有一大型骨质突起。正模标本中存在一个镫骨，此前认为薄板龙科不具有这种骨骼。^[2]^[9]

分类

远古龙最初被归入薄板龙科，^[1]一项研究发现其为卡拉瓦亚龙的近亲。^[10]奥戈曼等人2016年的系统发育分析再次确认其属于薄板龙科，但否认其与卡拉瓦亚龙近缘。根据分析，该属在薄板龙科中的位置如下。^[2]

薄板龙科 Elasmosauridae

格罗诺龙 Gronausaurus

斯皮顿黏土的蛇颈龙

贝茜尼可斯白浪泳龙 Wapuskanectes betsynicollsae

哥伦比亚卡拉瓦亚龙 Callawayasaurus colombiensis

	斯氏神河龙 Styxosaurus snowii

	铃木双叶龙 Futabasaurus suzukii

	范氏阿尔伯塔泳龙 Albertonectes vanderveldei

	凯氏远古龙 Tuarangisaurus keyesi

	哈氏海霸龙 Thalassomedon haningtoni

	扁尾薄板龙 Elasmosaurus platyurus

庞泰克斯末泳龙 Terminonatator ponteixensis

亚历山大水怪龙 Hydrotherosaurus alexandrae

摩氏西南泳龙 Libonectes morgani

海洋卡瓦泳龙 Kawanectes lafquenianum

莫氏维加龙 Vegasaurus molyi

斯氏莫雷诺龙 Morenosaurus stocki

	卡提基猎蛸龙 Kaiwhekea katiki

	小齿极泳龙 Aristonectes parvidens

	基里奎纳极泳龙 Aristonectes quiriquinensis

参见

蛇颈龙列表
蛇颈龙类研究历史（英语：Timeline of plesiosaur research）

参考资料

^ ^1.0 ^1.1 ^1.2 ^1.3 ^1.4 Wiffen, J.; Moisley, W.L. Late Cretaceous reptiles (Families Elasmosauridae and Pliosauridae) from the Mangahouanga Stream, North Island, New Zealand. New Zealand Journal of Geology and Geophysics. 1986, 29 (2): 205–252. Bibcode:1986NZJGG..29..205W. doi:10.1080/00288306.1986.10427535.
^ ^2.0 ^2.1 ^2.2 ^2.3 O'Gorman, J.P.; Otero, R.A.; Hiller, N.; Simes, J.; Terezow, M. Redescription of Tuarangisaurus keyesi (Sauropterygia; Elasmosauridae), a key species from the uppermost Cretaceous of the Weddellian Province: Internal skull anatomy and phylogenetic position. Cretaceous Research. 2016, 71: 118–136. doi:10.1016/j.cretres.2016.11.014.
^ Sachs, S. Tuarangisaurus australis sp. nov. (Plesiosauria: Elasmosauridae) from the Lower Cretaceous of northeastern Queensland, with additional notes on the phylogeny of the Elasmosauridae (PDF). Memoirs of the Queensland Museum. 2005, 50 (2): 425–440. （原始内容 (PDF)存档于2011-09-28）.
^ Benjamin P. Kear. Taxonomic clarification of the Australian elasmosaurid genus Eromangasaurus, with reference to other austral elasmosaur taxa. Journal of Vertebrate Paleontology. 2007, 27 (1): 241–246. S2CID 86673814. doi:10.1671/0272-4634(2007)27[241:TCOTAE]2.0.CO;2.
^ O'Gorman, J.P.; Gasparini, Z.; Salgado, L. Reappraisal of Tuarangisaurus? cabazai (Elasmosauridae, Plesiosauria) from the Upper Maastrichtian of northern Patagonia, Argentina. Cretaceous Research. 2014, 47: 39–47. Bibcode:2014CrRes..47...39O. doi:10.1016/j.cretres.2013.10.003. hdl:11336/37287  .
^ Hiller, Norton; O'Gorman, José P.; Otero, Rodrigo A.; Mannering, Al A. A reappraisal of the Late Cretaceous Weddellian plesiosaur genus Mauisaurus Hector, 1874. New Zealand Journal of Geology and Geophysics. 2017, 60 (2): 112–128. Bibcode:2017NZJGG..60..112H. S2CID 132037930. doi:10.1080/00288306.2017.1281317.
^ Otero, R.A.; O'Gorman, J.P.; Moisley, W.L.; Terezow, M.; Mckee, J. A juvenile Tuarangisaurus keyesi Wiffen and Moisley, 1986 (Plesiosauria, Elasmosauridae) from the Upper Cretaceous of New Zealand, with Remarks on Its Skull Ontogeny. Cretaceous Research. 2018, 85: 214–231. Bibcode:2018CrRes..85..214O. doi:10.1016/j.cretres.2017.09.007. hdl:11336/99631  .
^ O'Gorman, J.P. A Small Body Sized Non-Aristonectine Elasmosaurid (Sauropterygia, Plesiosauria) from the Late Cretaceous of Patagonia with Comments on the Relationships of the Patagonian and Antarctic Elasmosaurids. Ameghiniana. 2016, 53 (3): 245–268. S2CID 133139689. doi:10.5710/AMGH.29.11.2015.2928.
^ Carpenter, K. Revision of North American elasmosaurs from the Cretaceous of the western interior. Paludicola. 1999, 2: 148–173.
^ Kubo, T.; Mitchell, M.T.; Henderson, D.M. Albertonectes vanderveldei, a new elasmosaur (Reptilia, Sauropterygia) from the Upper Cretaceous of Alberta. Journal of Vertebrate Paleontology. 2012, 32 (3): 557–572. Bibcode:2012JVPal..32..557K. S2CID 129500470. doi:10.1080/02724634.2012.658124.

[desc-1] 1.0 ^1.1 ^1.2 ^1.3 ^1.4 Wiffen, J.; Moisley, W.L. Late Cretaceous reptiles (Families Elasmosauridae and Pliosauridae) from the Mangahouanga Stream, North Island, New Zealand. New Zealand Journal of Geology and Geophysics. 1986, 29 (2): 205–252. Bibcode:1986NZJGG..29..205W. doi:10.1080/00288306.1986.10427535.

[redesc-2] 2.0 ^2.1 ^2.2 ^2.3 O'Gorman, J.P.; Otero, R.A.; Hiller, N.; Simes, J.; Terezow, M. Redescription of Tuarangisaurus keyesi (Sauropterygia; Elasmosauridae), a key species from the uppermost Cretaceous of the Weddellian Province: Internal skull anatomy and phylogenetic position. Cretaceous Research. 2016, 71: 118–136. doi:10.1016/j.cretres.2016.11.014.

[eromanga-3] Sachs, S. Tuarangisaurus australis sp. nov. (Plesiosauria: Elasmosauridae) from the Lower Cretaceous of northeastern Queensland, with additional notes on the phylogeny of the Elasmosauridae (PDF). Memoirs of the Queensland Museum. 2005, 50 (2): 425–440. （原始内容 (PDF)存档于2011-09-28）.

[Eromangasaurus07-4] Benjamin P. Kear. Taxonomic clarification of the Australian elasmosaurid genus Eromangasaurus, with reference to other austral elasmosaur taxa. Journal of Vertebrate Paleontology. 2007, 27 (1): 241–246. S2CID 86673814. doi:10.1671/0272-4634(2007)27[241:TCOTAE]2.0.CO;2.

[cabazai-5] O'Gorman, J.P.; Gasparini, Z.; Salgado, L. Reappraisal of Tuarangisaurus? cabazai (Elasmosauridae, Plesiosauria) from the Upper Maastrichtian of northern Patagonia, Argentina. Cretaceous Research. 2014, 47: 39–47. Bibcode:2014CrRes..47...39O. doi:10.1016/j.cretres.2013.10.003. hdl:11336/37287  .

[6] Hiller, Norton; O'Gorman, José P.; Otero, Rodrigo A.; Mannering, Al A. A reappraisal of the Late Cretaceous Weddellian plesiosaur genus Mauisaurus Hector, 1874. New Zealand Journal of Geology and Geophysics. 2017, 60 (2): 112–128. Bibcode:2017NZJGG..60..112H. S2CID 132037930. doi:10.1080/00288306.2017.1281317.

[7] Otero, R.A.; O'Gorman, J.P.; Moisley, W.L.; Terezow, M.; Mckee, J. A juvenile Tuarangisaurus keyesi Wiffen and Moisley, 1986 (Plesiosauria, Elasmosauridae) from the Upper Cretaceous of New Zealand, with Remarks on Its Skull Ontogeny. Cretaceous Research. 2018, 85: 214–231. Bibcode:2018CrRes..85..214O. doi:10.1016/j.cretres.2017.09.007. hdl:11336/99631  .

[8] O'Gorman, J.P. A Small Body Sized Non-Aristonectine Elasmosaurid (Sauropterygia, Plesiosauria) from the Late Cretaceous of Patagonia with Comments on the Relationships of the Patagonian and Antarctic Elasmosaurids. Ameghiniana. 2016, 53 (3): 245–268. S2CID 133139689. doi:10.5710/AMGH.29.11.2015.2928.

[carpenter-9] Carpenter, K. Revision of North American elasmosaurs from the Cretaceous of the western interior. Paludicola. 1999, 2: 148–173.

[callawaya-10] Kubo, T.; Mitchell, M.T.; Henderson, D.M. Albertonectes vanderveldei, a new elasmosaur (Reptilia, Sauropterygia) from the Upper Cretaceous of Alberta. Journal of Vertebrate Paleontology. 2012, 32 (3): 557–572. Bibcode:2012JVPal..32..557K. S2CID 129500470. doi:10.1080/02724634.2012.658124.

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