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Ichthyosaurs from the Upper Triassic (Carnian–Norian) of the New Siberian Islands, Russian Arctic, and their implications for the evolution of the ichthyosaurian basicranium and vertebral column

Published online by Cambridge University Press:  13 December 2021

Nikolay G. ZVERKOV Open the ORCID record for Nikolay G. ZVERKOV [Opens in a new window] ,
Dmitry V. GRIGORIEV ,
Andrzej S. WOLNIEWICZ ,
Alexey G. KONSTANTINOV  and
Evgeny S. SOBOLEV
Nikolay G. ZVERKOV*
Affiliation:
Borissiak Paleontological Institute of the Russian Academy of Sciences, 123 Profsoyuznaya Street, Moscow 117997, Russia. Geological Institute of the Russian Academy of Sciences, 7 Pyzhevsky Lane, Moscow 119017, Russia.
Dmitry V. GRIGORIEV
Affiliation:
Faculty of Biology, St Petersburg State University, 7/9 Universitetskaya Embankment, St Petersburg 199034, Russia. Zoological Institute of the Russian Academy of Sciences, Universitetskaya Embankment 1, St Petersburg 199034, Russia.
Andrzej S. WOLNIEWICZ
Affiliation:
School of Resources and Environmental Engineering, Hefei University of Technology, 193 Tunxi Rd, Hefei 230009, Anhui, China. Institute of Paleobiology, Polish Academy of Sciences, 51/55 Twarda, Warsaw 00-818, Poland.
Alexey G. KONSTANTINOV
Affiliation:
Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, 3 Academician Koptug Avenue, Novosibirsk 630090, Russia.
Evgeny S. SOBOLEV
Affiliation:
Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, 3 Academician Koptug Avenue, Novosibirsk 630090, Russia.
*
*Corresponding author. Email: zverkovnik@mail.ru
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Abstract

The first ichthyosaurian specimens discovered from the Upper Triassic of the Russian Arctic (Kotelny Island, New Siberian Islands) are described herein. They include the remains of large- to small-bodied ichthyosaurians originating from six stratigraphic levels spanning the lower Carnian to middle Norian. The material is mostly represented by isolated vertebrae and ribs, which are not possible to accurately diagnose, but also includes specimens comprising associated vertebrae and a fragmentary skeleton that preserves cranial remains (parabasisphenoid, fragmentary quadrate, partial mandible and hyoids). Based on vertebral and rib morphology, we identify the specimens as representatives of the following taxonomic groups: large-bodied shastasaurids, medium-sized indeterminate ichthyosaurians with a single rib facet in the presacral centra, and small euichthyosaurians with double rib facets present throughout the presacral vertebrae that likely represent toretocnemids and/or basal parvipelvians. In addition, the cranial and mandibular remains preserved in one of the specimens, ZIN PH 5/250, were studied using micro-computed tomography. Its mandible is highly similar to that of toretocnemids, whereas the parabasisphenoid demonstrates a peculiar combination of both plesiomorphic and derived character states, providing the first detailed data on this cranial element in a Late Triassic ichthyosaurian. Furthermore, the specimen also demonstrates a distinctive condition of rib articulation in the anteriormost presacral (cervical) vertebrae, which together with other features allows for the erection of a new taxon – Auroroborealia incognita gen. et sp. nov. Although the phylogenetic position of this taxon is uncertain due to its fragmentary nature, its anatomy, indicating toretocnemid or parvipelvian affinities, further supports the previously hypothesised sister-group relationships between these two clades. The morphology of the parabasisphenoid and vertebral column of the new taxon is discussed in broader contexts of the patterns of evolution of these skeletal regions in ichthyosaurs.

Keywords

EuichthyosauriaIchthyosauriaLate TriassicNorianparabasisphenoidParvipelviaToretocnemidae
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Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 113 , Issue 1 , March 2022 , pp. 51 - 74
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Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of The Royal Society of Edinburgh

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References

8. References

Abramoff, M. D., Magelhaes, P. J. & Ram, S. J. 2004. Image processing with ImageJ. Biophotonics International 11, 36e42.Google Scholar
Adams, T. L. 2009. Deposition and taphonomy of the hound island late Triassic vertebrate fauna: fossil preservation within subaqueous gravity flows. Palaios 24, 603–15.CrossRefGoogle Scholar
Appleby, R. M. 1961. On the cranial morphology of ichthyosaurs. Proceedings of the Zoological Society of London 137, 333–70.CrossRefGoogle Scholar
Arkhangelsky, M. S., Zverkov, N. G., Zakharov, Yu. D. & Borisov, I. V. 2016. On the first reliable find of the genus Tholodus (Reptilia: Ichthyopterygia) in the Asian peripheral area of the Panthalassic Ocean. Paleontological Journal 50, 78–86.CrossRefGoogle Scholar
Benson, R. B. J. & Butler, R. J. 2011. Uncovering the diversification history of marine tetrapods: ecology influences the effect of geological sampling biases. Geological Society, London, Special Publications 358, 191–208.CrossRefGoogle Scholar
Bindellini, G., Wolniewicz, A. S., Miedema, F., Scheyer, T. M. & Dal Sasso, C. 2021. Cranial anatomy of Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 (Reptilia: Ichthyosauria) from the Middle Triassic Besano formation of Monte San Giorgio, Italy/Switzerland: taxonomic and palaeobiological implications. PeerJ 9, e11179.CrossRefGoogle Scholar
Bragin, N. Y. 2011. Triassic radiolarians of Kotel'nyi Island (New Siberian Islands, Arctic). Paleontological Journal 45, 711–78.CrossRefGoogle Scholar
Bragin, N. Y., Konstantinov, A.G. & Sobolev, E. S. 2012. Upper Triassic stratigraphy and paleobiogeography of Kotel'nyi Island (New Siberian Islands). Stratigraphy and Geological Correlation 20, 541–66.CrossRefGoogle Scholar
Brinkmann, W. 1998. Die ichthyosaurier (Reptilia) aus der Grenzbitumenzone (Mitteltrias) des Monte San Giorgio (Tessin, Schweiz) – neue ergebnisse. Vierteljahrsschrift der Naturforschenden Gesellschaft in Ziirich 143, 165–77.Google Scholar
Brinkmann, W. 2004. Mixosaurier (Reptilia, Ichthyosaurier) mit quetschzähnen aus der grenzbitumenzone (Mitteltrias) des Monte San Giorgio (Schweiz, Kanton Tessin). Schweizerische Paläontologische Abhandlungen 124, 1–86.Google Scholar
Callaway, J. & Massare, J. 1989. Shastasaurus altispinus (Ichthyosauria, Shastasauridae) from the Upper Triassic of the El Antimonio District, northwestern Sonora, Mexico. Journal of Paleontology 63, 930–39.CrossRefGoogle Scholar
Camp, C. L. 1980. Large ichthyosaurs from the Upper Triassic of Nevada. Palaeontographica 170, 139–200.Google Scholar
Dagys, A. S., Arkhipov, Y. V. & Bychkov, Y. M. 1979. Stratigraphy of the Triassic system of northeastern Asia. Moscow: Nauka. [In Russian.]Google Scholar
de Blainville, H. M. 1835. Description de quelques espèces de reptiles de la californie: précédée de l'analyse d'un système général d'erpétologie et d'amphibiologie. Nouvelles Annales du Muséum d'Histoire Naturelle, Paris 4, 233–96.Google Scholar
Efimov, V. M., Rogov, M. A., Khudolei, A. K., Verzhbitsky, V. E., Tuchkova, M. I. & Zdobin, D. Y. 2010. The first valid find of ichthyosaur remains in the Middle Triassic of northern Siberia. In Podobina, V. M. (ed) Evolyutsiya zhizni na Zemle: materialy IV Mezhdunarodnogo simpoziuma (IV International Symposium on the Evolution of Life on the Earth, 10–12 November 2010), 343–45. Tomsk: TML Press. [In Russian.]Google Scholar
Egorov, A. Y., Bogomolov, Y. A., Konstantinov, A. G. & Kurushin, N. I. 1987. Stratigraphy of Triassic deposits of Kotel'nyi Island (New Siberian Islands). In Dagys, A. S. (ed.) Boreal Triassic, 66–80. Moscow: Nauka. [In Russian.]Google Scholar
Ekeheien, C. P., Delsett, L. L., Roberts, A. J. & Hurum, J. H. 2018. Preliminary report on ichthyopterygian elements from the Early Triassic (Spathian) of Spitsbergen. Norwegian Journal of Geology 98, 219–37.Google Scholar
Engelschiøn, V. S., Delsett, L. L., Roberts, A. J. & Hurum, J. H. 2018. Large-sized ichthyosaurs from the lower Saurian Niveau of the Vikinghøgda Formation (Early Triassic), Marmierfjellet, Spitsbergen. Norwegian Journal of Geology 98, 239–65.Google Scholar
Fischer, V., Bardet, N., Benson, R. B. J., Arkhangelsky, M. S. & Friedman, M. 2016. Extinction of fish-shaped marine reptiles associated with reduced evolutionary rates and global environmental volatility. Nature Communications 7, 10825.CrossRefGoogle ScholarPubMed
Fischer, V., Masure, E., Arkhangelsky, M. S. & Godefroit, P. 2011. A new Barremian (Early Cretaceous) ichthyosaur from western Russia. Journal of Vertebrate Paleontology 31, 1010–25.CrossRefGoogle Scholar
Ford, D. P. & Benson, R. B. J. 2019. A redescription of Orovenator mayorum (Sauropsida, Diapsida) using high-resolution μCT, and the consequences for early amniote phylogeny. Papers in Palaeontology 5, 197–239.CrossRefGoogle Scholar
Fraas, E. 1891. Die ichthyosaurier der süddeutschen trias- und Jura-ablagemngen. Tübingen: H. Laupp. 81 pp.Google Scholar
Fraas, E. 1913. Ein unverdrückter ichthyosaurus-schädel. Jahreshefte des vereins für vaterländische. Naturkunde in Württemberg 69, 1–12.Google Scholar
Godefroit, P. 1993. Les grands ichthyosaures sinémuriens d'Arlon. Bulletin d’ Institute Royale des Sciences Naturelles Belge, Sciences de la Terre 63, 25–71.Google Scholar
Hanken, J. & Wake, D. B. 1993. Miniaturization of body size: organismal consequences and evolutionary significance. Annual Review of Ecology and Systematics 24, 501–19.CrossRefGoogle Scholar
Henderson, D. M. 2015. A new, nearly three-dimensional specimen of the skull and anterior body of the late Triassic ichthyosaur Macgowania janiceps (McGowan 1996) from northeastern British Columbia, Canada. In Bininda-Emonds, O. R. P., Powell, G. L., Jamniczky, H. A., Bauer, A. M. & Theodor, J. (eds) All animals are interesting: a festschrift in honour of Anthony P. Russell, 121–49. Oldenburg, Germany: BIS Verlag.Google Scholar
Huang, J.-D., Motani, R., Jiang, D.-Y., Ren, X.-X., Tintori, A., Rieppel, O., Zhou, M., Hu, Y.-C. & Zhang, R. 2020. Repeated evolution of durophagy during ichthyosaur radiation after mass extinction indicated by hidden dentition. Scientific Reports 10, 7798.CrossRefGoogle ScholarPubMed
Huang, J.-D., Motani, R., Jiang, D.-Y., Tintori, A., Rieppel, O., Zhou, M., Ren, X.-X. & Zhang, R. 2019. The new ichthyosauriform Chaohusaurus brevifemoralis (Reptilia, Ichthyosauromorpha) from Majiashan, Chaohu, Anhui Province, China. PeerJ 7, e7561.CrossRefGoogle ScholarPubMed
Jamniczky, H. A. 2008. Turtle carotid circulation: a character analysis case study. Biological Journal of the Linnean Society 93, 239–56.CrossRefGoogle Scholar
Ji, C., Jiang, D.-Y., Motani, R., Rieppel, O., Hao, W. & Sun, Z.-Y. 2016. Phylogeny of the Ichthyopterygia incorporating recent discoveries from south China. Journal of Vertebrate Paleontology 36, e1025956.CrossRefGoogle Scholar
Jiang, D.-Y., Motani, R., Huang, J.-D., Tintori, A., Hu, Y.-C., Rieppel, O., Fraser, N.C., Ji, C., Kelley, N. P., Fu, W.-L. & Zhang, R. 2016. A large aberrant stem ichthyosauriform indicating early rise and demise of ichthyosauromorphs in the wake of the end-Permian extinction. Scientific Reports 6, 26232.CrossRefGoogle ScholarPubMed
Jiang, D.-Y., Motani, R., Tintori, A., Rieppel, O., Ji, C., Zhou, M., Wang, X., Lu, H. & Li, Z.-G. 2020. Evidence supporting predation of 4-m marine reptile by Triassic megapredator. iScience 23, 101347.Google Scholar
Kear, B. P. 2005. Cranial morphology of Platypterygius longmani Wade, 1990 (Reptilia: Ichthyosauria) from the lower cretaceous of Australia. Zoological Journal of the Linnean Society 145, 583–622.Google Scholar
Kelley, N. P., Motani, R., Jiang, D.-Y., Rieppel, O. & Schmitz, L. 2014. Selective extinction of Triassic marine reptiles during long-term sea-level changes illuminated by seawater strontium isotopes. Palaeogeography, Palaeoclimatology, Palaeoecology 400, 9–16.CrossRefGoogle Scholar
Konstantinov, A. G. 2018a. Orientosirenites, a new ammonoid genus (Sirenitidae; Ammonoidea) from the Upper Carnian of the Boreal Realm. Paleontological Journal 52, 18–26.Google Scholar
Konstantinov, A. G. 2018b. The Yakutosirenites armiger ammonoid zone of northeast Asia as a reference level of the Boreal-Tethyan correlation of the lower Carnian. Stratigraphy and Geological Correlation 26, 387–402.CrossRefGoogle Scholar
Konstantinov, A. G. 2019a. Ammonoids of the genus Yakutosirenites from the Carnian stage of northeast Asia. Stratigraphy and Geological Correlation 27, 234–47.CrossRefGoogle Scholar
Konstantinov, A. G. 2019b. A new ammonoid zone of the upper Carnian substage in northeastern Russia. Russian Journal of Pacific Geology 13, 522–34.CrossRefGoogle Scholar
Konstantinov, A. G., Sobolev, E. S. & Klets, T. V. 2003. New data on the fauna and biostratigraphy of Norian deposits of Kotel'nyi Island (New Siberian Islands). Stratigraphy and Geological Correlation 11, 231–43.Google Scholar
Laurenti, J. N. 1768. Specimen medicum: exhibens synopsin reptilium emendatam cum experimentis circa venena et antidota reptilium austriacorum. Vienna: Joan Thomae. 214 pp.CrossRefGoogle Scholar
Li, C. 1999. Ichthyosaur from Guizhou, China. China Science Bulletin 44, 1329–33.CrossRefGoogle Scholar
Lu, H., Jiang, D.-Y., Motani, R., Ni, P.-G., Sun, Z.-Y., Tintori, A., Xiao, S.-Z., Zhou, M., Ji, C. & Fu, W.-L. 2018. Middle Triassic Xingyi fauna: showing turnover of marine reptiles from coastal to oceanic environments. Palaeoworld 27, 107–16.CrossRefGoogle Scholar
Lucas, S. G. 2002. Toretocnemus, a late Triassic ichthyosaur from California, U.S.A. and Sonora, Mexico. New Mexico Museum of Natural History and Science Bulletin 21, 275–78.Google Scholar
Lucas, S. G. & González-León, C. M. 1995. Ichthyosaurs from the Upper Triassic of Sonora and the biochronology of Triassic ichthyosaurs. Geological Society of America, Special Paper 301, 17–20.Google Scholar
Maisch, M. W. 2001. Observations on Triassic ichthyosaurs. Part VII. New data on the osteology of Chaohusaurus geishanensis Young and Dong, 1972 from the Lower Triassic of Anhui (China). Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen 219, 305–27.CrossRefGoogle Scholar
Maisch, M. W. 2002. A braincase of Temnodontosaurus cf. trigonodon (von Theodori, 1843) (Ichthyosauria) from the lower Jurassic of Germany. Geologica et Palaeontologica 36, 115–22.Google Scholar
Maisch, M. W. 2020. The best-preserved skeleton of Suevoleviathan integer (Bronn, 1844) (Reptilia: Ichthyosauria) from the lower Jurassic of south-western Germany, with a discussion of the genus. Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen 297, 153–72.CrossRefGoogle Scholar
Maisch, M. W. & Ansorge, J. 2004. The Liassic ichthyosaur Stenopterygius cf. quadriscissus from the lower Toarcian of Dobbertin (northern Germany) and some considerations on lower Toarcian marine reptile paleobiogeography. Paläontologische Zeitschrift 78, 161–71.CrossRefGoogle Scholar
Maisch, M. W. & Blomeier, D. 2009. Filling the gap – an ichthyosaur (Reptilia: Ichthyosauria) from the middle Triassic Botneheia formation of Svalbard. Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen 254, 379–84.CrossRefGoogle Scholar
Maisch, M. W, Jiang, D.-Y., Hao, W.-C., Sun, Y.-L., Sun, Z.-Y. & Stöhr, H. 2008. A well-preserved skull of Qianichthyosaurus zhoui Li, 1999 (Reptilia: Ichthyosauria) from the Upper Triassic of China and the phylogenetic position of the Toretocnemidae. Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen 248, 257–66.CrossRefGoogle Scholar
Maisch, M. W. & Matzke, A. 1997a. Observations on Triassic ichthyosaurs. Part I: structure of the palate and mode of tooth implantation in Mixosaurus cornalianus (Bassani, 1886). Neues Jahrbuch für Geologie und Paläontologie. Monatshefte 1997, 717–32.CrossRefGoogle Scholar
Maisch, M. W. & Matzke, A. 1997b. Mikadocephalus gracilirostris n. gen., n. sp., a new ichthyosaur from the Grenzbitumenzone (Anisian-Ladinian) of Monte San Giorgio (Switzerland). Paläiontologische Zeitschrift 71, 267–89.CrossRefGoogle Scholar
Maisch, M. W. & Matzke, A. T. 2000.The Ichthyosauria. Stuttgarter Beiträge zur Naturkde. Serie B (Geologie und Paläontologie) 298, 1–159.Google Scholar
Maisch, M. W. & Matzke, A. 2006. The braincase of Phantomosaurus neubigi (Sander, 1997), an unusual ichthyosaur from the Middle Triassic of Germany. Journal of Vertebrate Paleontology 26, 598–607.Google Scholar
Marek, R., Moon, B. C., Williams, M. & Benton, M. J. 2015. The skull and endocranium of a Lower Jurassic ichthyosaur based on digital reconstructions. Palaeontology 58, 723–42.CrossRefGoogle Scholar
Martin, J. E., Fischer, V., Vincent, P. & Suan, G. 2012. A longirostrine Temnodontosaurus (Ichthyosauria) with comments on Early Jurassic ichthyosaur niche partitioning and disparity. Palaeontology 55, 995–1005.CrossRefGoogle Scholar
Martindale, R. C., Corsetti, F. A., James, N. P & Bottjer, D. J. 2015. Paleogeographic trends in Late Triassic reef ecology from northeastern Panthalassa. Earth-Science Reviews 142, 18–37.CrossRefGoogle Scholar
Maxwell, E. E. 2010. Generic reassignment of an ichthyosaur from the Queen Elizabeth Islands, northwest territories, Canada. Journal of Vertebrate Paleontology 2, 403–15.CrossRefGoogle Scholar
Maxwell, E. E., Dick, D., Padilla, S. & Parra, M. L. 2016. A new ophthalmosaurid ichthyosaur from the early cretaceous of Colombia. Papers in Palaeontology 2, 59–70.CrossRefGoogle Scholar
McGowan, C. 1973. The cranial morphology of the Lower Liassic latipinnate ichthyosaurs of England. Bulletin of the British Museum (Natural History), Geology 24, 1–109.CrossRefGoogle Scholar
McGowan, C. 1994. A new species of Shastasaurus (Reptilia: Ichthyosauria) from the Triassic of British Columbia. The most complete exemplar of the genus. Journal of Vertebrate Paleontology 14, 168–79.CrossRefGoogle Scholar
McGowan, C. 1995. A remarkable small ichthyosaur from the Upper Triassic of British Columbia, representing a new genus and species. Canadian Journal of Earth Sciences 32, 292–303.CrossRefGoogle Scholar
McGowan, C. 1996. A new and typically Jurassic ichthyosaur from the Upper Triassic of British Columbia. Canadian Journal of Earth Sciences 33, 24–32.CrossRefGoogle Scholar
McGowan, C. 1997. Chapter 3 – a transitional ichthyosaur fauna. In Callaway, J. M. & Nicholls, E. L. (eds) Ancient marine reptiles, 61–80. San Diego, California: Academic Press.CrossRefGoogle Scholar
McGowan, C. & Motani, R. 1999. A reinterpretation of the Upper Triassic ichthyosaur Shonisaurus. Journal of Vertebrate Paleontology 19, 42–49.CrossRefGoogle Scholar
McGowan, C. & Motani, R. 2003. Handbook of paleoherpetology, part 8, Ichthyopterygia. Munich: Verlag Dr. Friedrich Pfeil.Google Scholar
Merriam, J. C. 1895. On some reptilian remains from the Triassic of northern California. American Journal of Science, 2nd Series 50, 55–57.CrossRefGoogle Scholar
Merriam, J. C. 1902. Triassic Ichthyopterygia from California and Nevada. University of California Publications, Bulletin of the Department of Geology 3, 63–108.Google Scholar
Merriam, J. C. 1903. New Ichthyosauria from the Upper Triassic of California. University of California Publications, Bulletin of the Department of Geology 3, 249–63.Google Scholar
Merriam, J. C. 1908. Triassic Ichthyosauria, with special reference to the American forms. Memoirs of the University of California 1, 1–196.Google Scholar
Miedema, F. & Maxwell, E. E. 2019. Ontogeny of the braincase in Stenopterygius (Reptilia, Ichthyosauria) from the Lower Jurassic of Germany. Journal of Vertebrate Paleontology 39, e1675164.CrossRefGoogle Scholar
Moon, B. C. 2019. A new phylogeny of ichthyosaurs (Reptilia: Diapsida). Journal of Systematic Palaeontology 17, 129–55.CrossRefGoogle Scholar
Moon, B. C. & Kirton, A. M. 2016. Ichthyosaurs of the British middle and Upper Jurassic. Part 1. Ophthalmosaurus. Monographs of the Palaeontographical Society, London 170, 1–84.CrossRefGoogle Scholar
Moon, B. C. & Stubbs, T. L. 2020. Early high rates and disparity in the evolution of ichthyosaurs. Communications Biology 3, 68.CrossRefGoogle ScholarPubMed
Motani, R. 1999. Phylogeny of the Ichthyopterygia. Journal of Vertebrate Paleontology 19, 473–96.CrossRefGoogle Scholar
Motani, R. 2002a. Swimming speed estimation of extinct marine reptiles. I. Energetic approach revisited. Paleobiology 28, 251–62.2.0.CO;2>CrossRefGoogle Scholar
Motani, R. 2002b. Scaling effects in caudal fin propulsion and the speed of ichthyosaurs. Nature 415, 309–12.CrossRefGoogle Scholar
Motani, R. 2005. Evolution of fish-shaped reptiles (Reptilia: Ichthyopterygia) in their physical environments and constraints. Annual Review of Earth and Planetary Sciences 33, 395–420.CrossRefGoogle Scholar
Motani, R. 2008. Combining uniformitarian and historical data to interpret how earth environment influenced the evolution of Ichthyopterygia. The Paleontological Society Papers. 14,147–64.CrossRefGoogle Scholar
Motani, R., Ji, C., Tomita, T., Kelley, N., Maxwell, E., Jiang, D.-Y. & Sander, P. M. 2013. Absence of suction feeding ichthyosaurs and its implications for Triassic mesopelagic paleoecology. PLOS ONE 8, e66075.CrossRefGoogle ScholarPubMed
Motani, R, Jiang, D.-Y., Chen, G. B., Tintori, A., Rieppel, O., Ji, C. & Huang, J.-D. 2015. A basal ichthyosauriform with a short snout from the Lower Triassic of China. Nature 517, 485–88.Google ScholarPubMed
Motani, R., Jiang, D.-Y., Tintori, A., Ji, C. & Huang, J.-D. 2017. Pre- versus post-mass extinction divergence of Mesozoic marine reptiles dictated by time-scale dependence of evolutionary rates. Proceedings of the Royal Society B: Biological Sciences 284, 20170241.CrossRefGoogle ScholarPubMed
Müller, J., Sterli, J. & Anquetin, J. 2011. Carotid circulation in amniotes and its implications for turtle relationships. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 261, 289–97.Google Scholar
Nicholls, E. L. & Manabe, M. 2001. A new genus of ichthyosaur from the Late Triassic Pardonet Formation of British Columbia: bridging the Triassic-Jurassic gap. Canadian Journal of Earth Sciences 38, 983–1002.CrossRefGoogle Scholar
Nicholls, E. L. & Manabe, M. 2004. Giant ichthyosaurs from the Triassic – a new species of Shonisaurus from the Pardonet Formation (Norian: Late Triassic) of British Columbia. Journal of Vertebrate Palaeontology 24, 838–49.CrossRefGoogle Scholar
Nicholls, E. L., Wei, C. & Manabe, M. 2002. New material of Qianichthyosaurus Li, 1999 (Reptilia, Ichthyosauria) from the Late Triassic of Southern China, and implications for the distribution of Triassic ichthyosaurs. Journal of Vertebrate Paleontology 22, 759–65.CrossRefGoogle Scholar
Owen, R. 1881. A monograph of the fossil Reptilia of the Liassic formations. Part III. London: Palaeontographical Society.Google Scholar
Owen, R. 1860. On the orders of fossil and recent Reptilia, and their distribution in time. Report of the British Association for the Advancement of Science 29, 153–166.Google Scholar
Peabody, F. E. 1952. Petrolacosaurus kansensis Lane, a Pennsylvanian reptile from Kansas. The University of Kansas Paleontological Contributions, Series Vertebrata 1, 1–41.Google Scholar
Repossi, E. 1902: Il mixosauro degli strati Triassici di besano in Lombardia. Atti della Società Italiana di Scienze Naturali e del Museo civica di Storia naturale in Milano. 41, 361–72.Google Scholar
Rollot, Y., Evers, S. W., Joyce, W. G. 2021. A review of the carotid artery and facial nerve canal systems in extant turtles. PeerJ 8, e10475.CrossRefGoogle ScholarPubMed
Romer, A. S. 1968. An ichthyosaur skull from the cretaceous of Wyoming. University of Wyoming Contributions in Geology 7, 27–41.Google Scholar
Sander, P. M. 1989. The large ichthyosaur Cymbospondylus buchseri, sp. nov., from the Middle Triassic of Monte San Giorgio (Switzerland), with a survey of the genus in Europe. Journal of Vertebrate Paleontology 9, 163–73.CrossRefGoogle Scholar
Sander, P. M. 1992. Cymbospondylus (Shastasauridae: Ichthyosauria) from the Middle Triassic of Spitsbergen: filling a paleobiogeographic gap. Journal of Paleontology 66, 332–37.CrossRefGoogle Scholar
Schmitz, L., Sander, P. M., Storrs, G. W. & Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica Abteilung A 270, 133–62.CrossRefGoogle Scholar
Sennikov, A. G. 2001. Discovery of a primitive sauropterygian from the Lower Triassic of the Donskaya Luka (Don Basin) and the range of Triassic marine reptiles in Russia. Paleontological Journal 35, 301–9.Google Scholar
Sennikov, A. G., Arkhangelsky, M. S. 2010. On a typical Jurassic sauropterygian from the Upper Triassic of Wilczek Land (Franz Josef Land, Arctic Russia). Paleontological Journal 44, 567–72.CrossRefGoogle Scholar
Storrs, G. W., Arkhangel'skii, M. S. & Efimov, V. M. 2000. Mesozoic marine reptiles of Russia and other former Soviet republics. In Benton, M., Shishkin, M. A., Unwin, D. M. & Kurochkin, E. N. (eds.) The age of dinosaurs in russia and Mongolia, 187–210. Cambridge: Cambridge University Press.Google Scholar
Thorne, P. M., Ruta, M. & Benton, M. J. 2011. Resetting the evolution of marine reptiles at the Triassic–Jurassic boundary. Proceedings of the National Academy of Sciences of the United States of America 108, 8339–44.Google ScholarPubMed
von Huene, F. 1916. Beitrage zur kennhus der ichthyosaurier im deutschen muschelkalk. Palaeontographica 62, 1–68.Google Scholar
Wiman, C. 1912. Über Mixosaurus cornalianus Bass. sp. Bulletin of the Geological Institution of the University of Uppsala 11, 230–41.Google Scholar
Wiman, C. 1933. Über Grippia longirostris. Nova Acta Regiae Societatis Scientiarum Upsaliensis 9, 1–20.Google Scholar
Yang, P., Ji, C., Jiang, D., Motani, R., Tintori, A., Sun, Y. & Sun, Z. 2013. A new species of Qianichthyosaurus (Reptilia: Ichthyosauria) from Xingyi fauna (Ladinian, Middle Triassic) of Guizhou. Acta Scientiarum Naturalium Universitatis Pekinensis 49, 1002–08.Google Scholar
Yin, G.-Z., Zhou, X.-G., Cao, Z.-T., Yu, Y.-Y. & Luo, Y.-M. 2000. A preliminary study on the early late Triassic marine reptiles from Guanling, Guizhou Province, China. Geology-Geochemistry 28, 1–25. [In Chinese with English summary.]Google Scholar
Zhou, M., Jiang, D.-Y., Motani, R., Tintori, A., Ji, C., Sun, Z.-Y., Ni, P.-G. & Lu, H. 2017. The cranial osteology revealed by three-dimensionally preserved skulls of the early triassic ichthyosauriform Chaohusaurus chaoxianensis (Reptilia: Ichthyosauromorpha) from Anhui, China. Journal of Vertebrate Paleontology 37, 4.CrossRefGoogle Scholar
Zverkov, N. G., Averianov, A. O. & Popov, E.V. 2018. Basicranium of an elasmosaurid plesiosaur from the Campanian of European Russia. Alcheringa: An Australasian Journal of Palaeontology 42, 528–42.CrossRefGoogle Scholar
Zverkov, N. G. & Efimov, V. M. 2019. Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm. Journal of Systematic Palaeontology 17, 1183–213.CrossRefGoogle Scholar
Zverkov, N. G. & Jacobs, M. L. 2021. Revision of Nannopterygius (Ichthyosauria: Ophthalmosauridae): reappraisal of the ‘inaccessible’ holotype resolves a taxonomic tangle and reveals an obscure ophthalmosaurid lineage with a wide distribution. Zoological Journal of the Linnean Society 191, 228–75.CrossRefGoogle Scholar
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