Recent descriptions of new taxa and recognition of survivorship of Jurassic genera across the Jurassic–Cretaceous boundary bring the total number of Cretaceous ichthyosaur genera to eight. Taxa currently known from the Cretaceous include Ophthalmosaurus, Caypullisaurus, Aegirosaurus, Platypterygius, Maiaspondylus, Athabascasaurus, Sveltonectes, and Acamptonectes. This review summarizes the occurrence of all Cretaceous genera. A discussion of morphological diversity demonstrates the different, though overlapping, ecological niches occupied by the different taxa, while the comparison of phylogenetic hypotheses shows the problems inherent in understanding the evolutionary relationships between Cretaceous genera. The Late Jurassic radiation indicated in the competing phylogenetic hypotheses may correlate with the opening of the Atlantic Ocean or additional dispersal routes established by the breakup of Gondwana. Inclusion of the stratigraphically oldest Platypterygius species may aid in resolving these evolutionary relationships.
References
[1]
Maisch, M.W.; Matzke, A.T. The Ichthyosauria. Stuttg. Beitr. Naturkunde Ser. B (Geolog. Pal？ontol.) 2000, 298, 1–159. in German.
[2]
McGowan, C.; Motani, R. Ichthyopterygia. Handbook of Paleoherpetology; Sues, H.D., Ed.; Verlag Dr. Friedrich Pfeil: Munich, Germany, 2003; Volume 8, p. 175.
[3]
Sander, P.M. Ichthyosauria: Their diversity, distribution, and phylogeny. Pal？ontol. Z. 2000, 74, 1–35.
[4]
Mazin, J.M.; Bardet, N.; Godefroit, P. The European Ichthyopterygia: A re-assessment. J. Vertebr. Paleontol. 1994, 14, 36–37.
[5]
Bardet, N. Dental cross-sections in Cretaceous Ichthyopterygia: Systematic implications. Geobios-LYON 1990, 23, 169–172, doi:10.1016/S0016-6995(06)80049-5.
[6]
Bardet, N. Stratigraphic evidence for the extinction of ichthyosaurs. Terra Nova 1992, 4, 649–656, doi:10.1111/j.1365-3121.1992.tb00614.x.
[7]
Broili, F. Ein neuer Ichthyosaurus aus der norddeutschen Kreide. Palaeontogr. 1907, 54, 139–152. in German.
[8]
Maxwell, E.E.; Caldwell, M.W. A new genus of ichthyosaur from the Lower Cretaceous of western Canada. Palaeontology 2006, 49, 1043–1052, doi:10.1111/j.1475-4983.2006.00589.x.
[9]
Druckenmiller, P.S.; Maxwell, E.E. A new Lower Cretaceous (lower Albian) ichthyosaur genus from the Clearwater Formation, Alberta, Canada. Can. J. Earth Sci. 2010, 47, 1037–1053, doi:10.1139/E10-028.
[10]
Fischer, V.; Masure, E.; Arkhangelsky, M.S.; Godefroit, P. A new Barremian (Early Cretaceous) ichthyosaur from western Russia. J. Vertebr. Paleontol. 2011, 31, 1010–1025, doi:10.1080/02724634.2011.595464.
[11]
Fischer, V.; Maisch, M.W.; Naisch, D.; Kosma, R.; Liston, J.; Joger, U.; Krüger, F.J.; Pardo Pérez, J.; Tainsh, J.; Appleby, R.M. New ophthalmosaurid ichthyosaurs from the European Lower Cretaceous demonstrate extensive ichthyosaur survival across the Jurassic-Cretaceous boundary. PloS ONE 2012, 7, 1–23.
[12]
Fischer, V. New ophthalmosaurids from Europe and Russia broaden the biodiversity of Early Cretaceous ichthyosaurs. J. Vertebr. Paleontol. Suppl. 2011, 31, 110.
[13]
McGowan, C. The systematics of Cretaceous ichthyosaurs with particular reference to the material from North America. Contrib. Geol. Univ. Wyo. 1972, 11, 9–29.
[14]
McGowan, C. Dinosaurs, Spitfires, and Seadragons, 1st ed.; Harvard University Press: Cambridge, MA, USA, 1991; p. 365.
[15]
Fischer, V. New data on the ichthyosaur Platypterygius hercynicus and its implications for the validity of the genus. Acta Palaeontol. Pol. 2012, 57, 123–134, doi:10.4202/app.2011.0007.
[16]
Kolb, C.; Sander, P.M. Redescription of the ichthyosaur Platypterygius hercynicus (Kuhn 1946) from the Lower Cretaceous of Salzgitter (Lower Saxony, Germany). Palaeontogr. Abt. A. 2009, 288, 151–192.
[17]
Arkhangelsky, M.S.; Averianov, A.O.; Pervushov, E.M.; Tarnikow, V.Y.; Zozyrev, N.Y. On ichthyosaur remains from the Cretaceous of the Voronezh Region. Palaeontol. J. 2008, 42, 287–291, doi:10.1134/S0031030108030106.
[18]
Von Huene, F. Beitrag zur Kenntnis mariner mesozoischer Wirbeltiere in Argentina. Zent. Mineral. Geolog. Pal？ontol. B 1927, 1927, 22–29. in German.
[19]
Fernández, M.; Aguirre-Urreta, M.B. Revision of Platypterygius hauthali von Huene, 1927 (Ichthyosauria: Ophthalmosauridae) from the Early Cretaceous of Patagonia, Argentin. J. Vertebr. Paleontol. 2005, 25, 583–587, doi:10.1671/0272-4634(2005)025[0583:ROPHVH]2.0.CO;2.
[20]
Pardo Pérez, J.; Frey, E.; Stinnesbeck, W.; Salazar, C.; Leppe, M. Life and death on the Torres del Pain ichthyosaurs, southern Chile. In Proceedings of 7th Annual Meeting of the European Association of Vertebrate Palaeontologists, Berlin, Germany, 20-24 July 2009; p. 55.
[21]
Pardo Pérez, J.M.; Frey, E.; Stinnesbeck, W.; Rivas, L. Early Cretaceous ichthyosaurs from the Tyndall Glacier in Torres Del Paine National Park, southernmost Chile. J. Vertebr. Paleontol. Suppl. 2011, 31, 171.
[22]
Pardo-Pérez, J.; Frey, E.; Stinnesbeck, W.; Fernánez, M.S.; Rivas, L.; Salazar, C.; Leppe, M. An ichthyosaurian forefin from the Lower Cretaceous Zapata Formation of southern Chile: Implicaitons for morphological variability within Platypterygius. Palaeobio. Palaeoenv., 2012. in submission.
[23]
Maxwell, E.E.; Kear, B.P. Postcranial anatomy of Platypterygius americanus (Reptilia: Ichthyosauria) from the Cretaceous of Wyoming. J. Vertebr. Paleontol. 2010, 30, 1059–1068, doi:10.1080/02724634.2010.483546.
[24]
McCoy, F. On the occurrence of Ichthyosaurus and Plesiosaurus in Australia. J. Nat. Hist. Third Ser. 1867, 19, 355–356.
[25]
McCoy, F. On the discovery of Enaliosauria and other Cretaceous fossils in Australia. Trans. Proc. Rol. Soc. Vic. 1867, 8, 41–42.
[26]
Zammit, M. A review of Australasian ichthyosaurs. Alcheringa 2010, 34, 281–292.
[27]
Etheridge, R. On additional evidence of the genus Ichthyosaurus in the Mesozoic rocks (“Rolling Downs Formation”) of north-eastern Australia. P. Linn. Soc. N. S. W. 1888, 2, 405–409.
[28]
Wade, M. A review of the Australian Cretaceous longipinnate ichthyosaur Platypterygius (Ichthyosauria, Ichthyopterygia). Mem. Qld. Mus. 1990, 28, 115–137.
[29]
Kear, B.P. Cretaceous marine reptiles of Australia: A review of taxonomy and distribution. Cretaceous Res. 2003, 24, 277–303, doi:10.1016/S0195-6671(03)00046-6.
[30]
Smith, A.G.; Smith, D.G.; Funnell, B.M. Atlas of Mesozoic and Cenozoic Coastlines; Cambridge University Press: Cambridge, UK, 1994; p. 99.
[31]
Carter, J. Notice of the jaws of an Ichthyosaurus from the chalk in the neighbourhood of Cambridge. Rep. Br. Assoc. Advanc. Sci. 1845, 1845, 60.
[32]
Carter, J. On the occurrence of a new species of Ichthyosaurus in the chalk. Lond. Geol. J. Rec. Discov. Br. Foreign Paleontol. 1846, 1, 7–9.
[33]
Owen, R. A monograph on the fossil Reptilia of the Cretaceous formations. Palaeontogr. Soc. Monogr. 1851, 5, 1–118.
[34]
Kiprijanoff, W. Studien über die fossilen Reptilien Russlands. Theil 1. Gattung Ichthyosaurus Konig aus dem Sewerischen Sandstein oder Kreide-Gruppe. Mém. Acad. Imp. Sci. St.-Pétersbg. 7e Sér. 1881, 28, 1–103. in German.
[35]
Storrs, G.W.; Arkhangelsky, M.S.; Efimov, V.M. Mesozoic marine reptiles of Russia and other former Soviet Republics. In The Age of Dinosaurs in Russia and Mongolia; Benton, M.J., Shishkin, M.A., Unwin, D.M., Kurochkin, E.N., Eds.; Cambridge University Press: Cambridge, UK, 2000; pp. 187–210.
[36]
Diedrich, C. New ichthyosaur remains of Platypterygius cf. campylodon (Carter 1846) (Ichthyopterygia, Reptilia) from the Cenomanian of NW Germany. Munstersche Forschungen Geol. Palaontol. 2002, 93, 97–108.
[37]
Nace, R.L. A new ichthyosaur from the Upper Cretaceous Mowry formation of Wyoming. Am. J. Sci. 1939, 237, 673–686, doi:10.2475/ajs.237.9.673.
[38]
Nace, R.L. A new ichthyosaur from the Late Cretaceous, Northeast Wyoming. Am. J. Sci. 1941, 239, 908–914, doi:10.2475/ajs.239.12.908.
[39]
Kuhn, O. Ein Skelett von Ichthyosaurus (Platypterygius) hercynicus n. sp. aus dem Aptium von Gitter. Ber. Naturforschenden Ges. Bamb. 1946, 29, 69–82. in German.
[40]
Páramo, M.E. Platypterygius sachicarum (Reptilia, Ichthyosauria) neuva especie del Cretacico de Colombia. Rev. Ingeominas 1997, 6, 1–12. in Spanish.
[41]
Lydekker, R. Indian Pre-Tertiary vertebrate fossil Reptilia and Batrachia. Mem. Geolog. Surv. India 1879, 1, 1–36.
[42]
Underwood, C.J.; Goswami, A.; Prasad, G.V.R.; Verma, O.; Flyn, J.J. Marine vertebrates from the ‘middle’ Cretaceous (early Cenomanian) of south India. J. Vertebr. Paleontol. 2011, 31, 539–552, doi:10.1080/02724634.2011.574518.
[43]
Sirotti, A.; Papazzoni, C. On the Cretaceous ichthyosaur remains from the Northern Apennines (Italy). Boll. Soci. Paleontol. Ital. 2002, 41, 237–248.
[44]
Sachs, S.; Grant-Mackie, J.A. An ichthyosaur fragment from the Cretaceous of Northland, New Zealand. J. Royal Soc. New Zealand 2003, 33, 307–314, doi:10.1080/03014223.2003.9517732.
[45]
Bardet, N.; Wellnhofer, P.; Herm, D. Discovery of ichthyosaur remains (Reptilia) in the Upper Cenomanian of Bavaria. Mitt. Bayer. Staatssamml. Pal？ontol. Hist. Geol. 1994, 34, 213–220.
[46]
Maxwell, E.E.; Caldwell, M.W. Evidence for a second species of the ichthyosaur Platypterygius in North America: A new record from the Loon River Formation (Lower Cretaceous) of Northwestern Canada. Can. J. Earth Sci. 2006, 43, 1291–1295, doi:10.1139/e06-029.
[47]
Adams, T.L.; Fiorillo, A. Platypterygius Huene, 1922 (Ichthyosauria, Ophthalmosauridae) from the Late Cretaceous of Texas, USA. Palaeontol. Electron. 2010, 14, 12.
[48]
Maxwell, E.E.; Kear, B.P. Postcranial anatomy of Platypterygius americanus (Reptilia: Ichthyosauria) from the Cretaceous of Wyoming. J. Vertebr. Paleontol. 2010, 30, 1059–1068, doi:10.1080/02724634.2010.483546.
[49]
Zammit, M.; Norris, R.M.; Kear, B.P. The Australian Cretaceous ichthyosaur Platypterygius australis: A description and review of postcranial remains. J. Vertebr. Paleontol. 2010, 30, 1726–1735, doi:10.1080/02724634.2010.521930.
[50]
Choo, B. Cretaceous ichthyosaurs from Western Australia. Rec. West. Aust. Mus. Suppl. 1999, 57, 207–218.
[51]
Kear, B.P. Biogeographic and biostratigraphic implications of Australian Mesozoic marine reptiles. Aust. Biologist 2004, 17, 4–22.
[52]
Lydekker, R. Catalogue of the fossil Reptilia and Amphibia in the British Museum (Natural History). Part II. Containing the Orders Ichthyopterygia and Sauropterygia; Trustees of the British Museum: London, UK, 1889; p. 307.
[53]
McGowan, C. Further evidence for the wide geographical distribution of ichthyosaur taxa (Reptilia: Ichthyosauria). J. Paleontol. 1978, 52, 1155–1162.
[54]
Spalletti, L.; Gasparini, Z.; Veiga, G.; Schwarts, E.; Fernández, M.; Matheos, S. Facies anóxicas, procesos deposicionales y herpetofauna de la rampa marina titoniano-berriasisana en la Cuenca Neuqina (Yesera del Tromen), Neuquén, Argentina. Rev. Geológ. Chile 1999, 26, 109–123. in Spanish.
[55]
Fischer, V.; Clément, A.; Guiomar, M.; Godefroit, P. The first definite record of a Valanginian ichthyosaur and its implications on the evolution of post-Liassic Ichthyosauria. Cretaceous Res. 2011, 32, 155–163, doi:10.1016/j.cretres.2010.11.005.
[56]
Scheyer, T.M.; Moser, M. Survival of the thinnest: rediscovery of Bauer’s (1898) ichthyosaur tooth sections from Upper Jurassic lithographic limestone quarries, south Germany. Swiss J. Geosci. 2011, 104, 147–157, doi:10.1007/s00015-011-0076-y.
[57]
Bardet, N.; Fernández, M. A new ichthyosaur from the upper Jurassic lithographic limestones of Bavaria. J. Paleontol. 2000, 74, 503–511, doi:10.1666/0022-3360(2000)074<0503:ANIFTU>2.0.CO;2.
[58]
Ensom, P.C.; Clements, R.G.; Feist-Brukhardt, S.; Milner, A.R.; Chitolie, J.; Jeffery, P.A.; Jones, C. The age and identity of an ichthyosaur reputedly from the Purbeck Limestone Group, Lower Cretaceous, Dorset, southern England. Cretaceous Res. 2009, 30, 699–709, doi:10.1016/j.cretres.2008.12.005.
[59]
Massare, J.A. Tooth morphology and prey preference of Mesozoic marine reptiles. J. Vertebr. Paleontol. 1987, 7, 121–137, doi:10.1080/02724634.1987.10011647.
[60]
Massare, J.A. Faunas, behavior, and evolution. In Ancient Marine Reptiles, 2nd; Callaway, J.M., Nicholls, E.L., Eds.; Academic Press: San Diego, CA, USA, 1997; pp. 401–421.
[61]
Gilmore, C.W. Discovery of teeth in Baptanodon, an ichthyosaurian from the Jurassic of Wyoming. Science 1902, 16, 913–914.
[62]
Buchy, M.C. First record of Ophthalmosaurus (Reptilia: Ichthyosauria) from the Tithonian (Upper Jurassic) of Mexico. J. Paleontol. 2010, 84, 149–155, doi:10.1666/08-122.1.
[63]
Kirton, A.J. A Review of British Upper Jurassic Ichthyosaurs. Ph.D. Dissertation, University of Newcastle-upon-Tyne, Newcastle-upon-Tyne, Tyne, Wear, UK, 1981.
[64]
Fernández, M.S. A new ichthyosaur from the Tithonian (Late Jurassic) of the Neuquén Basin, Northwestern Patagonia, Argentina. J. Paleontol. 1997, 71, 479–484.
[65]
Fernández, M. Nuevo material de Caypullisaurus bonapartei Fernández (Reptilia: Ichthyosauridae) del Jurásico superior de la Cuenca Neuquina, Argentina. Ameghiniana 1998, 35, 21–24. in Spanish.
[66]
Kear, B.P. Cranial morphology of Platypterygius longmani Wade, 1990 (Reptilia: Ichthyosauria) from the Lower Cretaceous of Australia. Zool. J. Linn. Soc-Lond. 2005, 145, 583–622, doi:10.1111/j.1096-3642.2005.00199.x.
[67]
Kear, B.P.; Boles, W.E.; Smith, E.T. Unusual gut contents in a Cretaceous ichthyosaur. Proc. Roy. Soc. Lond. Biol. Lett. Suppl. 2003, 270, 206–208.
[68]
Kear, B.P.; Barrett, P. Reassessment of the English Cretaceous ichthyosaur Platypterygius campylodon. In Proceedings of Symposium of Vertebrate Palaeontology and Comparative Anatomy, Glasgow, UK, August–September 2007; p. 38.
[69]
Bennett, S.P.; Barrett, P.M.; Collinson, M.E.; Moore-Fay, S.; Davis, P.G.; Palmer, C.P. A new Specimen of Ichthyosaurus communis from Dorset, UK, and its bearing on the stratigraphical range of the species. P. Geologist. Assoc. 2012, 123, 146–154, doi:10.1016/j.pgeola.2011.07.001.
[70]
Lawrence, J.D. A Total Evidence Analysis of the Evolutionary History of the Thunnosaur Ichthyosaurs. M.Sc. Thesis, Graduate College of Bowling Green State University, Bowling Green, OH, USA, 2008.
[71]
Gasparini, Z.; Fernández, M. 1997. Tithonian marine reptiles of the eastern Pacific. In Ancient Marine Reptiles, 2nd Edition; Calloway, J.M., Nichols, E.L., Eds.; Academic Press: San Diego, CA, USA, 1997; pp. 223–253.
