Teleosaurus

{{Short description|Extinct genus of reptiles}} {{Automatic taxobox | fossil_range = Bajocian–Bathonian, {{Fossil range|171|164}} | image = Teleosaurus cadomensis.png | image_caption = Holotype skull of ''T. cadomensis'' (MNHN AC 8746) seen from multiple angles | taxon = Teleosaurus | authority = Geoffroy, 1825 ''vide'' Cuvier, 1824 | type_species = {{extinct}}'''''Teleosaurus cadomensis''''' | type_species_authority = (Lamouroux, 1820) | subdivision_ranks = Other species | subdivision = *''T. geoffroyi''? Eudes-Deslongchamps, 1868c | synonyms = {{hidden|| *''Crocodylus cadomensis'' Lamouroux, 1820 *''Teleosaurus asthenodirus'' Owen, 1842 *''Teleosaurus brevior'' Owen, 1884 *''Teleosaurus eucephalus'' Seeley, 1880 *''Teleosaurus gladius'' Eudes-Deslongchamps, 1868c *''Teleosaurus lacunosae'' Quenstedt, 1858 *''Teleosaurus latifrons'' Owen, 1884 *''Teleosaurus minimus'' Quenstedt, 1852 *''Teleosaurus ornati'' Quenstedt, 1852 *''Teleosaurus soemmeringii'' Holl, 1829 *''Teleosaurus subulidens'' Phillips, 1871 }} }}

'''''Teleosaurus''''' (from {{langx|el|τέλειος}} {{Transliteration|el|téleios}}, 'perfect' and {{langx|el|σαῦρος}} {{Transliteration|el|saûros}}, 'lizard')<ref>{{cite book |last1=Roberts |first1=George |title=An etymological and explanatory dictionary of the terms and language of geology |date=1839 |publisher=Longman, Orme, Brown, Green, & Longmans |location=London |page=169 |url=https://archive.org/details/anetymologicala00robegoog |access-date=1 January 2022 |language=English}}</ref> is an extinct genus of teleosaurid crocodyliform found in the Middle Jurassic Calcaire de Caen Formation of France.<ref>Weishampel, David B; et al. (2004). "Dinosaur distribution (Middle Jurassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 538–541. {{ISBN|0-520-24209-2}}.</ref> It was approximately {{convert|3|m|ft|0}} in length.<ref>P. H. Phizackerley (1951). A revision of the Teleosauridae in the Oxford University Museum and the British Museum. ''The Annals and Magazine of Natural History'' '''12'''(4): 1170–1192. </ref> The holotype is MNHN AC 8746, a quarter of a skull and other associated postcranial remains, while other fragmentary specimens are known.<ref name="Teleosauroidea">{{cite journal|last1=Johnson|first1=Michela M.|last2=Young|first2=Mark T.|last3=Brusatte|first3=Stephen L.|date=2020|title=The phylogenetics of Teleosauroidea (Crocodylomorpha, Thalattosuchia) and implications for their ecology and evolution|journal=PeerJ|volume=8|article-number=e9808|doi=10.7717/peerj.9808|pmid=33083104|pmc=7548081|doi-access=free}}</ref> The type species is '''''T. cadomensis''''',<ref name="Geoffroy1825" /> but a second species, ''T. geoffroyi'' may also exist.<ref>P. H. Phizackerley. (1951). A revision of the Teleosauridae in the Oxford University Museum and the British Museum. ''The Annals and Magazine of Natural History'' 12(4):1170-1192</ref> It was previously considered a wastebasket taxon, with many other remains assigned to the genus.<ref name="Johnson2019">{{cite web|date=2019|title=The taxonomy, systematics and ecomorphological diversity of Teleosauroidea (Crocodylomorpha, Thalattosuchia), and the evaluation of the genus 'Steneosaurus'|url=https://era.ed.ac.uk/handle/1842/36656|website=Archives of the University of Edinburgh|language=English|publication-date=}}</ref><ref name="Teleosauroidea" />

==History== thumb|left|Skull illustration [[File:Teleosaurus cadomensis FMNH.jpg|left|thumb|Dorsal osteoderms (NHMUK PV R 4207) of ''T. cadomensis'' from Normandy, which have been in the collection of the Field Museum of Natural History since 1914]] Teleosaur remains have been known to science since at least 1758,<ref>Chapman, W. (1758) An account of the fossile bones of an allegator, found on the sea-shore, near Whitby in Yorkshire. ''Philosophical Transactions of The Royal Society of London'' 50:688-691</ref><ref>Morton, C. and Wooler, M. (1758) A Description of the Fossil Skeleton of an Animal Found in the Alum Rock Near Whitby. ''Philosophical Transactions (1683–1775)'' 50:786-790</ref> although at first scientists believed the remains belonged to extinct crocodiles and alligators, and remains that have at one point in time been attributed to ''Teleosaurus'' (and ''Steneosaurus'') have been known to science since at least 1800.<ref>Cuvier, G. (1800) On a new species of fossil crocodile [in French] ''Bulletin de la Sociéte philomatique de Paris'' 2:159</ref><ref>Cuvier, G. (1808) On the fossil bones of crocodiles: and especially on those around Le Havre and Honfleur, with remarks on the skeletons of the saurians of Thuringia [in French] ''Annales du Muséum d'histoire naturelle'' 12:73-110</ref> The holotype was discovered during the early 19th century by Pierre Tesson before he traded it with Lamoroux. ''Teleosaurus'' was briefly noted on by Jean Vincent Félix Lamouroux in 1820 as ''Crocodilus cadomensis'' and then he sent the specimen to Georges Cuvier.<ref>Lamouroux, M (1820) Sur le crocodile fossile trouvé dans les carrières du Bourg d'Allemagne, a un quart de lieue de Caen. ''Annales générales des Sciences physiques''.</ref> It was fully described by Cuvier in 1824,<ref>Cuvier, G. (1824) Article IV Des os de deux espèces inconnues de Gavials; trouvés pêle-mêle près de Honfleur et du Hâvre. Sur les Ossemens Fossiles. ''Nouvelle édition, Tome Cinquieme, Partie 2 Paris: Dufour & d'Occagne.'' 143–160.</ref> but it was not published until a year later by Étienne Geoffroy Saint-Hilaire.<ref name=Geoffroy1825>Geoffroy Saint-Hilaire, É. (1825) Recherches sur l'organisation des gavials. ''Mém Mus Natl Hist Nat'' 12: 97–155.</ref>

The second species attributed to ''Teleosaurus'', ''T. soemmeringii'' (now a synonym of ''T. cadomensis''), was named in 1829.<ref>F. Holl. (1829). Handbuch der Petrefactenkunde, mit einer Einleitung über die Vorwelt der organischen Wesen auf der Erde von Dr. Ludwig Choulant 1:1-115</ref> In 1842, ''T. asthenodeirus'', was named.<ref name=Owen1842 /> ''T. minimus'' and ''T ornati'' were named in 1852 and it is now firmly a synonym of ''T. cadomensis''.<ref>Von Quenstedt, F. A. (1852). ''Handbuch der Petrefaktenkunde.'' Tübingen: Laupp.</ref> Friedrich August von Quenstedt also added ''T. lacunosae'' several years later in 1858. Eudes-Deslongchamps followed in 1868, naming the two species ''T. geoffroyi'' and ''T. gladius'' - both are based on remains destroyed in Caen in 1944. ''T. geoffroyi'', described on the basis of now destroyed mandibular fragments, was considered a valid species by Vignaud (1995),<ref>Vignaud, P. (1995). "The Thalattosuchia, Mesozoic marine crocodiles: phylogenetic systematics, paleoecology, biochronology and palaeogeographical implications." ''Unpublished PhD thesis, University of Poitiers'' p.410</ref> but it was made a probable synonym of ''T. cadomensis'' in 2020.<ref name=Teleosauroidea /> Richard Owen added ''T. brevior'' and ''T. latifrons'' to ''Teleosaurus'' in 1884.<ref>R. Owen. (1884). A History of British Fossil Reptiles, Part III. 1-199</ref>

In 2019, the taxonomy of Teleosauroidea was reviewed and ''T. cadomensis'' was seen as the only valid species.<ref name=Johnson2019 /> The rest of the known species were absorbed into ''T. cadomensis'' or other genera.<ref name=Johnson2019 /><ref name=Teleosauroidea /> This study was published in October 2020.<ref name=Teleosauroidea />

==Description== ''Teleosaurus'' had highly elongate jaws, similar to those of a modern gharial.<ref name=Owen1842>R. Owen (1842). Report on British fossil reptiles, part II. ''Report of the British Association for the Advancement of Science'' '''11''': 60-204. </ref> It had a long, slender, body, with a sinuous tail that would have helped propel it through the water. Its forelimbs were remarkably short, and would probably have been held close to the body when swimming to improve the animal's streamlining. Unlike modern crocodilians, it lived in the open ocean, and it probably caught fish and squid with its sharp, needle-like teeth.<ref name=EoDP>{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|location=London|page= 99|isbn= 1-84028-152-9}}</ref>

=== Known remains === ''Teleosaurus cadomensis'' is known from the following specimens:<ref name="Teleosauroidea" />

* MNHN AC 8746 (holotype): quarter of a skull and other associated postcranial remains * NHMUK PV OR 119a: dorsal osteoderms * NHMUK PV R 4207: dorsal osteoderms * NHMUK PV OR 32588: dorsal, sacral and caudal vertebrae * NHMUK PV OR 32657: femur * NHMUK PV OR 32680: ischium * NHMUK PV OR 33124 mandibular symphysis * NHMUK PV OR 39788: partial rostrum * NHMUK PV R 880 and NHMUK PV R 880a: additional casts

==References== {{Portal|Paleontology}} {{Reflist}}

Category:Prehistoric pseudosuchian genera Category:Prehistoric marine crocodylomorphs Category:Middle Jurassic crocodylomorphs Category:Jurassic reptiles of Europe Category:Taxa named by Étienne Geoffroy Saint-Hilaire Category:Fossil taxa described in 1820 Category:Taxa named by Georges Cuvier