Metriorhynchidae
{{Short description|Extinct family of reptiles}}
{{Automatic taxobox
| name = Metriorhynchids
| fossil_range = Middle Jurassic-Early Cretaceous, {{fossil_range|168|125}}
| image = Cricosaurus albersdoerferi.jpg
| image_upright = 1.2
| image_caption = Fossil of Cricosaurus, Museum Eichstaett
| taxon = Metriorhynchidae
| subdivision_ranks = Genera
| subdivision =
- {{extinct}}Metriorhynchinae Lydekker, 1888
- {{extinct}}Enalioetes
- {{extinct}}Gracilineustes
- {{extinct}}Maledictosuchus
- {{extinct}}Metriorhynchus
- {{extinct}}Thalattosuchus
- {{extinct}}Rhacheosaurini Young et al., 2011
- {{extinct}}Cricosaurus
- {{extinct}}Rhacheosaurus
- {{extinct}}Geosaurinae Bonaparte, 1845
- {{extinct}}Neptunidraco
- {{extinct}}Geosaurini Bonaparte, 1845
- {{extinct}}Aggiosaurus
- {{extinct}}Dakosaurus
- {{extinct}}Purranisaurus
- {{extinct}}Torvoneustes
- {{extinct}}Tyrannoneustes
- {{extinct}}Geosaurina Bonaparte, 1845
- {{extinct}}Geosaurus
- {{extinct}}Ieldraan
- {{extinct}}Plesiosuchina Young et al., 2014
- {{extinct}}Plesiosuchus
- {{extinct}}Suchodus
| synonyms =
- Geosauridae Andrews, 1913{{Cite book|last1=Andrews |first1=CW. |date=1913 |title=A descriptive catalogue of the marine reptiles of the Oxford Clay, Part Two |location=London |publisher=British Museum (Natural History) |pages=206}}
}}
Metriorhynchidae is an extinct family of specialized, aquatic metriorhynchoid crocodyliforms from the Middle Jurassic to the Early Cretaceous period (Bajocian to early Aptian{{cite journal|author=Alfio A. Chiarenza |author2=Davide Foffa |author3=Mark T. Young |author4=Gianni Insacco |author5=Andrea Cau |author6=Giorgio Carnevale |author7=Rita Catanzariti |year=2015 |title=The youngest record of metriorhynchid crocodylomorphs, with implications for the extinction of Thalattosuchia |journal=Cretaceous Research |volume=56 |pages=608–616 |doi=10.1016/j.cretres.2015.07.001 |bibcode=2015CrRes..56..608C |hdl=2318/1537833 |hdl-access=free }}) of Europe, North America and South America. The name Metriorhynchidae was coined by the Austrian zoologist Leopold Fitzinger in 1843.Fitzinger LJFJ. 1843. Systema Reptilium. Wien: Braumüller et Seidel, 106 pp. The group contains two subfamilies, the Metriorhynchinae and the Geosaurinae.{{cite journal|author1=Mark T. Young |author2=Marco Brandalise de Andrade |year=2009 |title=What is Geosaurus? Redescription of Geosaurus giganteus (Thalattosuchia: Metriorhynchidae) from the Upper Jurassic of Bayern, Germany |journal=Zoological Journal of the Linnean Society |volume=157 |issue=3 |pages=551–585 |doi=10.1111/j.1096-3642.2009.00536.x |doi-access=free }}{{cite journal|author1=Mark T. Young |author2=Stephen L. Brusatte |author3=Marcello Ruta |author4=Marco Brandalise de Andrade |year=2010 |title=The evolution of Metriorhynchoidea (Mesoeucrocodylia, Thalattosuchia): an integrated approach using geometrics morphometrics, analysis of disparity and biomechanics |journal=Zoological Journal of the Linnean Society |issue=4 |volume=158 |pages=801–859 |doi=10.1111/j.1096-3642.2009.00571.x |doi-access=free }} They represent the most marine adapted of all archosaurs.
Description
Metriorhynchids are fully aquatic crocodyliforms. Their forelimbs were small and paddle-like, and unlike living crocodylians, they lost their osteoderms ("armour scutes"). Their body shape maximised hydrodynamy (swimming efficiency), as they did have a shark-like tail fluke.{{cite journal | author = Fraas E | year = 1902 | title = Die Meer-Krocodilier (Thalattosuchia) des oberen Jura unter specieller Berücksichtigung von Dacosaurus und Geosaurus | journal = Palaeontographica | volume = 49 | pages = 1–72 }} Like ichthyosaurs and plesiosaurs, metriorhynchids developed smooth, scaleless skin.{{Cite journal|last1=Spindler|first1=Frederik|last2=Lauer|first2=René|last3=Tischlinger|first3=Helmut|last4=Mäuser|first4=Matthias|date=2021-07-05|title=The integument of pelagic crocodylomorphs (Thalattosuchia: Metriorhynchidae)|url=https://palaeo-electronica.org/content/2021/3399-metriorhynchid-skin|journal=Palaeontologia Electronica|language=English|volume=24|issue=2|pages=1–41|doi=10.26879/1099|issn=1094-8074|doi-access=free}}
Metriorhynchids were the only group of archosaurs to become fully adapted to the marine realm, becoming pelagic in lifestyle.Steel R. 1973. Crocodylia. Handbuch der Paläoherpetologie, Teil 16. Stuttgart: Gustav Fischer Verlag,116 pp. With tail flukes, reduced limb musculature, and long bones histologically comparable to other obligately aquatic animals, they were almost certainly incapable of terrestrial locomotion; combined with an unusually tall hip opening, as also seen in other obligately aquatic reptiles including the viviparous Keichousaurus, these characters suggest that metriorhynchids gave live birth.{{cite journal | first1 = Y. | last1 = Herrera | first2 = M.S. | last2 = Fernandez | first3 = S.G. | last3 = Lamas | first4 = L. | last4 = Campos | first5 = M. | last5 = Talevi | first6 = Z. | last6 = Gasparini | title = Morphology of the sacral region and reproductive strategies of Metriorhynchidae: a counter-inductive approach | doi = 10.1017/S1755691016000165 | journal = Earth and Environmental Science Transactions of the Royal Society of Edinburgh | volume = 106 | issue = 4 | pages = 247–255 | date = 2017| doi-access = free | hdl = 11336/66599 | hdl-access = free }} A fossil of a pregnant Dakosaurus female recovered from the Late Jurassic plattenkalk, Bavaria, preserves the complete skeleton of a neonate with small, paddle-like forelimbs unsuited for walking on land, similar to those of adults, further supporting live birth in metriorhynchids.{{cite book|year=2019|author=Spindler, Frederik|url=https://www.palaeontologie.geowissenschaften.uni-muenchen.de/pdfs/palges2019_abstracts.pdf#page=141|title=Live Birth in a Jurassic Marine Crocodile [abstract]. In: Abstracts of the 90th Annual Meeting of the Paläontologische Gesellschaft|publisher= SNSB - BSPG, München|page=141|isbn=978-3-946705-07-9|archive-url=https://web.archive.org/web/20230517045802/https://www.palaeontologie.geowissenschaften.uni-muenchen.de/pdfs/palges2019_abstracts.pdf#page=141|archive-date=2023-05-17|url-status=live}}{{cite book|year=2019|author=Spindler, Frederik|url=https://www.palaeontologie.geowissenschaften.uni-muenchen.de/pdfs/palges2019_abstracts.pdf#page=10|title=When Bavaria was the Ancient Caribbean – Plattenkalk Fossil Treasures from Painten [abstract]. In: Abstracts of the 90th Annual Meeting of the Paläontologische Gesellschaft|publisher= SNSB - BSPG, München|page=10|isbn=978-3-946705-07-9|archive-url=https://web.archive.org/web/20230517045802/https://www.palaeontologie.geowissenschaften.uni-muenchen.de/pdfs/palges2019_abstracts.pdf#page=10|archive-date=2023-05-17|url-status=live}} Recent research posits that despite their successful adaptation to a pelagic lifestyle, basal metriorhynchids were uniquely disadvantaged among aquatic tetrapods in evolving into sustained swimmers due to little to no posterodorsal retraction of the external nares (unlike other reptilian groups such as mesosaurs, phytosaurs, thalattosaurians, saurosphargids, ichthyosauriforms, sauropterygians, pleurosaurids or mosasauroids, as well as mammalian cetaceans or sirenians).{{cite journal|author1= Young, M.T.|author2= Sachs, S.|author3= Abel, P.|author4= Foffa, D.|author5= Herrera, Y.|author6= Kitson, J.J.N.|year= 2020|title= Convergent evolution and possible constraint in the posterodorsal retraction of the external nares in pelagic crocodylomorphs |journal= Zoological Journal of the Linnean Society |volume= 189|issue= 2|pages= 494–520|doi= 10.1093/zoolinnean/zlaa021|doi-access= free|hdl= 11336/137182|hdl-access= free}} The family has a wide geographic distribution, with material found in Argentina, Chile, Cuba, England, France, Germany, Italy, Mexico, Poland, Russia, Switzerland and Czech Republic.{{cite journal|author=Daniel Madzia, Sven Sachs, Mark T. Young, Alexander Lukeneder, Petr Skupien|year=2021|url=https://www.app.pan.pl/archive/published/app66/app008012020.pdf|title=Evidence of two lineages of metriorhynchid crocodylomorphs in the Lower Cretaceous of the Czech Republic|journal=Acta Palaeontologica Polonica|volume=66|issue=2|page=1-11|doi=10.4202/app.00801.2020|archive-url=https://web.archive.org/web/20210521113300/https://www.app.pan.pl/archive/published/app66/app008012020.pdf|archive-date=2021-05-21|url-status=dead}}
Classification
Phylogenetic analyses published during the 2000s cast doubt on the idea that many traditional metriorhynchid genera formed natural groups (i.e., include all descendants of a common ancestor). The traditional species of Geosaurus, Dakosaurus and Cricosaurus were found to represent unnatural groups, and the species traditionally classified in these genera were reshuffled in a study published in November 2009 by Mark T. Young and Marco Brandalise de Andrade. The monophyly of Metriorhynchus{{cite journal | author = Young MT | year = 2007 | title = The evolution and interrelationships of Metriorhynchidae (Crocodyliformes, Thalattosuchia) | doi = 10.1080/02724634.2007.10010458| journal = Journal of Vertebrate Paleontology | volume = 27 | issue = 3| page = 170A }}{{cite journal |vauthors=Wilkinson LE, Young MT, Benton MJ | year = 2008 | title = A new metriorhynchid crocodilian (Mesoeucrocodylia: Thalattosuchia) from the Kimmeridgian (Upper Jurassic) of Wiltshire, UK. | journal = Palaeontology | volume = 51 | issue = 6| pages = 1307–1333 | doi=10.1111/j.1475-4983.2008.00818.x| doi-access = free | bibcode = 2008Palgy..51.1307W }}{{cite journal |vauthors=Gasparini Z, Pol D, Spalletti LA | year = 2006 | title = An unusual marine crocodyliform from the Jurassic-Cretaceous boundary of Patagonia | journal = Science | volume = 311 | issue = 5757| pages = 70–73 | doi=10.1126/science.1120803| pmid = 16282526 | bibcode = 2006Sci...311...70G | s2cid = 10312971 | doi-access = free | hdl = 11336/73480 | hdl-access = free }} and Teleidosaurus{{cite journal | author = Mueller-Töwe IJ | year = 2005 | title = Phylogenetic relationships of the Thalattosuchia | journal = Zitteliana | volume = A45 | pages = 211–213 }} is also unsupported, and the species of these genera are pending reclassification.
The classification presented by Young and Andrade in 2009 was approved in later studies of the Metriorhynchidae.{{cite journal|author1=Andrea Cau |author2=Federico Fanti |year=2011 |title=The oldest known metriorhynchid crocodylian from the Middle Jurassic of North-eastern Italy: Neptunidraco ammoniticus gen. et sp. nov. |journal=Gondwana Research |volume=19 |issue=2 |pages=550–565 |doi=10.1016/j.gr.2010.07.007|bibcode=2011GondR..19..550C }}{{cite journal|author1=Mark T. Young |author2=Mark A. Bell |author3=Stephen L. Brusatte |year=2011 |title=Craniofacial form and function in Metriorhynchidae (Crocodylomorpha: Thalattosuchia): modelling phenotypic evolution with maximum-likelihood methods |journal=Biology Letters |volume=7 |issue=6 |pages=913–916 |doi=10.1098/rsbl.2011.0357 |pmid=21543396 |pmc=3210659}} Metriorhynchidae is a node-based taxon defined in the PhyloCode by Mark T. Young and colleagues in 2024 as "the smallest clade within Metriorhynchoidea containing Thalattosuchus superciliosus, Gracilineustes leedsi, Metriorhynchus brevirostris, Rhacheosaurus gracilis, and Geosaurus giganteus" {{cite journal |doi=10.1093/zoolinnean/zlad165 |title=The history, systematics, and nomenclature of Thalattosuchia (Archosauria: Crocodylomorpha) |date=2024 |last1=Young |first1=Mark T. |last2=Wilberg |first2=Eric W. |last3=Johnson |first3=Michela M. |last4=Herrera |first4=Yanina |last5=De Andrade |first5=Marco Brandalise |last6=Brignon |first6=Arnaud |last7=Sachs |first7=Sven |last8=Abel |first8=Pascal |last9=Foffa |first9=Davide |last10=Fernández |first10=Marta S. |last11=Vignaud |first11=Patrick |last12=Cowgill |first12=Thomas |last13=Brusatte |first13=Stephen L. |journal=Zoological Journal of the Linnean Society |volume=200 |issue=2 |pages=547–617 |doi-access=free }} The cladogram below follows the topology from the 2020 analyses by Young et al. and reduced to genera only.{{cite journal|author=Young, M.T., Brignon, A., Sachs, S., Hornung J.J., Foffa, D., Kitson, J.J.N., Johnson, M.M., Steel, L.|date=November 2020|url=|title=Cutting the Gordian knot: a historical and taxonomic revision of the Jurassic crocodylomorph Metriorhynchus|journal=Zoological Journal of the Linnean Society|volume=192|issue=2|pages=510–553 |doi=10.1093/zoolinnean/zlaa092}}
{{clade| style=font-size:100%;line-height:85%
|label1=Metriorhynchidae
|1={{clade
|label1=Metriorhynchinae
|1={{clade
|2={{clade
|2={{clade
|2={{clade
|label2=Rhacheosaurini
|2={{clade
|1=Cricosaurus }} }} }} }} }}
|label2=Geosaurinae
|2={{clade
|1=Neptunidraco
|2={{clade
|label1=Geosaurini
|1={{clade
|1={{clade
|2={{clade
|1=Torvoneustes
|2='E-clade'
|3=Purranisaurus }} }}
|2={{clade
|1={{clade
|1=Ieldraan
|2=Geosaurus }}
|2={{clade
|1=Dakosaurus
|2={{clade
|1=Plesiosuchus
|2=Suchodus }} }} }} }} }} }} }} }}
=List of genera=
The type genus of the family Metriorhynchidae is Metriorhynchus from the Middle to Late Jurassic. Other genera included within this family are Cricosaurus, Geosaurus, and Dakosaurus. Though once considered a metriorhynchid, Teleidosaurus has since been found to be slightly more distantly related to these animals within the superfamily Metriorhynchoidea.{{cite journal|author=Stéphane Hua|date=May 2020|title=A new specimen of Teleidosaurus calvadosii (Eudes-Deslongchamps, 1866) (Crocodylia, Thalattosuchia) from the Middle Jurassic of France|journal=Annales de Paléontologie|volume=106|issue=4|doi=10.1016/j.annpal.2020.102423|bibcode=2020AnPal.10602423H }}
Within this family, the genus Neustosaurus and Enaliosuchus are considered nomen dubium ("doubtful name").{{cite journal | author = Buffetaut E | year = 1982 | title = Radiation évolutive, paléoécologie et biogéographie des Crocodiliens mésosuchienes | journal = Mémoires de la Société Géologique de France | volume = 142 | pages = 1–88 }}
The genus Capelliniosuchus was once thought to be a metriorhynchid similar to Dakosaurus.{{cite journal | author = Simonelli V | year = 1896 | title = Intoro agli avanzi di coccodrilliano scoperti a San Valentino (provincial di Reggio Emilia) nel 1886 | journal = Atli della Reale Accademia dei Lincei, Series Qunita Rendiconti | volume = 5 | issue = 2| pages = 11–18 }} However, it was later found to be a mosasaur.{{Cite journal |last1=Fanti |first1=Federico |last2=Cau |first2=Andrea |last3=Negri |first3=Alessandra |date=2014-05-01 |title=A giant mosasaur (Reptilia, Squamata) with an unusually twisted dentition from the Argille Scagliose Complex (late Campanian) of Northern Italy |url=https://www.sciencedirect.com/science/article/pii/S0195667114000068 |journal=Cretaceous Research |language=en |volume=49 |pages=91–104 |doi=10.1016/j.cretres.2014.01.003 |bibcode=2014CrRes..49...91F |issn=0195-6671}}
Subclades
Summary of the phylogenetic definitions of metriorhynchid subclades shown in the classification section. These are based on Young and colleagues 2024.
class="wikitable sortable" align="center" width="100%"
! Name ! Named by ! Definition |
Dakosaurina
| The largest clade within Metriorhynchidae containing Dakosaurus maximus, but not Metriorhynchus brevirostris, Geosaurus giganteus, Plesiosuchus manselii, and Torvoneustes carpenteri. |
Geosaurina
| Bonaparte, 1845 | The largest clade within Metriorhynchidae containing Geosaurus giganteus, but not Metriorhynchus brevirostris, Plesiosuchus manselii, Torvoneustes carpenteri, and Dakosaurus maximus. |
Geosaurinae
| Bonaparte, 1845 | The largest clade within Metriorhynchidae containing Geosaurus giganteus, but not Rhacheosaurus gracilis, Metriorhynchus brevirostris, and Gracilineustes leedsi. |
Geosaurini
| Bonaparte, 1845 | The smallest clade within Metriorhynchidae containing Tyrannoneustes lythrodectikos, Geosaurus giganteus, Torvoneustes carpenteri, and Dakosaurus maximus. |
Metriorhynchidae
| Fitzinger, 1843 | The smallest clade within Metriorhynchoidea containing Thalattosuchus superciliosus, Gracilineustes leedsi, Metriorhynchus brevirostris, Rhacheosaurus gracilis, and Geosaurus giganteus. |
Metriorhynchinae
| Lydekker, 1888 | The smallest clade within Metriorhynchidae containing Rhacheosaurus gracilis, Metriorhynchus brevirostris, and Gracilineustes leedsi. |
Plesiosuchina
| Young et al.,2014 | The largest clade within Metriorhynchidae containing Plesiosuchus manselii, but not Metriorhynchus brevirostris, Geosaurus giganteus, Torvoneustes carpenteri, and Dakosaurus maximus. |
Rhacheosaurini
| Young et al., 2011 | The largest clade within Metriorhynchidae containing Rhacheosaurus gracilis, but not Metriorhynchus brevirostris and Gracilineustes leedsi. |
See also
{{Portal|Paleontology}}
References
{{Reflist|2}}
External links
- {{cite web|url=http://palaeos.com/vertebrates/crocodilia/crocodyliformes.html#Metriorhynchidae|title=Crocodilia: Crocodyliformes (Gobiosuchids, Teleosaurs & Metriorhynchids)|website=Palaeos|archive-url=https://web.archive.org/web/20230217000801/http://palaeos.com/vertebrates/crocodilia/crocodyliformes.html#Metriorhynchidae|archive-date=2023-02-17|url-status=live}}
{{Thalattosuchia}}
{{Taxonbar|from=Q134271}}
Category:Middle Jurassic crocodylomorphs
Category:Early Cretaceous crocodylomorphs
Category:Pseudosuchian families
Category:Prehistoric marine crocodylomorphs
Category:Middle Jurassic first appearances