{{Short description|Extinct family of temnospondyls}} {{Use dmy dates|date=March 2025}} {{Automatic taxobox | name = Metoposaurids | fossil_range = | image = Metoposaurus_diagnosticus_kraselovi_1DB.jpg | image_caption = ''[[Metoposaurus]]'' | taxon = Metoposauridae | authority = [[David Meredith Seares Watson|Watson]], 1919 | subdivision_ranks = Genera | subdivision = *{{extinct}}''[[Anaschisma]]'' *{{extinct}}''[[Apachesaurus]]'' *{{extinct}}''[[Arganasaurus]]'' *{{extinct}}''[[Buettnererpeton]]'' *{{extinct}}''[[Dutuitosaurus]]'' *{{extinct}}''[[Metoposaurus]]'' *{{extinct}}''[[Panthasaurus]]'' }}
'''Metoposauridae''' is an extinct [[Family (taxonomy)|family]] of [[trematosauria]]n [[temnospondyl]]s. The family is known from the [[Late Triassic]] period. Most members are large, approximately {{convert|1.5|m|ft}} long and could reach 3 m long.<ref name=":0">Brusatte, S. L., Butler R. J., Mateus O., & Steyer S. J. (2015). A new species of Metoposaurus from the Late Triassic of Portugal and comments on the systematics and biogeography of metoposaurid temnospondyls. Journal of Vertebrate Paleontology. e912988., 2015:</ref> Metoposaurids can be distinguished from most other stereospondyls by the position of their eyes, placed far forward on the snout (the type genus, ''[[Metoposaurus]]'', means 'front lizard').
== Geographic distribution == Metoposaurids had a wide distribution across Pangea, being known from across the continental United States and Nova Scotia in North America;<ref name=":1">{{Cite journal |last1=Gee |first1=Bryan M. |last2=Kufner |first2=Aaron M. |date=2022-10-12 |title=Revision of the Late Triassic metoposaurid "Metoposaurus" bakeri (Amphibia: Temnospondyli) from Texas, USA and a phylogenetic analysis of the Metoposauridae |url=https://peerj.com/articles/14065 |journal=PeerJ |language=en |volume=10 |article-number=e14065 |doi=10.7717/peerj.14065 |doi-access=free |issn=2167-8359}}</ref><ref name=":2">{{Cite journal |last1=Kufner |first1=Aaron M. |last2=Deckman |first2=Max E. |last3=Miller |first3=Hannah R. |last4=So |first4=Calvin |last5=Price |first5=Brandon R. |last6=Lovelace |first6=David M. |title=A new metoposaurid (Temnospondyli) bonebed from the lower Popo Agie Formation (Carnian, Triassic) and an assessment of skeletal sorting |journal=PLOS ONE |date=2025 |volume=20 |issue=4 |article-number=e0317325 |doi=10.1371/journal.pone.0317325 |doi-access=free |pmid=40173156 |pmc=11964259 |bibcode=2025PLoSO..2017325K |biorxiv=10.1101/2024.12.28.630624 }}</ref><ref>{{Cite journal |last1=Sues |first1=Hans-Dieter |last2=Olsen |first2=Paul E. |last3=Fedak |first3=Tim J. |last4=Schoch |first4=Rainer R. |date=2021-07-04 |title=Diverse assemblage of Middle Triassic continental tetrapods from the Newark Supergroup of Nova Scotia (Canada) |journal=Journal of Vertebrate Paleontology |volume=41 |issue=4 |article-number=e2023168 |doi=10.1080/02724634.2021.2023168 |bibcode=2021JVPal..41E3168S |issn=0272-4634}}</ref><ref name=":3">{{Cite journal |last=Hunt |first=Adrian P. |date=1993 |title=Revision of the Metoposauridae (Amphibia: Temnospobdyli) and description of a new genus from Western North America |journal=Museum of Northern Arizona Bulletin |volume=59 |pages=67–97}}</ref><ref name=":6">{{Cite journal |last1=Long |first1=Robert A. |last2=Murry |first2=Phillip A. |date=1995 |title=Late Triassic (Carnian and Norian) tetrapods from the Southwestern United States |journal=New Mexico Museum of Natural History and Science Bulletin |volume=4 |pages=1–254}}</ref> France,<ref name=":4">{{Cite book |last1=Schoch |first1=Rainer R. |title=Handbook of Paleoherpetology: Part 3B (Stereospondyli) |last2=Milner |first2=Andrew R. |last3=Kuhn |first3=Oskar |last4=Wellnhofer |first4=Peter |date=2000 |publisher=Verl. Dr. Friedrich Pfeil |isbn=978-3-931516-77-2 |location=München}}</ref> Germany,<ref>{{Cite journal |last1=Milner |first1=Andrew R. |last2=Schoch |first2=Rainer R. |date=2004-07-09 |title=The latest metoposaurid amphibians from Europe |journal=Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen |volume=232 |issue=2–3 |pages=231–252 |doi=10.1127/njgpa/232/2004/231 |bibcode=2004NJGPA.232..231M |issn=0077-7749}}</ref><ref name=":7">{{Cite journal |last1=Schoch |first1=Rainer R. |last2=Moreno |first2=Raphael |date=2024-05-31 |title=Synopsis on the temnospondyls from the German Triassic |journal=Palaeodiversity |volume=17 |issue=1 |doi=10.18476/pale.v17.a2 |issn=1867-6294|doi-access=free }}</ref><ref>{{Cite journal |last1=Moreno |first1=Raphael |last2=Chakravorti |first2=Sanjukta |last3=Cooper |first3=Samuel L. A. |last4=Schoch |first4=Rainer R. |date=2024-12-30 |title=Unexpected temnospondyl diversity in the early Carnian Grabfeld Formation (Germany) and the palaeogeography of metoposaurids |journal=Fossil Record |volume=27 |issue=3 |pages=381–400 |doi=10.3897/fr.27.121996 |doi-access=free |bibcode=2024FossR..27..381M |issn=2193-0074}}</ref> Italy,<ref name=":4" /> Poland,<ref name=":8">{{Cite journal |last=Sulej |first=Tomasz |date=2002 |title=Species discrimination of the Late Triassic temnospondyl amphibian Metoposaurus diagnosticus |journal=Acta Palaeontologica Polonica |volume=47 |pages=535–546}}</ref><ref name=":9">{{Cite journal |last=Sulej |first=Tomasz |date=2007 |title=Osteology, variability, and evolution of Metoposaurus, a temnospondyl from the Late Triassic of Poland |journal=Palaeontologia Polonica |volume=64 |pages=29–139}}</ref> and Portugal in western Europe;<ref>{{Cite journal |last1=Witzmann |first1=Florian |last2=Gassner |first2=Thomas |date=March 2008 |title=Metoposaurid and mastodonsaurid stereospondyls from the Triassic – Jurassic boundary of Portugal |journal=Alcheringa: An Australasian Journal of Palaeontology |volume=32 |issue=1 |pages=37–51 |doi=10.1080/03115510701757316 |bibcode=2008Alch...32...37W |issn=0311-5518}}</ref><ref name=":0" /> India;<ref>{{Cite journal |last1=Rakshit |first1=Nibedita |last2=Ray |first2=Sanghamitra |date=2020-06-16 |title=Mortality dynamics and fossilisation pathways of a new metoposaurid-dominated multitaxic bonebed from India: a window into the Late Triassic vertebrate palaeoecosystem |journal=Historical Biology |volume=33 |issue=10 |pages=2193–2215 |doi=10.1080/08912963.2020.1777550 |issn=0891-2963}}</ref><ref name=":10">{{Cite journal |last=Roychowdhury |first=T. |date=1965-11-18 |title=A new metoposaurid amphibian from the upper Triassic Maleri formation of Central India |journal=Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences |volume=250 |issue=761 |pages=1–52 |doi=10.1098/rstb.1965.0019 |bibcode=1965RSPTB.250....1C |issn=2054-0280}}</ref><ref>{{Cite journal |last=Sengupta |first=Dhurjati Prasad |date=2002-04-28 |title=Indian metoposaurid amphibians revised |journal=Paleontological Research |volume=6 |issue=1 |pages=41–65 |article-number=41 |doi=10.2517/prpsj.6.41 |issn=1342-8144|doi-access=free |bibcode=2002PalRe...6...41S }}</ref><ref>{{Cite journal |last1=Chakravorti |first1=Sanjukta |last2=Sengupta |first2=Dhurjati Prasad |date=2018-10-02 |title=Taxonomy, morphometry and morphospace of cranial bones of Panthasaurus gen. nov. maleriensis from the Late Triassic of India |journal=Journal of Iberian Geology |volume=45 |issue=2 |pages=317–340 |doi=10.1007/s41513-018-0083-1 |issn=1698-6180}}</ref> Morocco;<ref name=":5">{{Cite journal |last=Dutuit |first=Jean-Michel |date=1976 |title=Introduction à l'étude paléontologique du Trias continental marocain: description des premiers Stégocéphales recueillis dans le couloir d'Argana (Atlas occidental) |journal=Mémoires du Muséum National d'Histoire Naturelle. Série C, Sciences de la Terre |volume=36 |pages=1–253}}</ref><ref>{{Cite journal |last1=Buffa |first1=Valentin |last2=Jalil |first2=Nour-Eddine |last3=Steyer |first3=J.-Sebastien |date=2019-06-03 |title=Redescription of ''Arganasaurus'' (''Metoposaurus) azerouali'' (Dutuit) comb. nov. from the Upper Triassic of the Argana Basin (Morocco), and the first phylogenetic analysis of the Metoposauridae (Amphibia, Temnospondyli) |journal=Papers in Palaeontology |volume=5 |issue=4 |pages=699–717 |doi=10.1002/spp2.1259 |bibcode=2019PPal....5..699B |issn=2056-2799 |url=https://hal.sorbonne-universite.fr/hal-02967815 }}</ref> and Madagascar.<ref>{{Cite journal |last1=Fortuny |first1=Josep |last2=Arbez |first2=Thomas |last3=Mujal |first3=Eudald |last4=Steyer |first4=J. Sébastien |date=2019-01-02 |title=Reappraisal of '''Metoposaurus hoffmani''' Dutuit, 1978, and description of new temnospondyl specimens from the Middle–Late Triassic of Madagascar (Morondava Basin) |journal=Journal of Vertebrate Paleontology |volume=39 |issue=1 |article-number=e1576701 |doi=10.1080/02724634.2019.1576701 |bibcode=2019JVPal..39E6701F |issn=0272-4634}}</ref> Material has also been reported from Zimbabwe but was not collected.<ref>{{Cite journal |last1=Barrett |first1=Paul M. |last2=Sciscio |first2=Lara |last3=Viglietti |first3=Pia A. |last4=Broderick |first4=Timothy J. |last5=Suarez |first5=Celina A. |last6=Sharman |first6=Glenn R. |last7=Jones |first7=Andrew S. |last8=Munyikwa |first8=Darlington |last9=Edwards |first9=Steve F. |last10=Chapelle |first10=Kimberley E.J. |last11=Dollman |first11=Kathleen N. |last12=Zondo |first12=Michel |last13=Choiniere |first13=Jonah N. |date=May 2020 |title=The age of the Tashinga Formation (Karoo Supergroup) in the Mid-Zambezi Basin, Zimbabwe and the first phytosaur from mainland sub-Saharan Africa |journal=Gondwana Research |volume=81 |pages=445–460 |doi=10.1016/j.gr.2019.12.008 |bibcode=2020GondR..81..445B |issn=1342-937X |url=https://birmingham.elsevierpure.com/en/publications/bc9fac85-4d72-4df0-8c4f-62b9a9fd839b }}</ref><ref>{{Cite journal |last1=Sciscio |first1=Lara |last2=Viglietti |first2=Pia A. |last3=Barrett |first3=Paul M. |last4=Broderick |first4=Timothy J. |last5=Munyikwa |first5=Darlington |last6=Chapelle |first6=Kimberley E.J. |last7=Dollman |first7=Kathleen N. |last8=Edwards |first8=Steve F. |last9=Zondo |first9=Michel |last10=Choiniere |first10=Jonah N. |date=2020-10-26 |title=Sedimentology and palaeontology of the Upper Karoo Group in the Mid-Zambezi Basin, Zimbabwe: new localities and their implications for interbasinal correlation |journal=Geological Magazine |volume=158 |issue=6 |pages=1035–1058 |doi=10.1017/s0016756820001089 |issn=0016-7568}}</ref> At least some historic reports of metoposaurid material are likely undiagnostic below Stereospondyli<ref name=":3" /><ref name=":4" /> or are referable to other clades.<ref>{{Cite journal |last1=Sues |first1=Hans-Dieter |last2=Schoch |first2=Rainer R. |date=2013-09-01 |title=Anatomy and phylogenetic relationships of Calamops paludosus (Temnospondyli, Stereospondyli) from the Triassic of the Newark Basin, Pennsylvania |journal=Journal of Vertebrate Paleontology |volume=33 |issue=5 |pages=1061–1070 |doi=10.1080/02724634.2013.759120 |bibcode=2013JVPal..33.1061S |issn=0272-4634}}</ref><ref>{{Cite journal |last1=Lucas |first1=Spencer G. |last2=Hunt |first2=Adrian P. |date=1993 |title=A review of Triassic labyrinthodont amphibians from China |journal=Geobios |volume=26 |issue=1 |pages=121–128 |doi=10.1016/s0016-6995(93)80012-g |bibcode=1993Geobi..26..121L |issn=0016-6995}}</ref>
== History of study == Metoposaurids were one of the first clades of temnospondyls to be named on the basis of ''Metoposaurus diagnosticus'' from Germany, named in 1842 by German paleontologist [[Christian Erich Hermann von Meyer|Hermann von Meyer]]. Several additional species of questionable validity were named in the early 20th century from Italy (''Metoposaurus santecrucis'') and Germany (''Metoposaurus stuttgartensis'', ''Metoposaurus heimi''). Although metoposaurids are common in Late Triassic deposits of Germany,<ref name=":7" /> no bonebeds have been discovered, and the most extensive amount of material comes from the Krasiejow bonebed in Poland.<ref name=":9" /> Most recently, a large body of material was recovered from Portugal.<ref name=":0" /> Most collecting in North America was conducted in the 20th and 21st centuries, although '''Dictyocephalus elegans'',' usually regarded as an indeterminate metoposaurid, was described from the Late Triassic of North Carolina by [[Joseph Leidy]] in 1856. The most extensive remains are known from Arizona, New Mexico, Texas, and Wyoming.<ref name=":6" /> Collecting efforts in the mid-20th century yielded extensive remains from Morocco<ref name=":5" /> and India<ref name=":10" /> and more fragmentary remains from Madagascar.<ref>{{Cite journal |last=Dutuit |first=Jean-Michel |date=1978 |title=Description de quelques fragments osseux provenant de la région de Folakara (Trias supérieur malgache) |journal=Bulletin du Muséum national d'Histoire naturelle, Paris, 3e sér., 516, Sciences de la Terre |volume=69 |pages=79–89}}</ref>
The majority of work on metoposaurids has been descriptive or taxonomic in nature, with a very large number of named taxa, the majority of which have now been synonymized with other taxa or determined to not be diagnostic at the species level. The taxonomy of the clade has undergone significant revision as a result.<ref>{{Cite journal |last1=Colbert |first1=Edwin H. |last2=Imbrie |first2=John H. |date=1956 |title=Triassic metoposaurid amphibians |url=http://hdl.handle.net/2246/431 |journal=Bulletin of the American Museum of Natural History |volume=110 |pages=403–452 |hdl=2246/431 }}</ref><ref name=":3" /><ref name=":8" /> The commonality of metoposaurid material in some geographic regions and the quality of preservation of many specimens has also permitted additional study that is not as feasible for other temnospondyl clades. The Krasiejow bonebed has been extensively utilized for paleohistological analyses to infer ecological attributes of the local population, with nearly every skeletal element examined.<ref>{{Cite journal |last1=Konietzko-Meier |first1=Dorota |last2=Sander |first2=P. Martin |date=September 2013 |title=Long bone histology of''Metoposaurus diagnosticus''(Temnospondyli) from the Late Triassic of Krasiejów (Poland) and its paleobiological implications |journal=Journal of Vertebrate Paleontology |volume=33 |issue=5 |pages=1003–1018 |doi=10.1080/02724634.2013.765886 |bibcode=2013JVPal..33.1003K |issn=0272-4634}}</ref><ref>{{Cite journal |last1=Konietzko-Meier |first1=Dorota |last2=Klein |first2=Nicole |date=January 2013 |title=Unique growth pattern of Metoposaurus diagnosticus krasiejowensis (Amphibia, Temnospondyli) from the Upper Triassic of Krasiejów, Poland |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=370 |pages=145–157 |doi=10.1016/j.palaeo.2012.12.003 |bibcode=2013PPP...370..145K |issn=0031-0182}}</ref><ref>{{Cite journal |last1=Gruntmejer |first1=Kamil |last2=Konietzko-Meier |first2=Dorota |last3=Bodzioch |first3=Adam |last4=Fortuny |first4=Josep |date=2018-07-03 |title=Morphology and preliminary biomechanical interpretation of mandibular sutures in Metoposaurus krasiejowensis (Temnospondyli, Stereospondyli) from the Upper Triassic of Poland |journal=Journal of Iberian Geology |volume=45 |issue=2 |pages=301–316 |doi=10.1007/s41513-018-0072-4 |issn=1698-6180}}</ref><ref>{{Cite journal |last1=Teschner |first1=Elżbieta M. |last2=Sander |first2=P. Martin |last3=Konietzko-Meier |first3=Dorota |date=2017-10-23 |title=Variability of growth pattern observed in Metoposaurus krasiejowensis humeri and its biological meaning |journal=Journal of Iberian Geology |volume=44 |issue=1 |pages=99–111 |doi=10.1007/s41513-017-0038-y |issn=1698-6180|doi-access=free }}</ref><ref>{{Cite journal |last1=Gruntmejer |first1=Kamil |last2=Bodzioch |first2=Adam |last3=Konietzko-Meier |first3=Dorota |date=2021-09-30 |title=Mandible histology in Metoposaurus krasiejowensis (Temnospondyli, Stereospondyli) from the Upper Triassic of Poland |journal=PeerJ |language=en |volume=9 |article-number=e12218 |doi=10.7717/peerj.12218 |doi-access=free |issn=2167-8359 |pmc=8487625 |pmid=34703667}}</ref><ref>{{Cite journal |last1=Kalita |first1=Sudipta |last2=Teschner |first2=Elżbieta M. |last3=Sander |first3=P. Martin |last4=Konietzko-Meier |first4=Dorota |date=2022-09-27 |title=To be or not to be heavier: The role of dermal bones in the buoyancy of the Late Triassic temnospondyl amphibian ''Metoposaurus krasiejowensis'' |journal=Journal of Anatomy |volume=241 |issue=6 |pages=1459–1476 |doi=10.1111/joa.13755 |pmid=36165276 |issn=0021-8782|pmc=9644956 }}</ref><ref>{{Cite journal |last1=Teschner |first1=Elżbieta |last2=Garbay |first2=Laurent |last3=Janecki |first3=Piotr |last4=Konietzko-Meier |first4=Dorota |date=2023 |title=Palaeohistology helps reveal taxonomic variability in exceptionally large temnospondyl humeri from the Late Triassic Krasiejów deposit (SW Poland). |journal=Acta Palaeontologica Polonica |volume=68 |doi=10.4202/app.01027.2022 |issn=0567-7920|doi-access=free }}</ref><ref>{{Cite journal |last1=Konietzko-Meier |first1=Dorota |last2=Prino |first2=Andrea |last3=Teschner |first3=Elżbieta M. |date=2025-06-03 |title=Hips do not lie… histology of the pelvic girdle elements of Metoposaurus from the Late Triassic of Poland |journal=Fossil Record |volume=28 |issue=1 |pages=165–178 |doi=10.3897/fr.28.e153929 |doi-access=free |bibcode=2025FossR..28..165K |issn=2193-0074}}</ref><ref>{{Cite journal |last1=Kalita |first1=Sudipta |last2=Teschner |first2=Elżbieta M. |last3=Konietzko-Meier |first3=Dorota |date=2025 |title=Illuminating the dark mess of fibers: Application of circular cross polarized light in unravelling the bone tissue structure of the dermal pectoral girdle of Metoposaurus krasiejowensis |journal=Journal of Anatomy |language=en |volume=247 |issue=3–4 |pages=442–465 |doi=10.1111/joa.14197 |issn=1469-7580 |pmc=12397061 |pmid=39823289}}</ref>
==Taphonomy== Several mass accumulations of dozens of individuals are known from the southwestern United States and Morocco.<ref name=":1" /><ref name=":2" /><ref>{{Cite journal |last1=Lucas |first1=Spencer G. |last2=Rinehart |first2=Larry F. |last3=Heckert |first3=Andrew B. |last4=Hunt |first4=Adrian P. |last5=Spielmann |first5=Justin A. |date=2016 |title=Rotten Hill: A Late Triassic bonebed in the Texas Panhandle |journal=New Mexico Museum of Natural History and Science Bulletin |volume=72 |pages=1–97}}</ref><ref name=":5" /> These have often been interpreted as the result of mass deaths from droughts, although only the deposits in Morocco and Wyoming are interpreted to have preserved the animals where they died;<ref name=":5" /><ref name=":2" /> in North America, it is thought that the deposits in Texas and New Mexico results from when the animals aggregated, died, and then were transported.<ref name="Letal10" /><ref name=":2" /> Most skeletons in the latter accumulations are disarticulated, suggesting they were transported by water to the deposition sites. These mass accumulations of metoposaurids are often dominated by one taxa, such as ''[[Anaschisma]]'', ''[[Buettnererpeton|Buettnerpeton]]'', or ''[[Dutuitosaurus]]''.<ref name=MPA87>{{cite journal |last=Murry |first=P.A. |year=1987 |title=Notes on the stratigraphy and paleontology of the Upper Triassic Dockum Group |journal=Journal of the Arizona-Nevada Academy of Science |volume=22 |issue=1 |pages=73–84}}</ref> The large gatherings of metoposaurids may have been breeding sites, and were probably common across floodplains in Late Triassic [[Pangaea]].<ref name=Letal10>{{cite journal |last=Lucas |first=S.G. |author2=Rinehart, L.F. |author3=Krainer, K. |author4=Spielmann, J.A. |author5= Heckert, A.B. |year=2010 |title=Taphonomy of the Lamy amphibian quarry: A Late Triassic bonebed in New Mexico, U.S.A. |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=298 |issue=4 |pages=388–398 |doi=10.1016/j.palaeo.2010.10.025|bibcode=2010PPP...298..388L |url=http://libres.uncg.edu/ir/asu/f/Heckert_Andrew_2010_Taphonomt_Lamy_Quarry_orig.pdf }}</ref>
==References== {{Reflist}}
{{Trematosauria|M.}} {{Taxonbar|from=Q6824275}}
[[Category:Triassic temnospondyls]] [[Category:Metoposauridae| ]] [[Category:Temnospondyl families]]