Macrospondylus
{{Short description|Extinct genus of reptiles}}
{{Speciesbox
| fossil_range = Toarcian {{Fossil range|183|180}}
| image = Macrospondylus bollensis Holzmaden.jpg
| image_caption = Macrospondylus bollensis, Holzmaden Germany
| genus= Macrospondylus
| display_parents = 3
| parent_authority = von Meyer, 1831
| species = bollensis
| authority = Jäger, 1828
| synonyms =
- Crocodilus bollensis (Jäger, 1828)
- Teleosaurus mandelsohi Bronn, 1841
- Steneosaurus bollensis (Cuvier, 1824)
}}
Macrospondylus is an extinct genus of machimosaurid teleosauroid crocodyliform from the Early Jurassic (Toarcian) of Europe. Fossils are known from the Posidonia Shale of Germany, the Whitby Mudstone of the United Kingdom, and the "schistes bitumineux" of Luxembourg.
Evolutionary relationships
File:Steneosaurus NT small.jpg
Macrospondylus has historically been synonymized with Steneosaurus.Steel R. 1973. Crocodylia. Handbuch der Paläoherpetologie, Teil 16. Stuttgart: Gustav Fischer Verlag,116 pp. A 2005 phylogenetic analysis of Thalattosuchia, however, did not support the monophyly of Steneosaurus, as the genera Machimosaurus and Teleosaurus both fell within Steneosaurus.{{cite journal |last=Mueller-Töwe |first=I. J. |year=2005 |title=Phylogenetic relationships of the Thalattosuchia |journal=Zitteliana |volume=A45 |pages=211–213 |url=http://epub.ub.uni-muenchen.de/11958/1/zitteliana_2005_45_09.pdf }} Reinforcing the paraphyly of Steneosaurus, Young et al. (2012), Ősi et al. (2018), and Wilberg et al. (2019) recovered Steneosaurus bollensis and other Steneosaurus species in disparate positions within Teleosauridae.Young, M. T.; Brusatte, S. L.; De Andrade, M. B.; Desojo, J. B.; Beatty, B. L.; Steel, L.; Fernández, M. S.; Sakamoto, M.; Ruiz-Omeñaca, J. I.; Schoch, R. R. (2012). Butler, Richard J, ed. "The Cranial Osteology and Feeding Ecology of the Metriorhynchid Crocodylomorph Genera Dakosaurus and Plesiosuchus from the Late Jurassic of Europe". PLoS ONE 7 (9): e44985. {{doi|10.1371/journal.pone.0044985|doi-access=free}}. {{PMC|3445579}}. {{PMID|23028723}}. editŐsi A, Young MT, Galácz A, Rabi M. 2018. A new large-bodied thalattosuchian crocodyliform from the Lower Jurassic (Toarcian) of Hungary, with further evidence of the mosaic acquisition of marine adaptations in Metriorhynchoidea. PeerJ 6:e4668 https://doi.org/10.7717/peerj.4668Eric W. Wilberg; Alan H. Turner; Christopher A. Brochu (2019). "Evolutionary structure and timing of major habitat shifts in Crocodylomorpha". Scientific Reports. 9 (1): Article number 514. doi:10.1038/s41598-018-36795-1. PMC 6346023. {{PMID|30679529}}.
In 2016, its length was estimated at {{cvt|5.5|m|ft}}, making it the largest known Early Jurassic crocodylomorph.{{Cite journal|url=http://palaeo-electronica.org/content/2016/1554-teleosaurid-size-estimation|doi=10.26879/648|title=Big-headed marine crocodyliforms and why we must be cautious when using extant species as body length proxies for long-extinct relatives|year=2016|last1=Young|first1=MT|last2=Rabi|first2=M.|last3=Bell|first3=MA|last4=Foffa|first4=D.|last5=Steel|first5=L.|last6=Sachs|first6=S.|last7=Peyer|first7=K.|journal=Palaeontologia Electronica|volume=19|issue=3|pages=1–14|doi-access=free}} In 2020, the genus was formally revived.{{cite journal |last1=Johnson |first1=Michela M. |last2=Young |first2=Mark T. |last3=Brusatte |first3=Stephen L. |title=The phylogenetics of Teleosauroidea (Crocodylomorpha, Thalattosuchia) and implications for their ecology and evolution |journal=PeerJ |date=2020 |volume=8 |pages=e9808 |doi=10.7717/peerj.9808|pmid=33083104 |pmc=7548081 |doi-access=free }}
Palaeobiology
M. bollensis exhibited a regular, stable growth rate until reaching adulthood. It was adapted primarily for life in aquatic environments but also retained some adaptations for terrestrial locomotion.{{Cite journal |last=Johnson |first=Michela M. |last2=Scheyer |first2=Torsten M. |last3=Canoville |first3=Aurore |last4=Maxwell |first4=Erin E. |date=28 September 2024 |title=Palaeohistology of Macrospondylus bollensis (Crocodylomorpha: Thalattosuchia: Teleosauroidea) from the Posidonienschiefer Formation (Toarcian) of Germany, with insights into life history and ecology |url=https://anatomypubs.onlinelibrary.wiley.com/doi/10.1002/ar.25577 |journal=The Anatomical Record |language=en |doi=10.1002/ar.25577 |issn=1932-8486 |access-date=9 December 2024 |via=Wiley Online Library|doi-access=free |pmc=11725703 }}
See also
{{Portal|Paleontology}}
References
{{Reflist}}
{{Thalattosuchia}}
{{Taxonbar|from=Q61963367}}
Category:Prehistoric pseudosuchian genera
Category:Prehistoric marine crocodylomorphs
Category:Early Jurassic crocodylomorphs
Category:Fossil taxa described in 1830