Thalattosuchia is a clade of mostly marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution.[3] They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not members of Crocodilia and records from Thailand and China suggest that some members lived in freshwater.[4] The clade contains two major subgroupings, the Teleosauroidea and Metriorhynchoidea. Teleosauroids are not greatly specialised for oceanic life, with back osteoderms similar to other crocodyliformes. Within Metriorhynchoidea, the Metriorhynchidae displayed extreme adaptions for life in the open ocean, including the transformation of limbs into flippers, the development of a tail fluke, and smooth, scaleless skin,[5] and probably gave live birth, seemingly uniquely among archosaurs.[6]

Thalattosuchians
Temporal range: Early Jurassic-Early Cretaceous Sinemurian–Aptian
Platysuchus,(Teleosauridae, Teleosauroidea)
Cricosaurus (Metriorhynchidae, Metriorhynchoidea)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Suborder: Thalattosuchia
Fraas, 1901[1]
Superfamilies

Taxonomy

edit

The term Thalattosuchia was coined by Fraas in 1901.[1] Various authors considered Thalattosuchia an infraorder or a suborder within "Mesosuchia". However, the term "Mesosuchia" is a paraphyletic group, and as such is no longer used. For consistency, the Thalattosuchia are here placed at suborder rank, although the order that contains it is unnamed. The exact phylogenetic position of Thalattosuchia is uncertain, with them either being interpreted as members of Neosuchia alongside other aquatic crocodylomorphs, or more basal members of Crocodylomorpha, with the similarities to neosuchians being as a result of convergent evolution.[7] Mark T. Young and colleagues in 2024 defined Thalattosuchia in the PhyloCode as "the largest clade within Crocodylomorpha containing Macrospondylus bollensis and Thalattosuchus superciliosus, but not Protosuchus richardsoni, Notosuchus terrestris, Peirosaurus tormini, Anteophthalmosuchus hooleyi, Deltasuchus motherali, Pholidosaurus schaumburgensis, Dyrosaurus phosphaticus, and Crocodylus niloticus (the Nile crocodile)".[2] 'The group contains basal taxa such as Turnersuchus and Plagiophthalmosuchus and the two main groups Metriorhynchoidea and Teleosauroidea.[8][9] Those two groups are united in the clade Neothalattosuchia, named and defined in the PhyloCode by Mark T. Young and colleagues in 2024 as "the smallest clade within Thalattosuchia containing Macrospondylus bollensis, Platysuchus multiscrobiculatus, Pelagosaurus typus, and Thalattosuchus superciliosus.[2]

Evolutionary history

edit

Indeterminate remains possibly belonging to thalattosuchians have been reported from the Early Jurassic (Sinemurian) of Chile and France. However, they cannot be assigned to the group with confidence as they lack diagnostic characters.[9] In 2023 a basal teleosauroid was reported from the earliest Jurassic (Hettangian-Sinemurian) of Morocco, representing one of the oldest known thalattosuchians.[10] Turnersuchus from the Pliensbachian of England appears to be basal to both Teleosauroidea and Metriorhynchoidea.[9] While abundant during the Jurassic, their fossil record during the Early Cretaceous is scarce, and generally confined to low latitudes. The latest records of the group date to the Aptian.[11][12] Some members of Teleosauridae have been discovered in non-marine deposits.[4]

Timeline of species

edit
CretaceousJurassicTriassicLate CretaceousEarly CretaceousLate JurassicMiddle JurassicEarly JurassicLate TriassicMiddle TriassicEarly TriassicMachimosaurus rexGeosaurus lapparentiCricosaurus schroederiNeustosaurus gigondarumEnaliosuchus macrospondylusCricosaurus puelchorumDakosaurus andiniensisCricosaurus lithographicusCricosaurus elegansCricosaurus bambergensisPurranisaurus potensIndosinosuchus potamosiamensisIndosinosuchus kalasinensisCricosaurus vignaudiCricosaurus araucanensisAeolodon priscusCricosaurus rauhutiGeosaurus grandisGeosaurus giganteusRhacheosaurus gracilisCricosaurus suevicusDakosaurus maximusMachimosaurus mosaeCricosaurus albersdoerferiPlesiosuchus manseliiMetriorhynchus brevirostrisMaledictosuchus nuyivijananMachimosaurus hugiiGracilineustes acutusBathysuchus megarhinusMachimosaurus buffetautiSericodon jugleriTorvoneustes carpenteriMachimosaurus nowackianusAggiosaurus nicaeensisSteneosaurus rostromajorMaledictosuchus riclaensisCharitomenosuchus leedsiProexochokefalos hebertiNeosteneosaurus edwardsiTyrannoneustes lythrodectikosIeldraan melkshanensisLemmysuchus obtusidensThalattosuchus superciliosusGracilineustes leedsiSuchodus durobrivensisNeptunidraco ammoniticusMycterosuchus nasutusYvridiosuchus boutilieriSeldsienean megistorhynchusProexochokefalos cf. bouchardiDeslongchampsina lartetiAndrianavoay baroniClovesuurdameredeor stephaniEoneustes gaudryiEoneustes bathonicusTeleidosaurus calvadosiiTeleosaurus cadomensisOpisuchus meieriZoneait nargorumMagyarosuchus fitosiPlatysuchus multiscrobiculatusPelagosaurus typusMystriosaurus laurillardiMacrospondylus bollensisPlagiophthalmosuchus gracilirostrisTurnersuchus hingleyaeCretaceousJurassicTriassicLate CretaceousEarly CretaceousLate JurassicMiddle JurassicEarly JurassicLate TriassicMiddle TriassicEarly Triassic

See also

edit

References

edit
  1. ^ a b Fraas E. 1901. Die Meerkrokodile (Thalattosuchia n. g.) eine neue Sauriergruppe der Juraformation. Jahreshefte des Vereins für vaterländische Naturkunde, Württemberg 57: 409-418.
  2. ^ a b c Young, Mark T.; Wilberg, Eric W.; Johnson, Michela M.; Herrera, Yanina; De Andrade, Marco Brandalise; Brignon, Arnaud; Sachs, Sven; Abel, Pascal; Foffa, Davide; Fernández, Marta S.; Vignaud, Patrick; Cowgill, Thomas; Brusatte, Stephen L. (2024). "The history, systematics, and nomenclature of Thalattosuchia (Archosauria: Crocodylomorpha)". Zoological Journal of the Linnean Society. 200 (2): 547–617. doi:10.1093/zoolinnean/zlad165.
  3. ^ Alfio A. Chiarenza; Davide Foffa; Mark T. Young; Gianni Insacco; Andrea Cau; Giorgio Carnevale; Rita Catanzariti (2015). "The youngest record of metriorhynchid crocodylomorphs, with implications for the extinction of Thalattosuchia". Cretaceous Research. 56: 608–616. Bibcode:2015CrRes..56..608C. doi:10.1016/j.cretres.2015.07.001. hdl:2318/1537833.
  4. ^ a b Martin, Jeremy E.; Suteethorn, S.; Lauprasert, K. (February 2019). "A new freshwater teleosaurid from the Jurassic of northeastern Thailand" (PDF). Journal of Vertebrate Paleontology. 64 (2): 239–260. doi:10.1080/02724634.2018.1549059. S2CID 91988192.
  5. ^ Spindler, Frederik; Lauer, René; Tischlinger, Helmut; Mäuser, Matthias (2021-07-05). "The integument of pelagic crocodylomorphs (Thalattosuchia: Metriorhynchidae)". Palaeontologia Electronica. 24 (2): 1–41. doi:10.26879/1099. ISSN 1094-8074.
  6. ^ Herrera, Y.; Fernandez, M.S.; Lamas, S.G.; Campos, L.; Talevi, M.; Gasparini, Z. (2017). "Morphology of the sacral region and reproductive strategies of Metriorhynchidae: a counter-inductive approach". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 106 (4): 247–255. doi:10.1017/S1755691016000165. hdl:11336/66599.
  7. ^ Wilberg, Eric W. (2015-07-01). "What's in an Outgroup? The Impact of Outgroup Choice on the Phylogenetic Position of Thalattosuchia (Crocodylomorpha) and the Origin of Crocodyliformes". Systematic Biology. 64 (4): 621–637. doi:10.1093/sysbio/syv020. ISSN 1076-836X. PMID 25840332.
  8. ^ Johnson, Michela M.; Young, Mark T.; Brusatte, Stephen L. (2020-10-08). "The phylogenetics of Teleosauroidea (Crocodylomorpha, Thalattosuchia) and implications for their ecology and evolution". PeerJ. 8: e9808. doi:10.7717/peerj.9808. ISSN 2167-8359. PMC 7548081. PMID 33083104.
  9. ^ a b c Wilberg, E. W.; Godoy, P. L.; Griffiths, E. F.; Turner, A. H.; Benson, R. B. J. (2023). "A new early diverging thalattosuchian (Crocodylomorpha) from the Early Jurassic (Pliensbachian) of Dorset, U.K. and implications for the origin and evolution of the group". Journal of Vertebrate Paleontology. 42 (3). e2161909. doi:10.1080/02724634.2022.2161909. S2CID 256149424.
  10. ^ Benani, Hicham; Nehili, Ayoub; Ouzzaouit, Lalla Amina; Jouve, Stéphane; Boudad, Larbi; Masrour, Moussa; Jalil, Noureddine; Arrad, Taha Younes (February 2023). "Discovery of the teleosauroid crocodylomorph from the early Jurassic of Chaara cave, Middle Atlas of Morocco". Journal of African Earth Sciences. 198: 104804. Bibcode:2023JAfES.19804804B. doi:10.1016/j.jafrearsci.2022.104804.
  11. ^ Young, Mark T.; Sachs, Sven (2021-09-02). "Evidence of thalattosuchian crocodylomorphs in the Portland Stone Formation (Late Jurassic) of England, and a discussion on Cretaceous teleosauroids". Historical Biology. 33 (9): 1473–1476. Bibcode:2021HBio...33.1473Y. doi:10.1080/08912963.2019.1709453. hdl:20.500.11820/34b3dd5b-bc82-4c1a-b8ee-45fa3731d244. ISSN 0891-2963. S2CID 213426116.
  12. ^ Chiarenza, Alfio A.; Foffa, Davide; Young, Mark T.; Insacco, Gianni; Cau, Andrea; Carnevale, Giorgio; Catanzariti, Rita (September 2015). "The youngest record of metriorhynchid crocodylomorphs, with implications for the extinction of Thalattosuchia". Cretaceous Research. 56: 608–616. Bibcode:2015CrRes..56..608C. doi:10.1016/j.cretres.2015.07.001. hdl:2318/1537833.

Further reading

edit
  • Fraas, E. (1902). "Die Meer-Krocodilier (Thalattosuchia) des oberen Jura unter specieller Berücksichtigung von Dacosaurus und Geosaurus". Paleontographica 49: 1-72.