Extinct genus of reptiles
Hylaeochampsa is an extinct genus of eusuchian crocodylomorphs . It is known only from a partial skull recovered from Barremian -age rocks of the Lower Cretaceous Vectis Formation (Wealden Group ) of the Isle of Wight . This skull, BMNH R 177 , is short and wide, with a eusuchian-like palate and inferred enlarged posterior teeth that would have been suitable for crushing.[2] Hylaochampsa was described by Richard Owen in 1874, with H. vectiana as the type species .[2] It may be the same genus as the slightly older Heterosuchus , inferred to have been of similar evolutionary grade , but there is no overlapping material as Heterosuchus is known only from vertebrae . If the two could be shown to be synonyms , Hylaeochampsa would have priority because it is the older name. Hylaeochampsa is the type genus of the family Hylaeochampsidae , which also includes Iharkutosuchus from the Late Cretaceous of Hungary . James Clark and Mark Norell positioned it as the sister group to Crocodylia .[3] Hylaeochampsa is currently the oldest known unambiguous eusuchian.[4]
The cladogram below results from a 2011 Buscalioni et al. phylogenetic study:[5]
References
^ Rio, Jonathan P.; Mannion, Philip D. (6 September 2021). "Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem" . PeerJ . 9 : e12094. doi :10.7717/peerj.12094 . PMC 8428266 . PMID 34567843 .
^ a b Owen, R. (1874). Monograph on the fossil Reptilia of the Wealden and Purbeck formations. Supplement no. V. Dinosauria (Iguanodon ). [Wealden and Purbeck.]. The Palaeontographical Society, London 1873:1-18
^ Clark, James M.; Norell, Mark A. (1992). "The Early Cretaceous crocodylomorph Hylaeochampsa vectiana from the Wealden of the Isle of Wight" (PDF) . American Museum Novitates (3032).
^ Brochu, Christopher A. (2003). "Phylogenetic approaches toward crocodylian history" (PDF) . Annual Review of Earth and Planetary Sciences . 31 (31): 357–397. Bibcode :2003AREPS..31..357B . doi :10.1146/annurev.earth.31.100901.141308 . S2CID 86624124 . Archived from the original (PDF) on 2019-12-31.
^ Buscalioni, A.D.; Piras, P.; Vullo, R.; Signore, M.; Barbera, C. (2011). "Early eusuchia crocodylomorpha from the vertebrate-rich Plattenkalk of Pietraroia (Lower Albian, southern Apennines, Italy)" . Zoological Journal of the Linnean Society . 163 : S199–S227. doi :10.1111/j.1096-3642.2011.00718.x .
Hylaeochampsa Hylaeochampsa vectiana