The genus was named in 1995 from fossils found from the Placerias quarry of the Chinle Group in Apache County, Arizona.[1] It was named after the paleontologist J. Michael Parrish, with the type species being P. mccreai. Parrishia was distinguished from the closely related genus Hesperosuchus on the basis of more robust vertebral centra and the lack of dorsoventrally offset articular faces of the cervical centra, thus causing the neck to be straight rather than anterodorsally curved as in Hesperosuchus.[1]
In their description of a new crocodylomorph skeleton from the famous Whitaker quarry in Ghost Ranch, Clark et al. (2000) treated Parrishia as a nomen dubium because they considered the holotype and referred specimens undiagnostic.[2] More complete postcranial skeletons such as PEFO 26681 have been found that clearly show that the cervical centra of Parrishia possess articular faces that are dorsoventrally offset as in Hesperosuchus.[3] Additionally, in the holotype specimen (UCMP A269/139623) the anterior surfaces of the centa are positioned more dorsally than the posterior surfaces, giving the neck an anterodorsal curve like Hesperosuchus.[2][4] Therefore, the only distinguishing character that distinguishes Parrishia from Hesperosuchus is the robustness of the vertebrae.[3] Material from Parrishia cannot be assigned to any other known sphenosuchian genus because of the lack of postcranial apomorphies; as a result, it is considered an indeterminate genus.[5]
In an SVP 2018 conference abstract, William Parker and colleagues reported the discovery of new specimens indicating that Parrishia represents a phytosaur and not a crocodylomorph.[6]
Referencesedit
^ abLong, R. A.; Murry, P. A. (1995). "Late Triassic (Carnian and Norian) tetrapods from the southwestern United States". New Mexico Museum of Natural History and Science Bulletin. 4: 1–254.
^ abClark, J. M.; Sues, H.-D.; Berman, D. S. (2000). "A new specimen of Hesperosuchus agilis from the Upper Triassic of New Mexico and the interrelationships of basal crocodylomorph archosaurs". Journal of Vertebrate Paleontology. 20 (4): 683–704. doi:10.1671/0272-4634(2000)020[0683:ANSOHA]2.0.CO;2. S2CID 7455338.
^ abParker, W. G.; Irmis, R. B. (2005). "Advances in Late Triassic vertebrate paleontology based on new material from Petrified Forest National Park, Arizona". In Heckert, A. B.; Lucas, S. G. (eds.). Vertebrate Paleontology in Arizona. New Mexico Museum of Natural History and Science Bulletin. Vol. 29. Albuquerque, New Mexico: New Mexico Museum of Natural History and Science. pp. 45–58.
^Colbert, E. H. (1952). "A pseudosuchian reptile from Arizona". Bulletin of the American Museum of Natural History. 99: 561–592.
^Irmis, R. B. (2005). "The vertebrate fauna of the Upper Triassic Chinle Formation in Northern Arizona". In Sterling J. Nesbitt; William G. Parker; Randall B. Irmis (eds.). Guidebook to the Triassic Formations of the Colorado Plateau in Northern Arizona: Geology, Paleontology, and History. Vol. 9. Bulletin of the Mesa Southwest Museum.
parrishia, extinct, genus, sphenosuchian, crocodylomorph, known, from, late, triassic, chinle, dockum, santa, rosa, formations, arizona, mexico, temporal, range, late, triassic, preꞒ, scientific, classification, domain, eukaryota, kingdom, animalia, phylum, ch. Parrishia is an extinct genus of sphenosuchian crocodylomorph known from the Late Triassic Chinle Dockum and Santa Rosa Formations in Arizona and New Mexico ParrishiaTemporal range Late Triassic 221 5 205 6 Ma PreꞒ Ꞓ O S D C P T J K Pg N Scientific classification Domain Eukaryota Kingdom Animalia Phylum Chordata Class Reptilia Clade Archosauria Clade Pseudosuchia Clade Crocodylomorpha Genus ParrishiaLong and Murry 1995 Type species P mccreaiLong and Murry 1995Discovery and naming editThe genus was named in 1995 from fossils found from the Placerias quarry of the Chinle Group in Apache County Arizona 1 It was named after the paleontologist J Michael Parrish with the type species being P mccreai Parrishia was distinguished from the closely related genus Hesperosuchus on the basis of more robust vertebral centra and the lack of dorsoventrally offset articular faces of the cervical centra thus causing the neck to be straight rather than anterodorsally curved as in Hesperosuchus 1 In their description of a new crocodylomorph skeleton from the famous Whitaker quarry in Ghost Ranch Clark et al 2000 treated Parrishia as a nomen dubium because they considered the holotype and referred specimens undiagnostic 2 More complete postcranial skeletons such as PEFO 26681 have been found that clearly show that the cervical centra of Parrishia possess articular faces that are dorsoventrally offset as in Hesperosuchus 3 Additionally in the holotype specimen UCMP A269 139623 the anterior surfaces of the centa are positioned more dorsally than the posterior surfaces giving the neck an anterodorsal curve like Hesperosuchus 2 4 Therefore the only distinguishing character that distinguishes Parrishia from Hesperosuchus is the robustness of the vertebrae 3 Material from Parrishia cannot be assigned to any other known sphenosuchian genus because of the lack of postcranial apomorphies as a result it is considered an indeterminate genus 5 In an SVP 2018 conference abstract William Parker and colleagues reported the discovery of new specimens indicating that Parrishia represents a phytosaur and not a crocodylomorph 6 References edit a b Long R A Murry P A 1995 Late Triassic Carnian and Norian tetrapods from the southwestern United States New Mexico Museum of Natural History and Science Bulletin 4 1 254 a b Clark J M Sues H D Berman D S 2000 A new specimen of Hesperosuchus agilis from the Upper Triassic of New Mexico and the interrelationships of basal crocodylomorph archosaurs Journal of Vertebrate Paleontology 20 4 683 704 doi 10 1671 0272 4634 2000 020 0683 ANSOHA 2 0 CO 2 S2CID 7455338 a b Parker W G Irmis R B 2005 Advances in Late Triassic vertebrate paleontology based on new material from Petrified Forest National Park Arizona In Heckert A B Lucas S G eds Vertebrate Paleontology in Arizona New Mexico Museum of Natural History and Science Bulletin Vol 29 Albuquerque New Mexico New Mexico Museum of Natural History and Science pp 45 58 Colbert E H 1952 A pseudosuchian reptile from Arizona Bulletin of the American Museum of Natural History 99 561 592 Irmis R B 2005 The vertebrate fauna of the Upper Triassic Chinle Formation in Northern Arizona In Sterling J Nesbitt William G Parker Randall B Irmis eds Guidebook to the Triassic Formations of the Colorado Plateau in Northern Arizona Geology Paleontology and History Vol 9 Bulletin of the Mesa Southwest Museum Program booklet vertpaleo org 2018 Retrieved 2020 02 06 Portal nbsp Paleontology nbsp This article about a prehistoric archosaur is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Parrishia amp oldid 1094627263, wikipedia, wiki, book, books, library,
