{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T20:00:53Z","timestamp":1791489653513,"version":"4.3.4"},"reference-count":83,"publisher":"Springer Science and Business Media LLC","issue":"4","license":[{"start":{"date-parts":[[2021,7,2]],"date-time":"2021-07-02T00:00:00Z","timestamp":1625184000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,7,2]],"date-time":"2021-07-02T00:00:00Z","timestamp":1625184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Nat"],"published-print":{"date-parts":[[2021,8]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>The <jats:italic>Placerias<\/jats:italic>\/Downs\u2019 Quarry complex in eastern Arizona, USA, is the most diverse Upper Triassic vertebrate locality known. We report a new short-faced archosauriform, <jats:italic>Syntomiprosopus sucherorum<\/jats:italic> gen. et sp. nov., represented by four incomplete mandibles, that expands that diversity with a morphology unique among Late Triassic archosauriforms. The most distinctive feature of <jats:italic>Syntomiprosopus<\/jats:italic> gen. nov. is its anteroposteriorly short, robust mandible with 3\u20134 anterior, a larger caniniform, and 1\u20133 \u201cpostcanine\u201d alveoli. The size and shape of the alveoli and the preserved tips of replacement teeth preclude assignment to any taxon known only from teeth. Additional autapomorphies of <jats:italic>S. sucherorum<\/jats:italic> gen. et sp. nov. include a large fossa associated with the mandibular fenestra, an interdigitating suture of the surangular with the dentary, fine texture ornamenting the medial surface of the splenial, and a surangular ridge that completes a 90\u00b0 arc. The external surfaces of the mandibles bear shallow, densely packed, irregular, fine pits and narrow, arcuate grooves. This combination of character states allows an archosauriform assignment; however, an associated and similarly sized braincase indicates that <jats:italic>Syntomiprosopus<\/jats:italic> n. gen. may represent previously unsampled disparity in early-diverging crocodylomorphs. The <jats:italic>Placerias<\/jats:italic> Quarry is Adamanian (Norian, maximum depositional age ~219 Ma), and this specimen appears to be an early example of shortening of the skull, which occurs later in diverse archosaur lineages, including the Late Cretaceous crocodyliform <jats:italic>Simosuchus<\/jats:italic>. This is another case where Triassic archosauriforms occupied morphospace converged upon by other archosaurs later in the Mesozoic and further demonstrates that even well-sampled localities can yield new taxa.<\/jats:p>","DOI":"10.1007\/s00114-021-01733-1","type":"journal-article","created":{"date-parts":[[2021,7,2]],"date-time":"2021-07-02T05:02:34Z","timestamp":1625202154000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A new short-faced archosauriform from the Upper Triassic Placerias\/Downs\u2019 quarry complex, Arizona, USA, expands the morphological diversity of the Triassic archosauriform radiation"],"prefix":"10.1007","volume":"108","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9240-6267","authenticated-orcid":false,"given":"Andrew B.","family":"Heckert","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7017-1652","authenticated-orcid":false,"given":"Sterling J.","family":"Nesbitt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6473-8691","authenticated-orcid":false,"given":"Michelle R.","family":"Stocker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vince P.","family":"Schneider","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9241-8038","authenticated-orcid":false,"given":"Devin K.","family":"Hoffman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7845-748X","authenticated-orcid":false,"given":"Brian W.","family":"Zimmer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,7,2]]},"reference":[{"key":"1733_CR1","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1111\/j.1096-3642.1985.tb01796.x","volume":"84","author":"MJ Benton","year":"1985","unstructured":"Benton MJ (1985) Classification and phylogeny of the diapsid reptiles. Zool J Linnean Soc 84:97\u2013164","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR2","doi-asserted-by":"publisher","unstructured":"Brown CM, Collin SV, Derek WL, Kirstin SB, Nicol\u00e1s EC, Matthew JV, David CE (2015) Tooth counts through growth in diapsid reptiles: implications for interpreting individual and size-related variation in the fossil record. J Anat 226:322\u2013333. https:\/\/doi.org\/10.1111\/joa.12280","DOI":"10.1111\/joa.12280"},{"key":"1733_CR3","doi-asserted-by":"publisher","first-page":"3","DOI":"10.1080\/14772010903537732","volume":"8","author":"SL Brusatte","year":"2010","unstructured":"Brusatte SL, Benton MJ, Desojo JB, Langer MC (2010) The higher-level phylogeny of Archosauria (Tetrapoda: Diapsida). J Syst Palaeontol 8:3\u201347. https:\/\/doi.org\/10.1080\/14772010903537732","journal-title":"J Syst Palaeontol"},{"key":"1733_CR4","doi-asserted-by":"publisher","first-page":"941","DOI":"10.1038\/35016061","volume":"405","author":"GA Buckley","year":"2000","unstructured":"Buckley GA, Brochu CA, Krause DW, Pol D (2000) A pug-nosed crocodyliform from the Late Cretaceous of Madagascar. Nature 405:941\u2013944","journal-title":"Nature"},{"key":"1733_CR5","first-page":"255","volume":"13","author":"CL Camp","year":"1956","unstructured":"Camp CL, Welles SP (1956) Triassic dicynodont reptiles. Mem Univ Calif 13:255\u2013348","journal-title":"Mem Univ Calif"},{"key":"1733_CR6","doi-asserted-by":"publisher","first-page":"497","DOI":"10.1080\/02724634.1999.10011161","volume":"19","author":"TD Carr","year":"1999","unstructured":"Carr TD (1999) Craniofacial ontogeny in Tyrannosauridae (Dinosauria, Coelurosauria). J Vertebr Paleontol 19:497\u2013520","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR7","doi-asserted-by":"publisher","first-page":"e9192","DOI":"10.7717\/peerj.9192","volume":"8","author":"TD Carr","year":"2020","unstructured":"Carr TD (2020) A high-resolution growth series of Tyrannosaurus rex obtained from multiple lines of evidence. PeerJ 8:e9192. https:\/\/doi.org\/10.7717\/peerj.9192","journal-title":"PeerJ"},{"key":"1733_CR8","first-page":"274","volume":"9","author":"S Chatterjee","year":"1993","unstructured":"Chatterjee S (1993) Shuvosaurus, a new theropod. Natl Geogra Res Explor 9:274\u2013285","journal-title":"Natl Geogra Res Explor"},{"key":"1733_CR9","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/14772019.2013.781067","volume":"12","author":"JN Choiniere","year":"2013","unstructured":"Choiniere JN, Clark JM, Forster CA, Norell MA, Eberth DA, Erickson GM, Chu H, Xu X (2013) A juvenile specimen of a new coelurosaur (Dinosauria: Theropoda) from the Middle-Late Jurassic Shishugou Formation of Xinjiang, People's Republic of China. J Syst Palaeontol 12:1\u201339. https:\/\/doi.org\/10.1080\/14772019.2013.781067","journal-title":"J Syst Palaeontol"},{"key":"1733_CR10","doi-asserted-by":"publisher","first-page":"77","DOI":"10.1046\/j.1096-3642.2002.00026.x","volume":"136","author":"JM Clark","year":"2002","unstructured":"Clark JM, Sues H-D (2002) Two new basal crocodylomorph archosaurs from the Lower Jurassic and the monophyly of the Sphenosuchia. Zool J Linnean Soc 136:77\u201395","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR11","doi-asserted-by":"publisher","first-page":"683","DOI":"10.1671\/0272-4634(2000)020[0683:ANSOHA]2.0.CO;2","volume":"20","author":"JM Clark","year":"2001","unstructured":"Clark JM, Sues H-D, Berman DS (2001) A new specimen of Hesperosuchus agilis from the Upper Triassic of New Mexico and the interrelationships of basal crocodylomorph archosaurs. J Vertebr Paleontol 20:683\u2013704","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR12","doi-asserted-by":"publisher","first-page":"1021","DOI":"10.1038\/nature02802","volume":"430","author":"JM Clark","year":"2004","unstructured":"Clark JM, Xu X, Forster CA, Wang Y (2004) A Middle Jurassic \u2018sphenosuchian\u2019 from China and the origin of the crocodylian skull. Nature 430:1021\u20131024. https:\/\/doi.org\/10.1038\/nature02802","journal-title":"Nature"},{"key":"1733_CR13","first-page":"160","volume":"57","author":"EH Colbert","year":"1989","unstructured":"Colbert EH (1989) The Triassic dinosaur Coelophysis. Mus North Ariz Bull 57:160","journal-title":"Mus North Ariz Bull"},{"key":"1733_CR14","doi-asserted-by":"publisher","first-page":"839","DOI":"10.1111\/j.1096-3642.2010.00655.x","volume":"161","author":"JB Desojo","year":"2011","unstructured":"Desojo JB, Ezcurra MD, Schultz CL (2011) An unusual new archosauriform from the Middle\u2013Late Triassic of southern Brazil and the monophyly of Doswelliidae. Zool J Linnean Soc 161:839\u2013871. https:\/\/doi.org\/10.1111\/j.1096-3642.2010.00655.x","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR15","doi-asserted-by":"publisher","first-page":"653","DOI":"10.1080\/08912963.2017.1387110","volume":"31","author":"KN Dollman","year":"2019","unstructured":"Dollman KN, Viglietti PA, Choiniere JN (2019) A new specimen of Orthosuchus stormbergi (Nash 1968) and a review of the distribution of Southern African Lower Jurassic crocodylomorphs. Hist Biol 31:653\u2013664. https:\/\/doi.org\/10.1080\/08912963.2017.1387110","journal-title":"Hist Biol"},{"key":"1733_CR16","doi-asserted-by":"publisher","first-page":"e1778","DOI":"10.7717\/peerj.1778","volume":"4","author":"MD Ezcurra","year":"2016","unstructured":"Ezcurra MD (2016) The phylogenetic relationships of basal archosauromorphs, with an emphasis on the systematics of proterosuchian archosauriforms. PeerJ 4:e1778. https:\/\/doi.org\/10.7717\/peerj.1778","journal-title":"PeerJ"},{"key":"1733_CR17","doi-asserted-by":"publisher","first-page":"e89165","DOI":"10.1371\/journal.pone.0089165","volume":"9","author":"MD Ezcurra","year":"2014","unstructured":"Ezcurra MD, Scheyer TM, Butler RJ (2014) The origin and early evolution of Sauria: reassessing the Permian saurian fossil record and the timing of the crocodile-lizard divergence. PLoS One 9:e89165","journal-title":"PLoS One"},{"key":"1733_CR18","first-page":"133","volume":"3","author":"AR Fiorillo","year":"1993","unstructured":"Fiorillo AR, Padian K (1993) Taphonomy of the Late Triassic Placerias quarry (Petrified Forest Member, Chinle Formation) of eastern Arizona. N M Mus Nat Hist Sci Bull 3:133\u2013134","journal-title":"N M Mus Nat Hist Sci Bull"},{"key":"1733_CR19","doi-asserted-by":"publisher","first-page":"373","DOI":"10.1669\/0883-1351(2000)015<0373:TADSOT>2.0.CO;2","volume":"15","author":"AR Fiorillo","year":"2000","unstructured":"Fiorillo AR, Padian K, Musikasinthorn C (2000) Taphonomy and depositional setting of the Placerias quarry (Chinle Formation: Late Triassic, Arizona). Palaios 15:373\u2013386","journal-title":"Palaios"},{"key":"1733_CR20","doi-asserted-by":"publisher","unstructured":"Ford DP, Benson RBJ (2019) A redescription of Orovenator mayorum (Sauropsida, Diapsida) using high-resolution \u03bcCT, and the consequences for early amniote phylogeny. Pap Palaeontol 0. https:\/\/doi.org\/10.1002\/spp2.1236","DOI":"10.1002\/spp2.1236"},{"key":"1733_CR21","volume-title":"Dawn of the dinosaurs: life in the Triassic. Life of the Past","author":"NC Fraser","year":"2006","unstructured":"Fraser NC (2006) Dawn of the dinosaurs: life in the Triassic. Life of the Past. Indiana University Press, Bloomington"},{"key":"1733_CR22","doi-asserted-by":"publisher","first-page":"105","DOI":"10.1111\/j.1096-0031.1988.tb00514.x","volume":"4","author":"J Gauthier","year":"1988","unstructured":"Gauthier J, Kluge AG, Rowe T (1988) Amniote phylogeny and the importance of fossils. Cladistics 4:105\u2013209","journal-title":"Cladistics"},{"key":"1733_CR23","doi-asserted-by":"publisher","first-page":"49","DOI":"10.1046\/j.1096-3642.2002.00025.x","volume":"136","author":"DJ Gower","year":"2002","unstructured":"Gower DJ (2002) Braincase evolution in suchian archosaurs (Reptilia: Diapsida): evidence from the rauisuchian Batrachotomus kupferzellensis. Zool J Linnean Soc 136:49\u201376","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR24","doi-asserted-by":"publisher","first-page":"7","DOI":"10.1046\/j.1096-3642.2002.00023.x","volume":"136","author":"DJ Gower","year":"2002","unstructured":"Gower DJ, Walker AD (2002) New data on the braincase of the aetosaurian archosaur (Reptilia: Diapsida) Stagonolepis robertsoni Agassiz. Zool J Linnean Soc 136:7\u201323","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR25","first-page":"253","volume":"21","author":"AB Heckert","year":"2002","unstructured":"Heckert AB (2002) A revision of the Upper Triassic ornithischian dinosaur Revueltosaurus, with a description of a new species. N M Mus Nat Hist Sci Bull 21:253\u2013268","journal-title":"N M Mus Nat Hist Sci Bull"},{"key":"1733_CR26","first-page":"1","volume":"27","author":"AB Heckert","year":"2004","unstructured":"Heckert AB (2004) Late Triassic microvertebrates from the lower Chinle Group (Otischalkian-Adamanian: Carnian), southwestern U.S.A. N M Mus Nat Hist Sci Bull 27:1\u2013170","journal-title":"N M Mus Nat Hist Sci Bull"},{"key":"1733_CR27","first-page":"77","volume":"29","author":"AB Heckert","year":"2005","unstructured":"Heckert AB (2005) Krzyzanowskisaurus, a new name for a probable ornithischian dinosaur from the Upper Triassic Chinle Group, Arizona and New Mexico. N M Mus Nat Hist Sci Bull 29:77\u201383","journal-title":"N M Mus Nat Hist Sci Bull"},{"key":"1733_CR28","first-page":"11","volume":"1","author":"AB Heckert","year":"1997","unstructured":"Heckert AB, Lucas SG (1997) Lower Chinle Group (Adamanian: latest Carnian) tetrapod biostratigraphy and biochronology, eastern Arizona and west-central New Mexico. Southwest Paleontol Symp Proc 1:11\u201323","journal-title":"Southwest Paleontol Symp Proc"},{"key":"1733_CR29","first-page":"281","volume":"54","author":"AB Heckert","year":"2003","unstructured":"Heckert AB, Lucas SG (2003) Stratigraphy and paleontology of the lower Chinle Group (Adamanian: latest Carnian) in the vicinity of St. Johns, Arizona. N M Geol Soc Guideb 54:281\u2013288","journal-title":"N M Geol Soc Guideb"},{"key":"1733_CR30","first-page":"123","volume":"41","author":"AB Heckert","year":"2009","unstructured":"Heckert AB, Lucas SG, Dickinson WR, Mortensen JK (2009) New ID-TIMS U-Pb ages for Chinle Group strata (Upper Triassic) in New Mexico and Arizona, correlation to the Newark Supergroup, and implications for the \u201clong Norian\u201d. Geol Soc Am Abstr Programs 41:123","journal-title":"Geol Soc Am Abstr Programs"},{"key":"1733_CR31","doi-asserted-by":"publisher","first-page":"1333","DOI":"10.1111\/j.1475-4983.2012.01200.x","volume":"55","author":"AB Heckert","year":"2012","unstructured":"Heckert AB, Lucas SG, Spielmann JA (2012) A new species of the enigmatic archosauromorph Doswellia from the Upper Triassic Bluewater Creek Formation, New Mexico, USA. Palaeontology 55:1333\u20131348","journal-title":"Palaeontology"},{"key":"1733_CR32","doi-asserted-by":"publisher","first-page":"555","DOI":"10.1144\/SP379.2","volume":"379","author":"CM Holliday","year":"2013","unstructured":"Holliday CM, Nesbitt SJ (2013) Morphology and diversity of the mandibular symphysis of archosauriforms. Geol Soc Lond, Spec Publ 379:555\u2013571","journal-title":"Geol Soc Lond, Spec Publ"},{"key":"1733_CR33","doi-asserted-by":"publisher","first-page":"715","DOI":"10.1671\/039.029.0330","volume":"29","author":"CM Holliday","year":"2009","unstructured":"Holliday CM, Witmer LM (2009) The epipterygoid of crocodyliforms and its significance for the evolution of the orbitotemporal region of Eusuchians. J Vertebr Paleontol 29:715\u2013733. https:\/\/doi.org\/10.1671\/039.029.0330","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR34","first-page":"268","volume":"65","author":"F Huene","year":"1946","unstructured":"Huene F (1946) Die grossen St\u00e4mme der Tetrapoden in den geologischen Zeiten. Biologisches Zentralbl 65:268\u2013275","journal-title":"Biologisches Zentralbl"},{"key":"1733_CR35","doi-asserted-by":"publisher","first-page":"511","DOI":"10.1016\/S0016-6995(98)80123-X","volume":"31","author":"AP Hunt","year":"1998","unstructured":"Hunt AP, Lucas SG, Heckert AB, Sullivan RM, Lockley MG (1998) Late Triassic dinosaurs from the western United States. Geobios 31:511\u2013531","journal-title":"Geobios"},{"key":"1733_CR36","doi-asserted-by":"publisher","first-page":"1339","DOI":"10.1139\/e05-031","volume":"42","author":"RB Irmis","year":"2005","unstructured":"Irmis RB, Parker WG (2005) Unusual tetrapod teeth from the Upper Triassic Chinle Formation, Arizona, USA. Can J Earth Sci 42:1339\u20131345","journal-title":"Can J Earth Sci"},{"key":"1733_CR37","doi-asserted-by":"publisher","first-page":"3","DOI":"10.1080\/08912960600719988","volume":"19","author":"RB Irmis","year":"2007","unstructured":"Irmis RB, Parker WG, Nesbitt SJ, Liu J (2007) Early ornithischian dinosaurs: the Triassic record. Hist Biol 19:3\u201322","journal-title":"Hist Biol"},{"key":"1733_CR38","doi-asserted-by":"publisher","first-page":"258","DOI":"10.1016\/j.epsl.2011.07.015","volume":"309","author":"RB Irmis","year":"2011","unstructured":"Irmis RB, Mundil R, Martz JW, Parker WG (2011) High-resolution U-Pb ages from the Upper Triassic Chinle Formation (New Mexico, USA) support a diachronous rise of dinosaurs. Earth Planet Sci Lett 309:258\u2013267. https:\/\/doi.org\/10.1016\/j.epsl.2011.07.015","journal-title":"Earth Planet Sci Lett"},{"key":"1733_CR39","first-page":"55","volume-title":"Aspects of vertebrate history","author":"LL Jacobs","year":"1980","unstructured":"Jacobs LL, Murry PA (1980) The vertebrate community of the Triassic Chinle Formation near St. Johns, Arizona. In: Jacobs LL (ed) Aspects of vertebrate history. Museum of Northern Arizona, Flagstaff, pp 55\u201373"},{"key":"1733_CR40","first-page":"171","volume-title":"In the shadow of dinosaurs: early Mesozoic tetrapods","author":"FT Kaye","year":"1994","unstructured":"Kaye FT, Padian K (1994) Microvertebrates from the Placerias quarry: a window on Late Triassic vertebrate diversity in the American Southwest. In: Fraser NC, Sues H-D (eds) In the shadow of dinosaurs: early Mesozoic tetrapods. Cambridge University Press, Cambridge, pp 171\u2013196"},{"key":"1733_CR41","doi-asserted-by":"publisher","first-page":"4654","DOI":"10.1029\/2019GC008474","volume":"20","author":"DV Kent","year":"2019","unstructured":"Kent DV, Olsen PE, Lepre C, Rasmussen C, Mundil R, Gehrels GE, Giesler D, Irmis RB, Geissman JW, Parker WG (2019) Magnetochronology of the entire Chinle Formation (Norian age) in a scientific drill core from Petrified Forest National Park (Arizona, USA) and implications for regional and global correlations in the Late Triassic. Geochem Geophys Geosyst 20:4654\u20134664. https:\/\/doi.org\/10.1029\/2019GC008474","journal-title":"Geochem Geophys Geosyst"},{"key":"1733_CR42","doi-asserted-by":"publisher","first-page":"13","DOI":"10.1080\/02724634.2010.532674","volume":"30","author":"NJ Kley","year":"2010","unstructured":"Kley NJ, Sertich JJW, Turner AH, Krause DW, O'Connor PM, Georgi JA (2010) Craniofacial morphology of Simosuchus clarki (Crocodyliformes: Notosuchia) from the Late Cretaceous of Madagascar. J Vertebr Paleontol 30:13\u201398","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR43","doi-asserted-by":"publisher","first-page":"e2801","DOI":"10.7717\/peerj.2801","volume":"5","author":"JM Leardi","year":"2017","unstructured":"Leardi JM, Pol D, Clark JM (2017) Detailed anatomy of the braincase of Macelognathus vagans Marsh, 1884 (Archosauria, Crocodylomorpha) using high resolution tomography and new insights on basal crocodylomorph phylogeny. PeerJ 5:e2801. https:\/\/doi.org\/10.7717\/peerj.2801","journal-title":"PeerJ"},{"key":"1733_CR44","doi-asserted-by":"publisher","unstructured":"Leardi JM, Pol D, Clark JM (2020) Braincase anatomy of Almadasuchus figarii (Archosauria, Crocodylomorpha) and a review of the cranial pneumaticity in the origins of Crocodylomorpha. J Anat. https:\/\/doi.org\/10.1111\/joa.13171","DOI":"10.1111\/joa.13171"},{"key":"1733_CR45","unstructured":"Long RA, Murry PA (1995) Late Triassic (Carnian and Norian) tetrapods from the southwestern United States. N M Mus Nat Hist Sci Bull 4 254 p"},{"key":"1733_CR46","first-page":"65","volume-title":"Dawn of the age of dinosaurs in the American Southwest","author":"RA Long","year":"1989","unstructured":"Long RA, Lucas SG, Hunt AP, McCrea RT (1989) Charles Camp: collecting Late Triassic vertebrates in the American Southwest during the 1920\u2019s and 1930\u2019s. In: Lucas SG, Hunt AP (eds) Dawn of the age of dinosaurs in the American Southwest. New Mexico Museum of Natural History, Albuquerque, pp 65\u201371"},{"key":"1733_CR47","doi-asserted-by":"publisher","first-page":"171","DOI":"10.1007\/BF01134434","volume":"79","author":"SG Lucas","year":"1992","unstructured":"Lucas SG, Hunt AP, Long RA (1992) The oldest dinosaurs. Naturwissenschaften 79:171\u2013172","journal-title":"Naturwissenschaften"},{"key":"1733_CR48","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1127\/njgpa\/203\/1997\/23","volume":"203","author":"SG Lucas","year":"1997","unstructured":"Lucas SG, Heckert AB, Hunt AP (1997) Lithostratigraphy and biostratigraphic significance of the Placerias quarry, east-central Arizona. Neues Jb Geol Pal\u00e4ontol Abh 203:23\u201346","journal-title":"Neues Jb Geol Pal\u00e4ontol Abh"},{"key":"1733_CR49","doi-asserted-by":"publisher","first-page":"1128","DOI":"10.1130\/GES02004.1","volume":"15","author":"AD Marsh","year":"2019","unstructured":"Marsh AD, Parker WG, Stockli DF, Martz JW (2019) Regional correlation of the Sonsela Member (Upper Triassic Chinle Formation) and detrital U-Pb zircon data from the Sonsela Sandstone bed near the Sonsela Buttes, northeastern Arizona, USA, support the presence of a distributive fluvial system. Geosphere 15:1128\u20131139. https:\/\/doi.org\/10.1130\/GES02004.1","journal-title":"Geosphere"},{"key":"1733_CR50","doi-asserted-by":"publisher","unstructured":"Mayr GH, Hurum J (2020) A tiny, long-legged raptor from the early Oligocene of Poland may be the earliest bird-eating diurnal bird of prey. Sci Nat 107:48. https:\/\/doi.org\/10.1007\/s00114-020-01703-z","DOI":"10.1007\/s00114-020-01703-z"},{"key":"1733_CR51","doi-asserted-by":"publisher","first-page":"1117","DOI":"10.1007\/s00114-010-0729-0","volume":"97","author":"JS Mitchell","year":"2010","unstructured":"Mitchell JS, Heckert AB, Sues H-D (2010) Grooves to tubes: evolution of the venom delivery system in a Late Triassic \"reptile\". Naturwissenschaften 97:1117\u20131121. https:\/\/doi.org\/10.1007\/s00114-010-0729-0","journal-title":"Naturwissenschaften"},{"key":"1733_CR52","doi-asserted-by":"publisher","first-page":"773","DOI":"10.1017\/S0022336000029127","volume":"61","author":"PA Murry","year":"1987","unstructured":"Murry PA (1987) New reptiles from the Upper Triassic Chinle Formation of Arizona. J Paleontol Mem 61:773\u2013786","journal-title":"J Paleontol Mem"},{"key":"1733_CR53","doi-asserted-by":"publisher","first-page":"84","DOI":"10.1206\/0003-0090(2007)302[1:TAOEOA]2.0.CO;2","volume":"302","author":"SJ Nesbitt","year":"2007","unstructured":"Nesbitt SJ (2007) The anatomy of Effigia okeeffeae (Archosauria, Suchia), theropod-like convergence, and the distribution of related taxa. Bull Am Mus Nat Hist 302:84","journal-title":"Bull Am Mus Nat Hist"},{"key":"1733_CR54","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1206\/352.1","volume":"352","author":"SJ Nesbitt","year":"2011","unstructured":"Nesbitt SJ (2011) The early evolution of archosaurs: relationships and the origin of major clades. Bull Am Mus Nat Hist 352:1\u2013292","journal-title":"Bull Am Mus Nat Hist"},{"key":"1733_CR55","doi-asserted-by":"publisher","first-page":"1045","DOI":"10.1098\/rspb.2005.3426","volume":"273","author":"SJ Nesbitt","year":"2006","unstructured":"Nesbitt SJ, Norell MA (2006) Extreme convergence in the body plans of an early suchian (Archosauria) and ornithomimid dinosaurs (Theropoda). Proc R Soc B 273:1045\u20131048","journal-title":"Proc R Soc B"},{"key":"1733_CR56","doi-asserted-by":"publisher","first-page":"815","DOI":"10.1111\/j.1096-3642.2009.00530.x","volume":"157","author":"SJ Nesbitt","year":"2009","unstructured":"Nesbitt SJ, Stocker MR, Small BJ, Downs A (2009) The osteology and relationships of Vancleavea campi (Reptilia:Archosauriformes). Zool J Linnean Soc 157:815\u2013864","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR57","volume-title":"Anatomy, phylogeny, and palaeobiology of early archosaurs and their kin vol 379","year":"2013","unstructured":"Nesbitt SJ, Desojo JB, Irmis RB (eds) (2013) Anatomy, phylogeny, and palaeobiology of early archosaurs and their kin vol 379. Geological Society, London, Special Publications, London"},{"key":"1733_CR58","doi-asserted-by":"publisher","first-page":"484","DOI":"10.1038\/nature22037","volume":"544","author":"SJ Nesbitt","year":"2017","unstructured":"Nesbitt SJ, Butler RJ, Ezcurra MD, Barrett PM, Stocker MR, Angielczyk KD, Smith RMH, Sidor CA, Nied\u017awiedzki G, Sennikov AG, Charig AJ (2017a) The earliest bird-line archosaurs and the assembly of the dinosaur body plan. Nature 544:484\u2013487. https:\/\/doi.org\/10.1038\/nature22037","journal-title":"Nature"},{"key":"1733_CR59","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1080\/02724634.2017.1393431","volume":"37","author":"SJ Nesbitt","year":"2017","unstructured":"Nesbitt SJ, Stocker MR, Parker WG, Wood TA, Sidor CA, Angielczyk KD (2017b) The braincase and endocast of Parringtonia gracilis, a Middle Triassic suchian (Archosauria: Pseudosuchia). J Vertebr Paleontol 37:122\u2013141. https:\/\/doi.org\/10.1080\/02724634.2017.1393431","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR60","first-page":"1","volume":"179","author":"PE Olsen","year":"1979","unstructured":"Olsen PE (1979) A new aquatic eosuchian from the Newark Supergroup (Late Triassic-Early Jurassic) of North Carolina and Virginia. Postilla 179:1\u201314","journal-title":"Postilla"},{"key":"1733_CR61","doi-asserted-by":"publisher","first-page":"e4291","DOI":"10.7717\/peerj.4291","volume":"6","author":"WG Parker","year":"2018","unstructured":"Parker WG (2018) Redescription of Calyptosuchus (Stagonolepis) wellesi (Archosauria: Pseudosuchia: Aetosauria) from the Late Triassic of the Southwestern United States with a discussion of genera in vertebrate paleontology. PeerJ 6:e4291. https:\/\/doi.org\/10.7717\/peerj.4291","journal-title":"PeerJ"},{"key":"1733_CR62","first-page":"963","volume":"272","author":"WG Parker","year":"2005","unstructured":"Parker WG, Irmis RB, Nesbitt SJ, Martz JW, Browne LS (2005) The Late Triassic pseudosuchian Revueltosaurus callenderi and its implications of the diversity of early ornithischian dinosaurs. Proc R Soc Lond B 272:963\u2013969","journal-title":"Proc R Soc Lond B"},{"key":"1733_CR63","doi-asserted-by":"publisher","first-page":"e911186","DOI":"10.1080\/02724634.2014.911186","volume":"35","author":"AC Pritchard","year":"2015","unstructured":"Pritchard AC, Turner AH, Nesbitt SJ, Irmis RB, Smith ND (2015) Late Triassic tanystropheid (Reptilia, Archosauromorpha) remains from northern New Mexico (Petrified Forest Member, Chinle Formation): insights into distribution, morphology, and paleoecology of Tanystropheidae. J Vertebr Paleontol 35:e911186","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR64","doi-asserted-by":"publisher","first-page":"981","DOI":"10.2475\/06.2014.01J","volume":"314","author":"J Ramezani","year":"2014","unstructured":"Ramezani J, Fastovsky DE, Bowring SA (2014) Revised chronostratigraphy of the Lower Chinle Formation strata in Arizona and New Mexico (USA): high-precision U-PB geochronological constraints on the Late Triassic evolution of dinosaurs. Am J Sci 314:981\u20131008. https:\/\/doi.org\/10.2475\/06.2014.01J","journal-title":"Am J Sci"},{"key":"1733_CR65","doi-asserted-by":"publisher","unstructured":"Rasmussen C, Mundil R, Irmis RB, Geisler, D, Gehrels GE, Olsen PE, Kent DV, Lepre C, Kinney ST, Geissman JW and Parker WG (2020) U-Pb zircon geochronology and depositional age models for the Upper Triassic Chinle Formation (Petrified Forest National Park, Arizona, USA): Implications for Late Triassic paleoecological and paleoenvironmental change. GSA Bull 133:539\u2013558. https:\/\/doi.org\/10.1130\/B35485.1","DOI":"10.1130\/B35485.1"},{"key":"1733_CR66","unstructured":"Richard SM, Reynolds SJ, Spencer JE, Pearthree PA (2002) Digital graphics files for the Geologic Map of Arizona, a representation of Arizona Geological Survey Map 35, v. 1.0, 1.0 edn. Arizona Geological Survey. https:\/\/repository.arizona.edu\/handle\/10150\/630886"},{"key":"1733_CR67","doi-asserted-by":"publisher","first-page":"339","DOI":"10.1002\/jmor.1051670308","volume":"167","author":"R Scapino","year":"1981","unstructured":"Scapino R (1981) Morphological investigation into functions of the jaw symphysis in carnivorans. J Morphol 167:339\u2013375. https:\/\/doi.org\/10.1002\/jmor.1051670308","journal-title":"J Morphol"},{"key":"1733_CR68","doi-asserted-by":"publisher","first-page":"8366","DOI":"10.1038\/s41598-017-08658-8","volume":"7","author":"S Sengupta","year":"2017","unstructured":"Sengupta S, Ezcurra MD, Bandyopadhyay S (2017) A new horned and long-necked herbivorous stem-archosaur from the Middle Triassic of India. Sci Rep 7:8366. https:\/\/doi.org\/10.1038\/s41598-017-08658-8","journal-title":"Sci Rep"},{"key":"1733_CR69","first-page":"1","volume":"8","author":"PC Sereno","year":"2005","unstructured":"Sereno PC, McAllister S, Brusatte SL (2005) TaxonSearch: a relational database for suprageneric taxa and phylogenetic definitions. PhyloInformatics 8:1\u201321","journal-title":"PhyloInformatics"},{"key":"1733_CR70","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1046\/j.1096-3642.2002.00028.x","volume":"136","author":"BJ Small","year":"2002","unstructured":"Small BJ (2002) Cranial anatomy of Desmatosuchus haplocerus (Reptilia: Archosauria: Stagonolepididae). Zool J Linnean Soc 136:97\u2013111","journal-title":"Zool J Linnean Soc"},{"key":"1733_CR71","doi-asserted-by":"publisher","first-page":"997","DOI":"10.1111\/j.1475-4983.2010.00983.x","volume":"53","author":"MR Stocker","year":"2010","unstructured":"Stocker MR (2010) A new taxon of phytosaur (Archosauria: Pseudosuchia) from the Late Triassic (Norian) Sonsela Member (Chinle Formation) in Arizona, and a critical reevaluation of Leptosuchus Case, 1922. Palaeontology 53:997\u20131022","journal-title":"Palaeontology"},{"key":"1733_CR72","unstructured":"Stocker MR (2013) Contextualizing vertebrate faunal dynamics: new perspectives from the Triassic and Eocene of Western North America. Ph.D. dissertation, University of Texas at Austin, Austin, Texas, 317 pp"},{"key":"1733_CR73","doi-asserted-by":"publisher","first-page":"2674","DOI":"10.1016\/j.cub.2016.07.066","volume":"26","author":"MR Stocker","year":"2016","unstructured":"Stocker MR, Nesbitt SJ, Criswell KE, Parker WG, Witmer LM, Rowe TB, Ridgely R, Brown MA (2016) A dome-headed stem archosaur exemplifies convergence among dinosaurs and their distant relatives. Curr Biol 26:2674\u20132680. https:\/\/doi.org\/10.1016\/j.cub.2016.07.066","journal-title":"Curr Biol"},{"key":"1733_CR74","doi-asserted-by":"publisher","first-page":"20180922","DOI":"10.1098\/rsbl.2018.0922","volume":"15","author":"MR Stocker","year":"2019","unstructured":"Stocker MR, Nesbitt SJ, Kligman BT, Paluh DJ, Marsh AD, Blackburn DC, Parker WG (2019) The earliest equatorial record of frogs from the Late Triassic of Arizona. Biol Lett 15:20180922. https:\/\/doi.org\/10.1098\/rsbl.2018.0922","journal-title":"Biol Lett"},{"key":"1733_CR75","doi-asserted-by":"publisher","first-page":"571","DOI":"10.1080\/02724634.1996.10011340","volume":"16","author":"H-D Sues","year":"1996","unstructured":"Sues H-D (1996) A reptilian tooth with apparent venom canals from the Chinle Group (Upper Triassic) of Arizona. J Vertebr Paleontol 16:571\u2013572","journal-title":"J Vertebr Paleontol"},{"key":"1733_CR76","volume-title":"Triassic life on land\u2014the great transition","author":"H-D Sues","year":"2010","unstructured":"Sues H-D, Fraser NC (2010) Triassic life on land\u2014the great transition. Columbia University, New York"},{"key":"1733_CR77","doi-asserted-by":"publisher","first-page":"49","DOI":"10.1144\/SP379.13","volume":"379","author":"H-D Sues","year":"2013","unstructured":"Sues H-D, Desojo JB, Ezcurra MD (2013) Doswelliidae: a clade of unusual armoured archosauriforms from the Middle and Late Triassic. Geol Soc Lond, Spec Publ 379:49\u201358","journal-title":"Geol Soc Lond, Spec Publ"},{"key":"1733_CR78","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1017\/S0016756800046434","volume":"105","author":"AD Walker","year":"1968","unstructured":"Walker AD (1968) Protosuchus, Proterochampsa, and the origin of phytosaurs and crocodiles. Geol Mag 105:1\u201314","journal-title":"Geol Mag"},{"key":"1733_CR79","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1098\/rstb.1990.0185","volume":"330","author":"AD Walker","year":"1990","unstructured":"Walker AD (1990) A revision of Sphenosuchus acutus Haughton, a crocodylomorph reptile from the Elliot Formation (late Triassic or early Jurassic) of South Africa. Philos Trans R Soc B 330:1\u2013120","journal-title":"Philos Trans R Soc B"},{"key":"1733_CR80","doi-asserted-by":"publisher","first-page":"144","DOI":"10.1016\/j.cub.2016.10.043","volume":"27","author":"S Wang","year":"2017","unstructured":"Wang S, Stiegler J, Amiot R, Wang X, G-h D, Clark JM, Xu X (2017) Extreme ontogenetic changes in a ceratosaurian theropod. Curr Biol 27:144\u2013148. https:\/\/doi.org\/10.1016\/j.cub.2016.10.043","journal-title":"Curr Biol"},{"key":"1733_CR81","doi-asserted-by":"publisher","first-page":"1","DOI":"10.2307\/1006472","volume":"70","author":"RE Weems","year":"1980","unstructured":"Weems RE (1980) An unusual newly discovered archosaur from the Upper Triassic of Virginia, U.S.A. Trans Am Philos Soc 70:1\u201353","journal-title":"Trans Am Philos Soc"},{"key":"1733_CR82","doi-asserted-by":"publisher","first-page":"525","DOI":"10.1144\/SP379.7","volume":"379","author":"JC Weinbaum","year":"2013","unstructured":"Weinbaum JC (2013) Postcranial skeleton of Postosuchus kirkpatricki (Archosauria:Paracrocodylomorpha), from the Upper Triassic of the United States. Geochem Soc Spec Publ 379:525\u2013553","journal-title":"Geochem Soc Spec Publ"},{"key":"1733_CR83","doi-asserted-by":"publisher","first-page":"e1748042","DOI":"10.1080\/02724634.2019.1748042","volume":"39","author":"BM Wynd","year":"2020","unstructured":"Wynd BM, Nesbitt SJ, Stocker MR, Heckert AB (2020) A detailed description of Rugarhynchos sixmilensis gen. et comb. nov. (Archosauriformes, Proterochampsia) and cranial convergence in snout elongation across stem and crown archosaurs. J Vertebr Paleontol 39:e1748042","journal-title":"J Vertebr Paleontol"}],"container-title":["The Science of Nature"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00114-021-01733-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00114-021-01733-1\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00114-021-01733-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,8,24]],"date-time":"2021-08-24T12:16:04Z","timestamp":1629807364000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00114-021-01733-1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,2]]},"references-count":83,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2021,8]]}},"alternative-id":["1733"],"URL":"https:\/\/doi.org\/10.1007\/s00114-021-01733-1","relation":{},"ISSN":["0028-1042","1432-1904"],"issn-type":[{"value":"0028-1042","type":"print"},{"value":"1432-1904","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,7,2]]},"assertion":[{"value":"11 November 2020","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"21 March 2021","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"12 April 2021","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"2 July 2021","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare that they have no conflict of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of Interest"}},{"value":"The nomenclatural acts have been registered in ZooBank, the online\u00a0registration system for the International Code of Zoological Nomenclature. The ZooBank Life\u00a0Science Identifiers for the taxa in this publication are urn:lsid:zoobank.org:pub:F031EEF8-A8E2-45B9-A268-D65E80FF0F3B [publication], urn:lsid:zoobank.org:act:6D6053EF-BC5D-4878-8CE7-C399CDD9FC5E [<i>Syntomiprosopus<\/i>], urn:lsid:zoobank.org:act:17BBA292-D616-45CC-9541-A0E07845466A [<i>Syntomiprosopus sucherorum<\/i>].","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Nomenclature"}}],"article-number":"32"}}