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Paleobios 37:1–56, November 12, 2020 Paleobios PaleoBios 37:1–56, November 12, 2020 PaleoBios OFFICIAL PUBLICATION OF THE UNIVERSITY OF CALIFORNIA MUSEUM OF PALEONTOLOGY Lagerpetidae ilesauridae errerasauridae early Theropoda Neotheropoda auropodomorpha ADAM D. MARSH & WILLIAM G. PARKER (2020). New dinosauromorph specimens from Petrified Forest National Park and a global biostrati- graphic review of Triassic dinosauromorph body fossils. Cover: Global from [freevectormaps.com] and silhouettes used from [phylopic.org]; see acknowledgements for full links. Citation Triassic dinosauromorph occurrences known from body fossils. Maps modified global biostratigraphic review of Triassic dinosauromorph body fossils. PaleoBios, 37. ucmp_paleobios_50859. : Marsh, A.D. and W.G. Parker. 2020. New dinosauromorph specimens from Petrified Forest National Park and a New dinosauromorph specimens from Petrified Forest National Park and a global biostratigraphic review of Triassic dinosauromorph body fossils ADAM D. MARSH* and WILLIAM G. PARKER Petrified Forest National Park,[email protected] Department of Science and Resource Management, 1 Park Road #2217, Petrified Forest National Park, AZ 86028 Dinosauromorph from four major col- lecting efforts since 1982, including the most recent paleontological inventory of new park lands acquired in 2011. Additionally, specimens an emphasis from Petrified on understanding Forest National the stepwise Park have acquisition been recovered of character traits along the dinosaurian lineage has helped identify previously collected describe and use National Park, bringing the total number of dinosauromorphspecimens specimens in museum presently collections. known from Here the we park briefly to 50, a 600% increaseapomorphies since the year to identify 2000. These 32 additional specimens dinosauromorph are all Norian in specimens found at Petrified Forest the proximal end of a tibia that represents the oldest age and come from the Blue Mesa Member,contextualize Sonsela these Member, specimens and Petrified with the Forest dinosauromorph Member of theassemblages Chinle Formation. from the These Norian include of New Mexico, and Texas, as well as the unambiguous dinosaur specimen from the Chinle Formation. We then Africa, and sauropodomorphUtah, and Colorado, ornithis- chian dinosaurs in Western North America.Carnian An and increase Norian in dinosauromorph sampling, combined assemblages with the from use of South apomorphies America, to identify collectedEurope. Despitespecimens, increased will continue sampling to improvewe still find the globalno evidence dinosauromorph for fossil record that can be used to answer questions on biochronology and the evolutionary history of the avian lineage. Keywords: Dinosauromorpha, Dinosauria, Theropoda, Chinle Formation, Triassic of dinosauromorphs are sensitive to the availability of th and early 21st centuries, the INTRODUCTION - For most of the late 20 reliably-identified body fossils (Irmis 2011). Thus, since beLate relatively Triassic depauperate, dinosauromorph outside record of the of notoriousthe Chinle mass For 1921 when Charles Camp first began, Parkerworking 2006 in the Late deathmation assemblage across the ofAmerican the neotheropod Southwest Coelophysis was thought bauri to hasTriassic been of a nearlythe Colorado constant Plateau, effort tostarting discover in the more Petrified fossils 1887 ofForest dinosaurs area ( Longand their and closestMurry 1995relatives. ) there , 1989 archosaurCope ( archosauromorphs,) from Ghost Ranch, phytosaurs, New Mexico and (pseudoColbert- efforts to locate dinosauromorph fossil-bearing localities suchian1947 archosaurs,). Among dinosaurs the numerous themselves specimens represented of non- Since the early 1980s, there have been four distinct in the Chinle Formation at Petrified Forest National Park 1998less than 5% of the Late Triassic tetrapod fossils collected (PEFO). The first was led by the University of California lowin Arizona, number Colorado, of dinosauromorph New Mexico, specimens and Utah in(Hunt the area,et al. Museum of Paleontology (UCMP) from 1981 to 1987 (Fig.- ). Regardless of the reasons behind1996, Therrienthe observed et al. 1). It culminated in the “Dawn of the Age of Dinosaurs in 2000, the American Southwest” field conference and sympo be it taphonomic, Whiteside effects ( Huntet al. et2011 al. , 2015 sium bulletin (LucasMurry and 1995 Hunt 1989). This synthesis of- Loughney et al. 2011) or geobiological exclusion Late Triassic paleontology of the entire western United (Irmis 2011 ), questions States (LongParker and 2006 ) was the most-cited publi related to the timing of the origin and diversification cation on Late Triassic vertebrate paleontology for nearly author for correspondence 20 years ( ). Kevin Padian and RobertParker ‘Rob’ Long visited PEFO in 1981 with Samuel Welles, Michael *Citation Parrish, Paul Olsen, John Bolt, and Will Downs ( - stratigraphic review of Triassic dinosauromorph body fossils. PaleoBios, 37. ucmp_paleobios_50859. Permalink: Marsh,: https://escholarship.org/uc/item/01w536hs A.D. and W.G. Parker. 2020. New dinosauromorph specimens from Petrified Forest National Park and a global bio Copyright . : Published under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC-BY-NC-SA) license 2 PALEOBIOS, VOLUME 37, NOVEMBER 2020 12 11 P 51 10 9 P 231 8 7 6 5 P 10 4 3 P 00 2 P 020 P P 211 1 0 1981 1982 1983 198 1985 1986 1987 1988 1989 1990 1991 1992 1993 199 1995 1996 1997 1998 1999 2000 2001 2002 2003 200 2005 2006 2007 2008 2009 2010 2011 2012 2013 201 2015 2016 2017 2018 2019 UCMP/ong MDM/unt PO/park PO/expansion Figure 1. National Park by year, including the four major collecting ef- forts mentioned in the text. Number of dinosauromorph specimens found at Petrified Forest 2006 - ) to relocate Camp’s PEFO sites. Padian’s work con Olson, an intern at the MDM, located the first purported tinued through 1983 (Long and Padian 1986) and Long 1996dinosaur locality in the Blue Mesa Member of the Chinle subsequently worked with various UCMP crews in the Formation at PFV 211 (Dinosaur Ridge); (Hunt et al. park through 1987. During this period UCMP field crews ) (Fig. 2). The MDM group also reported a partially discovered two of the most significantMurry 1995dinosaur localities- excavatedand Wrighttheropod 1999 specimen, from locality PFV 278 in the Norian-age Petrified Forest Member of the Chinle (Jeremiah’s Perch) from the Petrified Forest Member 1982,Formation which at produced PEFO (Long a partial and skeleton of a): coelophysid Anne Pres (HuntThe third effort, initiatedParker by William and Irmis Parker 2005 in 2001), which af- ton (an archaeologist)Padian 1986 found PFV 040 (Dinosaur Hill) in terwas the recently park hired returned a full-time and prepared paleontologist, at PEFO. concentrated thetheropod early theropod( Chindesaurus), and Bryan bryansmalli Small discovered is ongoing as the park paleontology program continues PFV 0201995 (Dinosaur Hollow) in 1984, the type-locality of on relocating historic Parkerlocalities 2002 and, finding new ones and Long and , 2006, The dis- Murry ( ) (Fig. 2). under Adam Marsh ( Revueltosaurus Parker and Clements The second dinosaur recovery effort at PEFO, led by 2004 thatParker Revueltosaurus and Irmis callenderi 2005) (Fig. 1). 1989 Adrian Hunt from the Mesalands Dinosaur Museum actuallycovery of a localitypseudosuchian PFV 297 archosaur (the and supported Quarry) the (MDM), ran from 1996 to 1999 and was referred to as clarified Hunt ( ) is the “Dawn of the Dinosaurs Project” (Hunt 1998). Tom MARSH & PARKER—NEW TRIASSIC DINOSAUROMORPHS AND GLOBAL BIOSTRATIGRAPHIC REVIEW 3 A B PV 302 PV 18 -0 PV 376 PV PV 332 PV PV 278 020 231 PV P 302 215 PV P 18 PV 92 P 376, P 51, P 53, 00 P 75, P 77 PV P 00, P 215, 56 PV PV P 020, P 071, 337 PV PV 211 75 P 231, P 332, 53 PV PV PV PV 217 P 278 122 51 77 PV PV 10 PV 262 288 5 miles PV P 35 35 PV P 089 071 PV P 10 089 -180 N P 122, P 211, P 217, Private or tate Trust and P 262, P 288, P 56 P 337 Petri�iedPark oad Forest National Park Administrative oundary PV Ma # ocality Figure 2. A Martz et al. B Stratigraphic position ( , modified from (2012) and geographic location ( ) of dinosauromorph fossils at Petrified ideaForest that National ornithischian Park. Radiometric and sauropodomorphages from Ramezani etbody al. (2011). fos- horizons in the park and established that the entire sils Parker et al. 2005, , Nesbitt et al. 2007 et al. 2011, , Atchley et al. 2013, Nordt et al. 2015 are absent in the Triassic of the American Southwest- Chinle Formation at PEFO is Norian in age (Ramezani sic( dinosaur paleontologyIrmis et al.in 2007athe area. Members of the). expansion of 2014 nearly 500 sq. km for the protection of pale).- Thus, theropods became the sole emphasis of Late Trias ontologicalIn 2004, the and United archaeological States Congress resources, authorized and the a fourth PEFO aPEFO Chindesaurus paleontology program discovered PFV 231 (the occurred as part of a systematic inventory of these new Giving Site; ,Fig. 2), a fossil-rich locality that included both dinosauromorph-collecting effort (2016–2018; Figs. 1, 2) -like animal and a coelophysid (Stocker et al. 2004 Parker and Irmis 2005). During this time, recoveredlands within numerous the increased theropod park andboundary. silesaurid PEFO femora crews dinosauromorph fossils were also found for the first time led by Charles Beightol, Adam Marsh, and Natalie Toth in the Sonsela Member at PFV 089 (the Bowman Site), at the highest stratigraphic level in the Petrified Forest
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