Dinosaur tracks from the Frontier Formation, Montana: preservation, distribution and palaeoecological significance for the middle Cretaceous terrestrial ecosystems of North America

References

• Andrews HN, Pearsall CS. 1941. On the flora of the frontier formation of southwestern Wyoming. Annals of the Missouri Botanical Garden. 28(2):165–192.
   Google Scholar
• Arbour VM, Currie PJ. 2016. Systematics, phylogeny and palaeobiogeography of the ankylosaurid dinosaurs. Journal of Systematic Palaeontology. 14(5):385–444.
   Web of Science ®Google Scholar
• Arbour VM, Mallon JC. 2017. Unusual cranial and postcranial anatomy in the archetypal ankylosaur Ankylosaurus magniventris. Facets. 2(2):764–794.
   Google Scholar
• Arbour VM, Zanno LE, Gates T. 2016. Ankylosaurian dinosaur palaeoenvironmental associations were influenced by extirpation, sea-level fluctuation, and geodispersal. Palaeogeography, Palaeoclimatology, Palaeoecology. 449:289–299.
   Web of Science ®Google Scholar
• Avrahami HM, Gates TA, Heckert AB, Makovicky PJ, Zanno LE. 2018. A new microvertebrate assemblage from the mussentuchit member, cedar mountain formation: insights into the paleobiodiversity and paleobiogeography of early late cretaceous ecosystems in western North America. PeerJ. 6:e5883.
   PubMed Web of Science ®Google Scholar
• Botfalvai G, Prondvai E, Ősi A. 2021. Living alone or moving in herds? A holistic approach highlights complexity in the social lifestyle of Cretaceous ankylosaurs. Cretaceous Research. 118:104633.
   Web of Science ®Google Scholar
• Bravo-Cuevas VM, Rodríguez-de la Rosa R. 2014. Dinosaurs and other reptiles from the mesozoic of Mexico. Bloominghton: Indiana University Press. A summary of the mesozoic vertebrate tracks of Mexico; p. 181.
   Google Scholar
• Brownstein CD. 2018. The biogeography and ecology of the Cretaceous non-avian dinosaurs of Appalachia. Palaeontologia Electronica. 21(1):1–56.
   Web of Science ®Google Scholar
• Butler RJ, Upchurch P, Norman DB. 2008. The phylogeny of the ornithischian dinosaurs. Journal of Systematic Palaeontology. 6(1):1–40.
   Web of Science ®Google Scholar
• Carpenter K. 1984. Skeletal reconstruction and life restoration of Sauropelta (Ankylosauria: Nodosauridae) from the Cretaceous of North America. Can J Earth Sci. 21(12):1491–1498.
   Web of Science ®Google Scholar
• Carpenter K. 1992. Behavior of hadrosaurs as interpreted from footprints in the “Mesaverde” Group (Campanian) of Colorado, Utah, and Wyoming. Rocky Mountain Geology. 29(2):81–96.
   Google Scholar
• Carpenter K, Bartlett J, Bird J, Barrick R. 2008. Ankylosaurs from the Price River Quarries, Cedar Mountain Formation (Lower Cretaceous), east-central Utah. Journal of Vertebrate Paleontology. 28(4):1089–1101.
   Web of Science ®Google Scholar
• Carpenter K, Kirkland JI, Burge D, Bird J. 2001. Disarticulated skull of a new primitive ankylosaurid from the Lower Cretaceous of eastern Utah. In: Carpenter K, editor. The armored dinosaurs. Bloominghton: Indiana University Press, Indiana; p. 211–238.
   Google Scholar
• Carrano MT, Oreska MP, Lockwood R. 2016. Vertebrate paleontology of the Cloverly Formation (Lower Cretaceous), II: paleoecology. Journal of Vertebrate Paleontology. 36(2):e1071265.
   Web of Science ®Google Scholar
• Chin K, Gill BD. 1996. Dinosaurs, dung beetles, and conifers: participants in a Cretaceous food web. Palaios. 11:280–285.
   Web of Science ®Google Scholar
• Cilliers CD, Tucker RT, Crowley JL, Zanno LE. 2021. PeerJ. Corte Madera (CA): O`Relly. Age constraint for the Moreno Hill Formation (Zuni Basin) by CA-TIMS and LA-ICP-MS detrital zircon geochronology; p. 9.
   Google Scholar
• Cobban WA, Dyman TS, Porter KW. 2005. Paleontology and stratigraphy of upper Coniacian–middle Santonian ammonite zones and application to erosion surfaces and marine transgressive strata in Montana and Alberta. Cretaceous Research. 26(3):429–449.
   Web of Science ®Google Scholar
• Cobban WA, Reeside JJB. 1952. Frontier Formation, Wyoming and adjacent areas. Am Assoc Pet Geol Bull. 36(10):1913–1961.
   Web of Science ®Google Scholar
• Cobos A, Gasco F, Royo-Torres R, Lockley MG, Alcala L. 2016. Dinosaur Tracks: the Next Step. Bloominghton: Indiana Univeristy Press. Dinosaur tracks as “four-dimensional phenomena” reveal how different species moved; p. 244–256.
   Google Scholar
• Currie PJ. 1995. Ornithopod trackways from the Lower Cretaceous of Canada, in: vertebrate fossils and the evolution of scientific concepts: writing in tribute to Beverly Halstead. Amsterdam: Gordon and Breach Publisher; p. 431–443.
   Google Scholar
• DeCelles PG, Currie BS. 1996. Long-term sediment accumulation in the Middle Jurassic–early Eocene Cordilleran retroarc foreland-basin system. Geology. 24(7):591–594.
   Web of Science ®Google Scholar
• de Souza Carvalho I, Leonardi G. 2021. Fossil footprints as biosedimentary structures for paleoenvironmental interpretation: examples from Gondwana. Journal of South American Earth Sciences. 106:102936.
   Web of Science ®Google Scholar
• Díaz-Martínez I, Pereda-Suberbiola X, Pérez-Lorente F, Canudo JI. 2015. Ichnotaxonomic Review of Large Ornithopod Dinosaur Tracks: temporal and Geographic Implications. PLoS ONE. 10(2):e0115477.
   PubMed Web of Science ®Google Scholar
• Difley RL, Ekdale AA. 2002. Footprints of Utah’s last dinosaurs: track beds in the Upper Cretaceous (Maastrichtian) North Horn Formation of the Wasatch Plateau, central Utah. Palaios. 17(4):327–346.
   Google Scholar
• Dyman TS, Haley JC, Perry WJ. 1991. Redefinition of Frontier Formation-Beaverhead Group contact, Lima Peaks area, southwestern Montana and southeastern Idaho In: contributions to Late Cretaceous stratigraphy and paleontology, western Montana. U.S. Geological Survey Bulletin 1962:1–7.
   Google Scholar
• Dyman TS, Nichols DJ. 1988. Stratigraphy of mid cretaceous blackleaf and lower part of the frontier formations in parts of beaverhead and madison Counties, Montana. USGS Bull. 1773:1–27.
   Google Scholar
• Dyman TS, Tysdal RG. 1998. Stratigraphy and depositional environmentof nonmarine facies of Frontier Formation, eastern Pioneer Mountains, southwestern Montana. Mountain Geologist. 35:115–125.
   Google Scholar
• Dyman TS, Tysdal RG, Perry WJ, Nichols DJ, Obradovich JD. 2008. Stratigraphy and structural setting of Upper Cretaceous frontier formation, western Centennial Mountains, southwestern Montana and southeastern Idaho. Cretaceous Research. 29(2):237–248.
   Web of Science ®Google Scholar
• Eaton JG. 2004. New screen-washing approaches to biostratigraphy and paleoecology of nonmarine rocks, Cretaceous of Utah. Bulletin of Carnegie Museum of Natural History. 2004(36):21–30.
   Google Scholar
• Eberth DA. 2005. The Geology. In: Currie PJ, Koppelhus EB, editors. Dinosaur Provincial Park: a spectacular ancient ecosystem revealed. Bloominghton: Indiana University Press; p. 54–81.
   Google Scholar
• Everhart MJ, Ewell K. 2006. Shark-bitten dinosaur (Hadrosauridae) caudal vertebrae from the Niobrara Chalk (Upper Coniacian) of western Kansas. Transactions of the Kansas Academy of Science. 109(1):27–35.
   Google Scholar
• Falkingham PL, Turner ML, Gatesy SM. 2020. Constructing and testing hypotheses of dinosaur foot motions from fossil tracks using digitization and simulation. Palaeontology. 63(6):865–880.
   Web of Science ®Google Scholar
• Fanti F, Bell PR, Sissons RL. 2013. A diverse, high-latitude ichnofauna from the Late Cretaceous Wapiti Formation, Alberta, Canada. Cretaceous Research. 41:256–269.
   Web of Science ®Google Scholar
• Farke AA, Maxwell WD, Cifelli RL, Wedel MJ. 2014. A ceratopsian dinosaur from the Lower Cretaceous of western North America, and the biogeography of Neoceratopsia. PLOS one. 9(12):e112055.
   PubMed Web of Science ®Google Scholar
• Feldman HR, Fabijanic JM, Faulkner BL, Rudolph KW. 2014. Lithofacies, parasequence stacking, and depositional architecture of wave-to tide-dominated shorelines in the Frontier Formation, western Wyoming, USA. Journal of Sedimentary Research. 84(8):694–717.
   Web of Science ®Google Scholar
• Finn TM. 2019. Stratigraphic cross sections of the Niobrara Interval of the Upper Cretaceous Cody Shale in the Bighorn Basin, Wyoming and Montana. U.S. Geological Survey Scientific Investigations Map. 3370:19.
   Google Scholar
• Fiorillo AR, Contessi MI, Kobayashi YO, McCarthy PJ, Lockley MG, Lucas SG. 2014. Theropod tracks from the lower Cantwell Formation (Upper Cretaceous) of Denali National Park, Alaska, USA with comments on theropod diversity in an ancient, high-latitude terrestrial ecosystem. New Mexico Museum of Natural History and Science. 62:429–439.
   Google Scholar
• Fiorillo AR, Decker PL, LePain DL, Wartes M, McCarthy PJ. 2010. A probable neoceratopsian manus track from the Nanushuk Formation (Albian, northern Alaska). Journal of Iberian Geology. 36(2):165–174.
   Web of Science ®Google Scholar
• Fiorillo AR, Hasiotis ST, Kobayashi Y, Breithaupt BH, McCarthy PJ. 2011. Bird tracks from the Upper Cretaceous Cantwell Formation of Denali National Park, Alaska, USA: a new perspective on ancient northern polar vertebrate biodiversity. Journal of Systematic Palaeontology. 9(1):33–49.
   Web of Science ®Google Scholar
• Fiorillo AR, Hasiotis ST, Kobayashi Y, Tomsich CS. 2009. A pterosaur manus track from Denali National Park. Alaska Range, Alaska, United States. Palaios. 24(7):466–472.
   Google Scholar
• Fiorillo AR, Kobayashi Y, McCarthy PJ, Tanaka T, Tykoski RS, Lee YN, Takasaki R, Yoshida J. 2019. Dinosaur ichnology and sedimentology of the Chignik Formation (Upper Cretaceous), Aniakchak National Monument, southwestern Alaska; Further insights on habitat preferences of high-latitude hadrosaurs. Plos One. 14(10):e0223471.
   PubMed Web of Science ®Google Scholar
• Fiorillo AR, McCarthy PJ, Kobayashi Y, Tomsich CS, Tykoski RS, Lee YN, Tanaka T, Noto CR. 2018. An unusual association of hadrosaur and therizinosaur tracks within Late Cretaceous rocks of Denali National Park, Alaska. Sci Rep. 8(1):1–2.
   PubMedGoogle Scholar
• Foster JR, Lockley MG, Lucas SG. 2006. The vertebrate ichnological record of the Morrison Formation (Upper Jurassic, North America). New Mexico Museum of Natural History and Science Bullletin. 36:203–216.
   Google Scholar
• Fowler DW. 2017. Revised geochronology. Correlation, and Dinosaur Stratigraphic Ranges of the Santonian-Maastrichtian (Late Cretaceous) Formations of the Western Interior of North America. PLoS ONE. 12(11):e0188426.
   Google Scholar
• Freimuth WJ, Varricchio DJ. 2019. Insect trace fossils elucidate depositional environments and sedimentation at a dinosaur nesting site from the Cretaceous (Campanian) Two Medicine Formation of Montana. Palaeogeography, Palaeoclimatology, Palaeoecology. 534:109262.
   Web of Science ®Google Scholar
• Gangloff RA, May KC, Storer JE. 2004. An early Late Cretaceous dinosaur tracksite in central Yukon territory, Canada. Ichnos. 11(34):299–309.
   Google Scholar
• García-Ortiz E, Pérez-Lorente F. 2014. Palaeoecological inferences about dinosaur gregarious behaviour based on the study of tracksites from La Rioja area in the Cameros Basin (Lower Cretaceous, Spain). Journal of Iberian Geology. 40(1):113.
   Web of Science ®Google Scholar
• Gasca JM, Moreno-Azanza M, Bádenas B, Díaz-Martínez I, Castanera D, Canudo JI, Aurell M. 2017. Integrated overview of the vertebrate fossil record of the Ladruñán anticline (Spain): evidence of a Barremian alluvial-lacustrine system in NE Iberia frequented by dinosaurs. Palaeogeography, Palaeoclimatology, Palaeoecology. 472:192–202.
   Web of Science ®Google Scholar
• Gierlinski G, Lockley MG. 2013. First report of probable therizinosaur (cf. Macropodosaurus) tracks from North America, with notes on the neglected vertebrate ichnofauna of the Ferron Sandstone. In: AL T, MA L, editors. At the Top of the Grand Staircase. Bloominghton: Indiana University Press; p. 530–535.
   Google Scholar
• Haley JC, Perry WJ. 1991. The Red Butte conglomerate—A thrust-belt-derived conglomerate of the Beaverhead Group, southwestern Montana. In: U.S. Geological Survey Bulletin. p. 1945.
   Google Scholar
• Hamblin AH, Bilbey SA, Hall JE. 2000. Prehistoric animal tracks at red fleet state park, northeastern Utah. Geology of Utah’s Parks and Monuments: Utah Geological Association Publication. 28:569–578.
   Google Scholar
• Henderson D. 2003. Footprints, trackways, and Hip heights of bipedal dinosaurs—testing Hip height predictions with computer models. Ichnos. 10(2–4):99–114.
   Google Scholar
• Horner JR. 1984. The nesting behavior of dinosaurs. Scientific American. 250(4):130–137.
   Web of Science ®Google Scholar
• Horner JR. 1987. Ecologic and behavioral implications derived from a dinosaur nesting site. In: Czerkas SJ, editor. Dinosaurs Past and Present, Volume 2. Seattle. Seattle: University of Washington Press; p. 50–63.
   Google Scholar
• Hornung JJ, Reich M. 2014. Metatetrapous valdensis Nopcsa, 1923 and the presence of ankylosaur tracks (Dinosauria: Thyreophora) in the Berriasian (Early Cretaceous) of Northwestern Germany. Ichnos. 21(1):1–8.
   Web of Science ®Google Scholar
• Houck KJ, Lockley MG. 2006. Life in an active volcanic arc: petrology and sedimentology of dinosaur track beds in the Jindong Formation (Cretaceous), Gyeongsang Basin, South Korea. Cretaceous Research. 27(1):102–122.
   Web of Science ®Google Scholar
• Hunt AP, Lucas SG. 2003. A new hadrosaur track from the Upper Cretaceous Fruitland Formation of northwestern New Mexico: new Mexico geological society, guidebook. 54. 379–381.
   Google Scholar
• Hutsky AJ, Fielding CR, Hurd TJ, Clark CK. 2012. Sedimentology and stratigraphy of the Upper Cretaceous (Cenomanian) Frontier Formation, northeast Bighorn Basin, Wyoming, USA. The Mountain Geologist. 49:77–99.
   Google Scholar
• Irby GV, Albright III LB. 2002. Tail-drag marks and dinosaur footprints from the Upper Cretaceous Toreva Formation. Northeastern Arizona. Palaios. 17(5):516–521.
   Web of Science ®Google Scholar
• Jerzykiewicz T, Currie PJ, Fanti F, Lefeld J. 2021. Lithobiotopes of the Nemegt Gobi Basin1. Can J Earth Sci. 58(9):829–851.
   Web of Science ®Google Scholar
• Joyce WG, Lyson TR. 2015. A review of the fossil record of turtles of the clade Baenidae. Bulletin of the Peabody Museum of Natural History. 56(2):147–183.
   Web of Science ®Google Scholar
• Kappus EJ, Lucas SG, Langford RI. 2011. The Cerro de Cristo Rey Cretaceous dinosaur tracksites, Sunland Park, New Mexico, USA, and Chihuahua, Mexico. Fossil Record. 3:272–288.
   Google Scholar
• Kirkland JI, Cifelli RL, Britt BB, Burge DL, DeCourten FL, Eaton JG, Parrish JM, Gillette DD. 1999. Distribution of vertebrate faunas in the Cedar Mountain Formation, east-central Utah. Vertebrate Paleontology in Utah. 99(1):201.
   Google Scholar
• Knight WC. 1902. The petroleum fields of Wyoming. Engineering and Mining Journal. 73:720–723.
   Google Scholar
• Knowlton FH. 1917. A fossil flora from the Frontier Formation of southwestern Wyoming. United States Geological Survey Professional Paper. 108:71–93.
   Google Scholar
• Krumenacker LJ. 2019. Paleontological and chronostratigraphic correlations of the mid-Cretaceous Wayan-Vaughn depositional system of southwestern Montana and southeastern Idaho. Hist Biol. doi:10.1080/08912963.2019.1582035
   Web of Science ®Google Scholar
• Krumenacker LJ, Simon DJ, Scofield G, Varricchio DJ. 2016. Theropod dinosaurs from the Albian–Cenomanian Wayan Formation of eastern Idaho. Hist Biol. 29(2):170–186.
   Web of Science ®Google Scholar
• Lichtig AJ, Lucas SG. 2016. Cretaceous nonmarine turtle biostratigraphy and evolutionary events. Cretaceous Period: Biotic Diversity and Biogeography: Bulletin. 71:71–185.
   Google Scholar
• Lockley MG. 2014. Tracking Dinosaurs in a Tepee: rare traces of Cretaceous Tetrapods from Montana. New Mexico Museum of Natural History and Science Bulletin. 62:421–428.
   Google Scholar
• Lockley MG. 2018. A large assemblage of dinosaur tracks from a valley fill deposit in the Dakota Sandstone, central Utah: the Cretaceous fossil footprint database expands westward. New Mexico Museum of Natural History and Science Bulletin. 79:375–385.
   Google Scholar
• Lockley MG, Cart K, Martin J, Milner ARC. 2011. New theropod tracksites from the Upper Cretaceous “Mesaverde” Group, western Colorado: implications for ornithomimosaur track morphology. New Mexico Museum of Natural History and Science Bulletin. 3:321–329.
   Google Scholar
• Lockley MG, Foster J. 2003. Late Cretaceous mammal tracks from North America. Ichnos. 10(2–4):269–276.
   Google Scholar
• Lockley MG, Holbrook J, Kukihara R, Matsukawa M. 2006a. An ankylosaur-dominated dinosaur tracksite in the Cretaceous Dakota Group of Colorado: paleoenvironmental and sequence stratigraphic context. New Mexico Museum of Natural History and Science Bulletin. 35:95–104.
   Google Scholar
• Lockley MG, Hunt AP. 1995. Ceratopsid tracks and associated ichnofauna from the Laramie Formation (Upper Cretaceous: Maastrichtian) of Colorado. Journal of Vertebrate Paleontology. 15(3):592–614.
   Web of Science ®Google Scholar
• Lockley MG, Hunt AP. 1998. Dinosaur tracks: and other fossil footprints of the western United States. New York: Columbia Unviversity Press. p. 19.
   Google Scholar
• Lockley MG, Hunt A, Holbrook J, Matsukawa M, Meyer C. 1992. The dinosaur freeway: a preliminary report on the Cretaceous megatracksite, Dakota Group, Rocky Mountain Front Range, and High Plains, Colorado, Oklahoma and New Mexico. In: Flores RM, editor. Field Guidebook Mesozoic of the Western Interior SEPM 1992 Theme Meeting. Fort Collins: Colorado State University; p. 39–54.
   Google Scholar
• Lockley MG, Kim KS, Lim JD. 2021. Tetrapodosaurus trackways from the Cretaceous of Colorado and Canada: observations on variability in ankylosaurian gaits. New Mexico Museum of Natural History and Science Bulletin. 7(82):227–235.
   Google Scholar
• Lockley MG, Matsukawa M, Witt D. 2006. Giant theropod tracks from the Cretaceous Dakota group of Northeastern New Mexico. New Mexico Museum of Natural History and Science Bulletin. 35:83–87.
   Google Scholar
• Lockley MG, Nadon G, Currie PJ. 2004. A diverse dinosaur-bird footprint assemblage from the lance formation, upper cretaceous, eastern Wyoming: implications for ichnotaxonomy. Ichnos. 11(3–4):229–249.
   Google Scholar
• Lockley MG, Xing L, Lockwood JA, Pond S. 2014. A review of large Cretaceous ornithopod tracks, with special reference to their ichnotaxonomy. Biological Journal of the Linnean Society. 113(3):721–736.
   Web of Science ®Google Scholar
• Lockley MG, Young BH, Carpenter K. 1983. Hadrosaur locomotion and herding behavior: evidence from footprints in the Mesaverde Formation, Grand Mesa Coal Field, Colorado. The Mountain Geologist. 20:5–14.
   Google Scholar
• Lucas SG, Dalman SG, Sullivan RM. 2016. Cretaceous dinosaur footprints from Sierra County, New Mexico. New Mexico Museum of Natural History and Science Bulletin. 74:151–152.
   Google Scholar
• Lucas SG, Hunt AP. 2006. Dinosaur tracks from the Upper Cretaceous Menefee Formation, west-central New Mexico. Late Cretaceous Vertebrated from the Western Interior. New Mexico Museum of Natural History and Science Bulletin 35:79–81.
   Google Scholar
• Lucas SG, Sullivan RM, Jasinski SE, Ford TL. 2011. Hadrosaur footprints from the Upper Cretaceous Fruitland Formation, San Juan Basin, New Mexico, and the ichnotaxonomy of large ornithopod footprints. New Mexico Museum of Natural History Bulletin. 53:357–362.
   Google Scholar
• Lull RS. 1920. The Cretaceous armored dinosaur, Nodosaurus textilis Marsh. American Journal of Science. 1(2):97–126.
   Google Scholar
• Mallison H, Wings O. 2014. Photogrammetry in paleontology—a practical guide. Journal of Paleontological Techniques. 12(12):1–31.
   Google Scholar
• Mann JA. 1960. Geology of part of the Gravelly Range area, Montana. Billings Geological Giudebook 11th Annual Field Conference. Billings. p. 114–127.
   Google Scholar
• Manning PL, Ott C, Falkingham PL. 2008. A probable tyrannosaurid track from the Hell Creek Formation (Upper Cretaceous), Montana, United States. Palaios. 23(10):645–647.
   Web of Science ®Google Scholar
• Mannion PD, Upchurch P. 2011. A re-evaluation of the ‘mid-Cretaceous sauropod hiatus’ and the impact of uneven sampling of the fossil record on patterns of regional dinosaur extinction. Palaeogeography, Palaeoclimatology, Palaeoecology. 299(3–4):529–540.
   Web of Science ®Google Scholar
• Maples CG, Archer AW. 1989. The potential of Paleozoic nonmarine trace fossils for paleoecological interpretations. Palaeogeography, Palaeoclimatology, Palaeoecology. 73(3–4):185–195.
   Web of Science ®Google Scholar
• Marenco KN, Hagadorn JW. 2019. Big bedding planes: outcrop size and spatial heterogeneity influence trace fossil analyses. Palaeogeography, Palaeoclimatology, Palaeoecology. 513:14–24.
   Web of Science ®Google Scholar
• Marsh OC. 1889. Notice of gigantic horned Dinosauria from the Cretaceous. American Journal of Science. 224(224):173–176.
   Google Scholar
• Martin AJ, Varricchio DJ. 2011. Paleoecological utility of insect trace fossils in dinosaur nesting sites of the Two Medicine Formation (Campanian), Choteau, Montana. Hist Biol. 23(1):15–25.
   Web of Science ®Google Scholar
• Masters JA, 1952. The Frontier Formation of Wyoming: wyoming Geol. Assoc. Guide Book, 7th Ann. Field Conf., Southern Big Horn Basin; p. 58–62
   Google Scholar
• McCrea RT 2000. Vertebrate palaeoichnology of the Lower Cretaceous (lower Albian) Gates Formation of Alberta. Master dissertation. University of Saskatchewan, Saskatoon.
   Google Scholar
• McCrea RT, Buckley LG, Plint AG, Currie PJ, Haggart JW, Helm CW, Pemberton SG. 2014. A review of vertebrate track-bearing formations from the Mesozoic and earliest Cenozoic of western Canada with a description of a new theropod ichnospecies and reassignment of an avian ichnogenus. New Mexico Museum of Natural History and Science Bulletin. 62:5–93.
   Google Scholar
• McCrea RT, Currie PJ 1998. A preliminary report on dinosaur tracksites in the Lower Cretaceous (Albian) Gates Formation near Grande Cache, Alberta. Bulletin of the New Mexico Museum of Natural History and Science. 14: 155–162.
   Google Scholar
• McCrea RT, Lockley MG, Meyer C. 2001. Global distribution of purported ankylosaur track occurrences. In: Carpenter K, editor. The armored dinosaurs. Bloomington (Indianapolis): Indiana University Press; p. 414.
   Google Scholar
• McDonald AT, Gates TA, Zanno LE, Makovicky PJ. 2017. Anatomy, taphonomy, and phylogenetic implications of a new specimen of Eolambia caroljonesa (Dinosauria: ornithopoda) from the Cedar Mountain Formation, Utah, USA. PLoS One. 12(5):e0176896.
   PubMed Web of Science ®Google Scholar
• McDonald AT, Wolfe DG, Kirkland JI. 2010. A new basal hadrosauroid (Dinosauria: Ornithopoda) from the Turonian of New Mexico. Journal of Vertebrate Paleontology. 30:799–812.
   Web of Science ®Google Scholar
• Merewether EA, Cobban WA, Cavanaugh ET. 1979. Frontier Formation and equivalent rocks in eastern Wyoming. Mountain Geologist. 16:67–101.
   Google Scholar
• Milàn J, Bromley RG. 2006. True tracks, undertracks, and eroded tracks, experimental work with tetrapod tracks in laboratory and field. Palaeogeography, Palaeoclimatology, Palaeoecology. 231(3–4):253–264.
   Web of Science ®Google Scholar
• Milner AR, Vice GS, Harris JD, Lockley MG. 2006. Dinosaur tracks from the Upper Cretaceous Iron Springs Formation, Iron County, Utah. New Mexico Museum of Natural History and Science Bulletin. 35:105–113.
   Google Scholar
• Nadon GC. 1993. The association of anastomosed fluvial deposits and dinosaur tracks, eggs, and nests: implications for the interpretation of floodplain environments and a possible survival strategy for ornithopods. Palaios. 8:31–44.
   Web of Science ®Google Scholar
• Nakajima J, Kobayashi Y, Chinzorig T, Tanaka T, Takasaki R, Tsogtbaatar K, Currie PJ, Fiorillo AR. 2018. Dinosaur tracks at the Nemegt locality: paleobiological and paleoenvironmental implications. Palaeogeography, Palaeoclimatology, Palaeoecology. 494:147–159.
   Web of Science ®Google Scholar
• Nesbitt SJ, Denton RK, Loewen MA, Brusatte SL, Smith ND, Turner AH, Kirkland JI, McDonald AT, Wolfe DG. 2019. A mid-Cretaceous tyrannosauroid and the origin of North American end-Cretaceous dinosaur assemblages. Nature Ecology and Evolution. 3(6):892–899.
   PubMed Web of Science ®Google Scholar
• Nicosia U, Petti FM, Perugini G, Porchetti SDO, Sacchi E, Conti MA, Mariotti N, Zarattini A. 2007. Dinosaur tracks as paleogeographic constraints: new scenarios for the Cretaceous geography of the Periadriatic region. Ichnos. 14(1–2):69–90.
   Google Scholar
• Noè LF, Gómez–Pérez M, Rodríguez JV, Corrales–García A, Caranton–Mateus WG. 2020. Dinosaur footprints from the Lower Cretaceous, Batá Formation, Colombia (South America), and the possible interchange of large ornithopods between southern Laurasia and northern Gondwana. The Geology of Colombia. 2:375–401.
   Google Scholar
• Noffke N, Hagadorn J, Bartlett S. 2019. Microbial structures and dinosaur trackways from a Cretaceous coastal environment (Dakota Group, Colorado, USA). Journal of Sedimentary Research. 89(11):1096–1108.
   Web of Science ®Google Scholar
• Oreska MP, Carrano MT, Dzikiewicz KM. 2013. Vertebrate paleontology of the Cloverly Formation (Lower Cretaceous), I: faunal composition, biogeographic relationships, and sampling. Journal of Vertebrate Paleontology. 33(2):264–292.
   Web of Science ®Google Scholar
• Ortíz-Mendieta JA 2001. Dinosauricnitas Cretácico-tardías de El Aguaje, Michoacán, Región Suroccidental de México y sus implicaciones geológico-paleontológicas. Doctoral dissertation. Facultad de Ciencias, Universidad Nacional Autónoma de México.
   Google Scholar
• Panascí G, Varricchio DJ, Hirayama R. 2020. New occurrence of Neurankylus sp. (Testudines: Paracryptodiria: Baenidae) in the Upper Cretaceous Frontier Formation of South Western Montana (USA). Cretaceous Research 108:104318.
   Google Scholar
• Panascí G, Varricchio DJ, Wilson JP, Dyman T. 2021. Ichnology and sedimentology of the Coniacian non-marine Frontier Formation, western Centennial Mountains, southwestern Montana, USA. Hist Biol. 34(1):1–18.
   Web of Science ®Google Scholar
• Parker LR, Rowley JRL. 1989. Dinosaur footprints from a coal mine in east-central Utah, in: dinosaur tracks and traces. New York: Cambridge University Press; p. 361–366.
   Google Scholar
• Petti FM, Bernardi M, Todesco R, Avanzini M. 2011. Dinosaur footprints as ultimate evidence for a terrestrial environment in the late Sinemurian Trento carbonate platform. Palaios. 26(10):601–606.
   Web of Science ®Google Scholar
• Plint AG, Helm CW, Lockley MG. 2022. Crocodylian and dinosaur trace fossil assemblages from crevasse splay/levee and floodplain lake environments: middle Cenomanian Dunvegan Formation, northeast British Columbia, Canada. Hist Biol. 5:1–27.
   Google Scholar
• Riguetti F, Citton P, Apesteguía S, Zacarías GG, Pereda-Suberbiola X. 2021. New ankylosaurian trackways (cf. Tetrapodosaurus) from an Uppermost Cretaceous Level of the El Molino Formation of Bolivia. Cretaceous Research 124:104810.
   Google Scholar
• Roberts AE. 1972. Cretaceous and early tertiary depositional and tectonic history of the Livingston area, southwestern Montana. US Government Printing Office. 526C:1–120.
   Google Scholar
• Roberts LNR, Kirschbaum MA 1995. Paleogeography of the Late Cretaceous of the western interior of middle North America—Coal distribution and sediment accumulation: U.S. Geological Survey Professional Paper 1561.
   Google Scholar
• Rodriguez De La Rosa. 2001. Pterosaur tracks from the Late Cretaceous of northern Mexico: paleoecological and anatomical implications. Two Hundred Years of Pterosaurs. Strata. 11:85–86.
   Google Scholar
• Rodriguez de la Rosa RA. 2003. Pterosaur tracks from the latest Campanian Cerro del Pueblo Formation of southeastern Coahuila, Mexico. Geological Society, London, Special Publications. 217(1):275–282.
   Google Scholar
• Romilio A. 2020. An Instructional Guide to Visualising Dinosaur Tracks. Eons Press.
   Google Scholar
• Rosenblume JA, 2021. Evolution of the Early-Late Cretaceous foreland basin system in southwestern Montana based on U-Pb detrital zircon geochronology. Doctoral dissertation, The University of Iowa.
   Google Scholar
• Rosenblume JA, Finzel ES, Garber KL. 2018. Sedimentology and provenance of the Upper Cretaceous (Cenomanian to Santonian) Frontier Formation, southwest Montana and east‐central Idaho. Geological Society of America Abstracts with Programs 50.
   Google Scholar
• Rylaarsdam JR, Varban BL, Plint AG, Buckley LG, McCrea RT. 2006. Middle Turonian dinosaur paleoenvironments in the Upper Cretaceous Kaskapau Formation, northeast British Columbia. Can J Earth Sci. 43(6):631–652.
   Web of Science ®Google Scholar
• Seilacher A. 2007. Trace Fossil Analysis. Berlin: Springer-Verlag; p. 226.
   Google Scholar
• Sereno PC. 1997. The origin and evolution of dinosaurs. Annu Rev Earth Planet Sci. 25(1):435–489.
   Google Scholar
• Shibata M, Varricchio DJ. 2020. Horseshoe crab trace fossils from the Upper Cretaceous Two Medicine Formation of Montana, USA, and a brief review of the xiphosurid ichnological record. Journal of Paleontology. 94(5):887–905.
   Web of Science ®Google Scholar
• Simpson E, Fitzgerald MH, Hilbert-Wolf HHL, Alexsteullet K, Wizevich MC, Tindal S. 2011. Upper cretaceous dinosaur tracks from the upper and capping sandstone members of the wahweap formation, grand staricase-escalante national monument, Utah, USA. New Mexico Museum of Natural History and Science Bulletin. 53:380–385.
   Google Scholar
• Therrien F, Zelenitsky DK, Quinney A, Tanaka K. 2015. Dinosaur trackways from the Upper Cretaceous Oldman and Dinosaur Park formations (Belly River Group) of southern Alberta, Canada, reveal novel ichnofossil preservation style. Can J Earth Sci. 52(8):630–641.
   Web of Science ®Google Scholar
• Thulborn T. 1990. Dinosaur tracks. London: Chapman et Hall Press.
   Google Scholar
• Tillman RW, Almon WR. 1979. Diagenesis of Frontier Formation offshore bar sandstones Spearhead Ranch Field, Wyoming, in: aspects of Pore-lining Chlorites Diagenesis. SEPM Special Publication. 26:337–378.
   Google Scholar
• Tsukiji Y, Azuma Y, Shiraishi F, Shibata M, Noda Y. 2018. New ornithopod footprints from the Lower Cretaceous Kitadani Formation, Fukui, Japan: ichnotaxonomical implications. Cretaceous Research. 84:501–514.
   Web of Science ®Google Scholar
• Tucker RT, Zanno LE, Huang HQ, Makovicky PJ. 2020. A refined temporal framework for newly discovered fossil assemblages of the upper Cedar Mountain Formation (Mussentuchit Member), Mussentuchit Wash, Central Utah. Cretaceous Research. 110:104384.
   Web of Science ®Google Scholar
• Tysdal RG. 1991. Depositional Environments for Strata of Composite Section of Frontier Formation, Madison Range, Southwestern Montana. U.S. Geological Survey Bulletin. 1949:16.
   Google Scholar
• Tysdal RG, Dyman TS, Nichols DJ. 1989a. Correlation chart of Lower Cretaceous rocks, Madison Range to Lima Peaks area, southwestern Montana. U.S. Geological Survey Miscellaneous Field Studies Map. MF-2067:16.
   Google Scholar
• Tysdal RG, Dyman TS, Nichols DJ, Cobban WA. 1990. Correlation chart of Frontier Formation from Greenhorn Range, southwestern Montana, to Mount Everts in Yellowstone National Park, Wyoming: u.S. Geological Survey Miscellaneous Field Studies. 2116:16.
   Google Scholar
• Varricchio DJ, Horner JR. 1993. Hadrosaurid and lambeosaurid bone beds from the Upper Cretaceous Two Medicine Formation of Montana: taphonomic and biologic implications. Can J Earth Sci. 30(5):997–1006.
   Web of Science ®Google Scholar
• Varricchio DJ, Martin AJ, Katsura Y 2007. First trace and body fossil evidence of a burrowing, denning dinosaur. Proceedings of the Royal Society B: Biological Sciences. 274(1616):1361–1368.
   Google Scholar
• Vogt M, Stinnesbeck W, Zell P, Kober B, Kontny J, Herzer N, Huerta DF. 2016. Age and depositional environment of the “dinosaur graveyard” at Las Águilas, southern Coahuila, NE Mexico. Palaeogeography, Palaeoclimatology, Palaeoecology. 441:758–769.
   Web of Science ®Google Scholar
• White CD, Willis BJ, Dutton SP, Bhattacharya JP, Narayanan K. 2004. Sedimentology, statistics, and flow behavior for a tide-influenced deltaic sandstone, Frontier Formation, Wyoming, United States, in: integration of outcrop and modern analogs in reservoir modeling. AAPG Memoir. 80:129–152.
   Google Scholar
• Williamson TE. 2000. Review of Hadrosauridae (Dinosauria, Ornithischia) from the San Juan Basin, New Mexico: new Mexico Museum of Natural History and Science Bulletin. 17:191–213.
   Google Scholar
• Wilson JA. 2005. Integrating ichnofossil and body fossil records to estimate locomotor posture and spatiotemporal distribution of early sauropod dinosaurs: a stratocladistic approach. Paleobiology. 31(3):400–423.
   Web of Science ®Google Scholar
• Winn RD. 1991. Storm deposition in marine sand sheets; Wall Creek Member, Frontier Formation, Powder River basin, Wyoming. Journal of Sedimentary Research. 61(1):86–101.
   Google Scholar
• Wolberg DL, Hall JP, Bellis D. 1988. First record of dinosaur footprints from the Fruitland Formation, San Juan County, New Mexico. New Mexico Bureau of Mines and Mineral Resources. 122:33–34.
   Google Scholar
• Wolfe DG. 2006. Theropod dinosaur tracks from the Upper Cretaceous (Turonian) Moreno Hill Formation of New Mexico. New Mexico Museum of Natural History and Science Bulletin. 35:115–117.
   Google Scholar
• Wolfe DG, Kirkland JI, Lucas SG. 1998. Zuniceratops christopheri n. gen. & n. sp., a ceratopsian dinosaur from the Moreno Hill Formation (Cretaceous, Turonian) of west-central New Mexico. New Mexico Museum of Natural History and Science Bulletin. 14:303–317.
   Google Scholar
• Zanno LE, Tucker RT, Canoville A, Avrahami HM, Gates TA, Makovicky PJ. 2019. Diminutive fleet-footed tyrannosauroid narrows the 70-million-year gap in the North American fossil record. Communications Biology. 2(1):1–2.
   PubMedGoogle Scholar
• Zartman RE, Dyman TS, Tysdal RG, Pearson RC. 1995. U-Pb ages of volcanogenic zircon from porcellanite beds in the Vaughn Member of the mid-Cretaceous Blackleaf Formation, southwestern Montana. USGS Bull. 2113:1–15.
   Google Scholar