Bull Canyon Formation

Bull Canyon Formation
Stratigraphic range: Upper Triassic, late Norian
TypeGeological formation
Unit ofDockum Group
UnderliesRedonda Formation
OverliesTrujillo Formation
Thickness110 metres (360 ft)
Lithology
Primarymudstone
Othersandstone, siltstone, conglomerate
Location
Region New Mexico,
 Texas
Country United States
Type section
Named forBull Canyon (Guadalupe County, New Mexico)
Named byLucas & Hunt, 1998

The Bull Canyon Formation is a geological formation of Late Triassic (Norian) age in eastern New Mexico and the Texas Panhandle. It is one of several formations encompassed by the Dockum Group.

The Bull Canyon Formation preserves reptile fossils of the Revueltian "faunachron", and it is generally considered time-equivalent to the upper Cooper Canyon Formation, which crops out further south in west-central Texas.

History and geology

Triassic rocks in the Tucumcari Basin of east-central New Mexico have been prospected for fossils since the 1890s. The bulk of early fossil collecting in the formation was done by University of Michigan paleontologist E.C. Case (starting in the 1910s) and Yale paleontologist Joseph T. Gregory (starting in the 1940s). For much of the 20th century, all Late Triassic strata in New Mexico was assumed to belong to the Chinle Formation.[1] Kelley (1972) informally labelled a unit of fine-grained sediments in the upper part of the Triassic strata as the "upper shale member" of the Chinle Formation.[2][3]

Lucas & Hunt (1989) introduced the name "Bull Canyon Formation" for these exposures, referring to an area of badlands near Luciano Mesa in eastern Guadalupe County, New Mexico. At the Bull Canyon badlands (the type locality), the formation preserves 95 metres (312 ft) of sediment, about 80% of which is dark reddish mudstone. Yellowish-grey or greyish-red fine quartzarenite sandstone makes up about 16% of the layers, with rare siltstone and siltstone-pebble conglomerate.[4] Of special note is a thick brownish litharenite sandstone bed, the Saladito Point Bed, which is comparable to some sandstone beds in Petrified Forest National Park, Arizona. The Bull Canyon Formation reaches a maximum thickness of 110 metres (360 ft) in eastern New Mexico.[5] It lies above the Trujillo Formation, which has a much greater proportion of sandstone beds. In New Mexico, the Bull Canyon Formation is overlain by a similar but generally finer-grained geological unit, the Redonda Formation.[4][6][5][7]

Relationship to the Cooper Canyon Formation

For much of the 1990s and 2000s, the Bull Canyon Formation was conflated with another geological unit in the Dockum Group: the Cooper Canyon Formation. The Cooper Canyon Formation, which is most well-exposed in Garza County, Texas, was initially named as the "Cooper Member" by Chatterjee (1986),[8] before being raised to formation status by Lehman et al. (1992).[9] Both formations are thick geological units with a large proportion of reddish mudstone. Lehman et al. (1992) and Lehman (1994)[10] argued that the Bull Canyon Formation should be synonymized with the Cooper Canyon Formation. These authors suggested that the Boren Ranch Sandstone, which underlies the Cooper Canyon Formation in Garza County, is equivalent to the sandstone-rich Trujillo Formation in New Mexico and the Texas Panhandle. If this is the case, then the "Cooper Member" (and consequently Cooper Canyon Formation) would take priority as the first formal name applied to the mudstone-rich strata above the Trujillo Formation.[10]

Lucas and his colleagues pushed back, arguing that the "Cooper Member" was an invalid name: Chatterjee (1986)'s original stratotype was too thin to be comparable with other areas, and "Cooper" was preoccupied by Cooper Marl of South Carolina. They favored the Bull Canyon Formation as the first valid formal name for the mudstone-rich strata.[6] Carpenter (1997) reviewed both perspectives, noting various cases of noncompliance with the North American Stratigraphic Code. Carpenter eventually sided with Lehman's perspective.[11] Despite the disagreement between these two schools of thought, most studies agreed that the two formations, as generally perceived, were probably one-to-one equivalents.[3][4][9][6][10][11]

More extensive geological mapping in Texas by Martz (2008) disagreed with the idea that the Bull Canyon and Cooper Canyon formations were exact equivalents, nullifying the debate over priority. Martz notes that the sandstone beds of the Trujillo Formation are not equivalent to the Boren Ranch Sandstone, but rather to the middle part of the Cooper Canyon Formation. This would indicate that the lower-middle part of the Cooper Canyon Formation is older than the Bull Canyon Formation, and that only the upper Cooper Canyon Formation is equivalent.[7]

Paleobiota

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Several microvertebrate assemblages are known from the Bull Canyon Formation.[12][13][14][15]

Temnospondyls

Temnospondyls of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Apachesaurus A. gregorii Bull Canyon,
Revuelto Creek,
Barranca Creek,
Mesa Redonda,[1]
Skull, intercentra, other possible fragments[16][17] A small metoposaurid which appears to be better suited for terrestrial life than other metoposaurids.[16][17] Apachesaurus may simply represent juveniles of larger metoposaurids native to the American Southwest.[18]
Metoposauridae indet. Skull fragments[17] Large metoposaurid fragments of uncertain affinities, most common in conglomerates in the lower part of the formation. Possibly reworked from older strata.[17]

Synapsids

Synapsids of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Pseudotriconodon[19] P. chatterjeei[19] Bull Canyon[19] Teeth A "dromatheriid" cynodont.[19]

Reptiles

Avemetatarsalians

Avemetatarsalians of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Gojirasaurus[11] G. quayi[11] Revuelto Creek[11] Partial skeleton A very large "coelophysoid" theropod dinosaur.[20][11] One of the largest known Triassic theropods, though its validity as a distinct species is uncertain. Some (though not all) of its fossil material may belong to Shuvosaurus, and other remains resemble Coelophysis, albeit much larger and more robust.[21][22]
Neotheropoda indet. Bull Canyon Partial skeleton and fibula Specimens NMMNH P-4569 ("Comanchesaurus kuesi" or "Herrerasaurid B"[23]) and NMMNH P-4563, belonging to large early neotheropods similar to Gojirasaurus.[21][22][24]
Saurischia indet. Bull Canyon,
Revuelto Creek,
Barranca Creek
Teeth,[12] partial skeletons including vertebrae and hindlimb material Various fragmentary fossils in the Bull Canyon Formation have been referred to specific saurischian dinosaur taxa (Coelophysis,[12] Chindesaurus,[16] herrerasaurids,[25][23][17] "prosauropods",[16] etc.). These referrals are very tenuous and often contradictory.[21] Some purported Bull Canyon dinosaur fossils, such as specimen NMMNH P-17375 ("Cryptoraptor lockleyi") are difficult to distinguish from Shuvosaurus.[21]

Phytosaurs

Phytosaurs of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Machaeroprosopus M. andersoni "near Santa Rosa" (Bull Canyon?)[17] At least one skull, possibly other fossils Sometimes known as Pseudopalatus andersoni.[17] A 2013 study established that all phytosaur species previously classified as "Pseudopalatus" should rather be called Machaeroprosopus.[26] The holotype of M. andersoni was probably collected from the Bull Canyon Formation. A few other phytosaur fossils may also belong to the species, though detailed investigation has not been conducted. One putative specimen preserves stomach content of Vancleavea vertebrae and smaller phytosaur hip fragments.[17]
M. mccauleyi Bull Canyon,
Revuelto Creek,
Barranca Creek,
Cosner Ranch,[1]
Skulls and postcrania A brachyrostral (thick-snouted) mystriosuchin phytosaur. American phytosaurs are prone to significant taxonomic controversy, and this holds true for fossils from the Bull Canyon Formation. At various times, "Rutiodon" gregorii,[27][20] "Nicrosaurus" gregorii,[28] "Arribasuchus" buceros,[16] Pseudopalatus andersoni[17] and Pseudopalatus mccauleyi[29] have all been proposed as names for the most common Bull Canyon phytosaur species, a brachyrostral form. Many phytosaur fossils from the Bull Canyon Formation are indeterminate to the genus or species level.[16][17]
M. pristinus Bull Canyon Skulls and postcrania An uncommon dolichorostral (slender-snouted) mystriosuchin phytosaur, previously known as Pseudopalatus pristinus.[25][16][17] One specimen preserves stomach content of "Apachesaurus" vertebrae.[17]

Other pseudosuchians

Pseudosuchians of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Aetosaurus A. arcuatus L-501[30] Osteoderms[30] A small and rare aetosaurine aetosaur.[30] The referral of these fossils to Aetosaurus is questionable, as they show few diagnostic features.[31]
"Sphenosuchidae" indet. Barranca Creek Partial skeleton and skull fragments[32] An unnamed "sphenosuchian"-grade crocodylomorph similar to Hesperosuchus.[16][32] Indeterminate "sphenosuchian" fragments are common throughout the formation.[17]
Paratypothorax P. sp. Bull Canyon,
Revuelto Creek,
Cosner Ranch[1]
Osteoderms[33][16][1] A rare paratypothoracin aetosaur.
Postosuchus P. kirkpatricki Barranca Creek[16] Hip, vertebrae, and hindlimbs[16][17] A large rauisuchid. Indeterminate rauisuchid fossils are common throughout the formation, including teeth, vertebrae, and other postcranial fragments.[16][17]
Revueltosaurus[34] R. callenderi[34] Revuelto Creek Teeth,[34] partial skeleton[35] A small armored aetosauriform,[36] previously misidentified as an ornithischian dinosaur based on its similar teeth.[34][16][23][17]
Rioarribasuchus R. chamaensis Revuelto Creek[16] Paramedian osteoderms and isolated spikes A paratypothoracin aetosaur. Also known as Heliocanthus,[37] and previously considered a species of Desmatosuchus.[27][20][16][17][38]
Shuvosaurus S. inexpectatus Bull Canyon,
Revuelto Creek,
Barranca Creek
Premaxilla fragment,[20] postcrania[16][17] A common shuvosaurid poposauroid with a bipedal stance and a toothless, beaked skull. Fossils of this species are frequently confused with those of dinosaurs[21] and Poposaurus.[20][16][25][17] Many postcranial fossils were previously described as a new genus, "Chatterjeea",[16] until it was recognized that Shuvosaurus and "Chatterjeea" were synonyms.[17][21]
Typothorax T. coccinarum Bull Canyon,
Revuelto Creek,
Barranca Creek
Complete skeletons, osteoderms A large typothoracine aetosaur. One of the most abundant reptiles in the formation, known from multiple complete skeletons.[39][16][17][40]

Other reptiles

Other reptiles of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Chinlechelys C. tenertesta Revuelto Creek Partial skeleton An early turtle,[41][42] sometimes regarded as a species of Proganochelys.[43]
Lucianosaurus[44] L. wildi[44] Luciano Mesa Teeth Teeth of a herbivorous archosauriform of uncertain affinities,[35][21] initially described as a "fabrosaurid" ornithischian.[44][17]
Otischalkia O. elderae Revuelto Creek[45] Humerus fragments[45] A robust archosauromorph. Initially regarded as a late-surviving rhynchosaur,[45] but more likely an indeterminate malerisaurine azendohsaurid.[46]
Squamata? indet. Revuelto Creek,
Luciano Mesa
Jaw fragments Pleurodont jaw fragments, presumably from lepidosaurs or kuehneosaurids.[17]
Vancleavea[16] V. campi Vertebrae,[16] osteoderms, limb material[17] An armored semiaquatic archosauriform. Some vertebrae are preserved as gut contents in a phytosaur skeleton.[17]

Fish

Scales, coprolites, and other fragmentary fish fossils are common in the Bull Canyon and Revuelto Creek areas. Most of these likely belong to actinopterygians.[17][15]

Fish of the Bull Canyon Formation
Genus / Taxon Species Locality Material Notes Images
Arganodontidae? indet. Revuelto Creek Skull fragments Indeterminate lungfish similar to Arganodus.[17]
"Colobodontidae"? indet. Revuelto Creek Tooth plates "Phyllodont" fish teeth, traditionally referred to colobodontid or perleidid perleidiforms,[17] but more likely belonging to other unrelated fish such as coelacanths.[14]
Quayia[47] Q. zideki[47] Revuelto Creek[17] Skull material, basisphenoid fragments, scales[47] A coelacanth, almost as large as living Latimeria.
Redfieldiidae indet. Bull Canyon,
Revuelto Creek
Isolated scales and scaly body fragments[25][17] A redfieldiiform.
Reticulodus[48] R. synergus[48] Bull Canyon,[48]
Mesa Redonda[49]
Teeth A hybodont shark with durophagous (crushing) dentition.[48][49]
Semionotus S. cf. S. brauni Bull Canyon,
Revuelto Creek
Scaly body fragments[25][17] A robust semionotiform.
Tanaocrossus? T.? kalliokoski Skull and skeletal material,[25][17] including three-dimensional fossils A slender "palaeonisciform".

Other fossils

The Bull Canyon Formation preserves a rather diverse fauna of freshwater mollusks. Unionid bivalves (freshwater mussels) are locally abundant, primarily Unio (U. arizonensis and at least six unnamed species) and Antediplodon (A. dockumensis and one unnamed species). A hydrobiid snail, Triasamnicola pilsbryi, is also common.[50][17] Ostracods and coiled Spirorbis-like structures (probably tiny snail shells) round out the invertebrate body fossils known from the formation.[1][17]

Trackways of both vertebrates and invertebrates are known to occur in the Bull Canyon Formation. Narrow Acripes tracks were probably emplaced by notostracan crustaceans (tadpole shrimp) crawling in shallow temporary pools. A vertebrate ichnotaxon, Barrancapus cresapi, was named for vertebrate footprints found near Barranca Creek.[1][51]

A few plant fossils have been found in the formation, including charophyte green algae, bennettitalean leaves (Zamites powellii), large horsetail stems (Neocalamites sp.), and foliage of an enigmatic shrubby plant (Sanmiguelia sp.). Root casts and fossil wood are not uncommon, sometimes showing signs of fungus damage.[1][17]

See also

References

  1. ^ a b c d e f g h Hunt, Adrian P. (1997). "E.C. Case, J.T. Gregory, and early exploration for fossil vertebrates in the Bull Canyon Formation (Upper Triassic) of Eastern New Mexico". New Mexico Museum of Natural History and Science Bulletin. 11: 15–24.
  2. ^ Kelley, Vincent C. (1972). Kelley, V. C.; Trauger, F. D. (eds.). "Triassic rocks of the Santa Rosa country" (PDF). New Mexico Geological Society 23rd Annual Fall Field Conference Guidebook. New Mexico Geological Society: 84–90. doi:10.56577/FFC-23.
  3. ^ a b Lucas, Spencer G.; Hunt, Adrian P.; Morales, Michael (1985). "Stratigraphic nomenclature and correlation of Triassic rocks of east-central New Mexico--A preliminary report" (PDF). New Mexico Geological Society 36th Annual Fall Field Conference Guidebook. New Mexico Geological Society: 171–184. doi:10.56577/FFC-36.171.
  4. ^ a b c Lucas, Spencer G.; Hunt, Adrian P. (1989). Lucas, Spencer G.; Hunt, Adrian P. (eds.). "Revised Triassic stratigraphy in the Tucumcari Basin, east-central New Mexico". Dawn of the Age of Dinosaurs in the American Southwest. New Mexico Museum of Natural History: 150–170.
  5. ^ a b Lucas, Spencer G.; Heckert, Andrew B.; Hunt, Adrian P. (2001). "Triassic stratigraphy, biostratigraphy and correlation in east-central New Mexico" (PDF). New Mexico Geological Society 52nd Annual Fall Field Conference Guidebook. New Mexico Geological Society: 85–102. doi:10.56577/FFC-52.85. ISBN 978-1-58546-087-8.
  6. ^ a b c Lucas, Spencer G.; Anderson, Orin J.; Hunt, Adrian P. (1994). "Triassic stratigraphy and correlations, southern High Plains of New Mexico—Texas" (PDF). New Mexico Bureau of Mines & Mineral Resources Bulletin. 150: 105–126.
  7. ^ a b Martz, J. W. (2008). Lithostratigraphy, chemostratigraphy, and vertebrate biostratigraphy of the Dockum Group (Upper Triassic), of southern Garza County, West Texas (Unpublished PhD thesis). Texas Tech University. Retrieved 16 November 2021.
  8. ^ Chatterjee, Sankar; Carpenter, Kenneth (1986). "The Late Triassic Dockum vertebrates: their stratigraphic and paleobiogeographic significance". In Padian, Kevin (ed.). The Beginning of the Age of Dinosaurs: Faunal change across the Triassic-Jurassic boundary. New York: Cambridge University Press. pp. 139–150. ISBN 0521303281.
  9. ^ a b Lehman, Thomas; Chatterjee, Sankar; Schnable, John (1992). "The Cooper Canyon Formation (Late Triassic) of western Texas". Texas Journal of Science. 44: 349–355.
  10. ^ a b c Lehman, Thomas M. (1994). "The saga of the Dockum Group and the case of the Texas/New Mexico boundary fault" (PDF). New Mexico Bureau of Mines & Mineral Resources Bulletin. 150: 37–51.
  11. ^ a b c d e f Carpenter, Kenneth (1997-08-13). "A Giant Coelophysoid (Ceratosauria) Theropod from the Upper Triassic of New Mexico, USA". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 205 (2): 189–208. doi:10.1127/njgpa/205/1997/189. ISSN 0077-7749.
  12. ^ a b c Lucas, Spencer G.; Oakes, Wayne; Froehlich, Jeffery W. (1985). "Triassic microvertebrate locality, Chinle Formation, east-central New Mexico" (PDF). New Mexico Geological Society 36th Annual Fall Field Conference Guidebook. New Mexico Geological Society: 205–212. doi:10.56577/FFC-36.205.
  13. ^ Hunt, Adrian P.; Lucas, Spencer G. (1993). "Late Triassic microvertebrate localities in New Mexico (USA): implications for paleoecology". New Mexico Museum of Natural History and Science Bulletin. 3: 187–192.
  14. ^ a b Heckert, Andrew B. (2004). "Upper Triassic microvertebrates from the lower Chinle Group: Introduction, methods, and previous studies". New Mexico Museum of Natural History and Science Bulletin. 27: 3–11.
  15. ^ a b Heckert, Andrew B.; Lucas, Spencer G. (2006). "Micro- and small vertebrate biostratigraphy and biochronology of the Upper Triassic Chinle Group, southwestern USA". New Mexico Museum of Natural History and Science Bulletin. 37: 94–104.
  16. ^ a b c d e f g h i j k l m n o p q r s t u Long, Robert A.; Murry, Phillip 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.
  17. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai Hunt, Adrian P. (2001). "The vertebrate fauna, biostratigraphy and biochronology of the type Revultian land vertebrate faunachron, Bull Canyon Formation (Upper Triassic), east-central New Mexico" (PDF). New Mexico Geological Society Guidebook, 52nd Field Conference, Geology of the Llano Estacado. New Mexico Geological Society: 123–151. doi:10.56577/FFC-52.123. ISBN 978-1-58546-087-8.
  18. ^ Gee, Bryan M.; Parker, William G. (2020-02-07). "Morphological and histological description of small metoposaurids from Petrified Forest National Park, AZ, USA and the taxonomy of Apachesaurus". Historical Biology. 32 (2): 203–233. Bibcode:2020HBio...32..203G. doi:10.1080/08912963.2018.1480616. ISSN 0891-2963.
  19. ^ a b c d Lucas, Spencer G.; Oakes, Wayne (1988). "A Late Triassic cynodont from the American South-West" (PDF). Palaeontology. 31 (2): 445–449.
  20. ^ a b c d e Parrish, Michael; Carpenter, Kenneth (1986). "A new vertebrate fauna from the Dockum Formation (Late Triassic) of eastern New Mexico". In Padian, Kevin (ed.). The Beginning of the Age of Dinosaurs. New York: Cambridge University Press. pp. 151–160. ISBN 0521303281.
  21. ^ a b c d e f g Nesbitt, Sterling J.; Irmis, Randall B.; Parker, William G. (June 2007). "A critical re-evaluation of the Late Triassic dinosaur taxa of North America" (PDF). Journal of Systematic Palaeontology. 5 (2): 209–243. Bibcode:2007JSPal...5..209N. doi:10.1017/S1477201907002040. S2CID 28782207.
  22. ^ a b Griffin, Christopher T. (September 2019). "Large neotheropods from the Upper Triassic of North America and the early evolution of large theropod body sizes". Journal of Paleontology. 93 (5): 1010–1030. Bibcode:2019JPal...93.1010G. doi:10.1017/jpa.2019.13. ISSN 0022-3360.
  23. ^ a b c Hunt, Adrian P.; Lucas, Spencer G.; Heckert, Andrew B.; Sullivan, Robert M.; Lockley, Martin G. (1998). "Late Triassic dinosaurs from the western United States" (PDF). Geobios. 31 (4): 511–531. Bibcode:1998Geobi..31..511H. doi:10.1016/S0016-6995(98)80123-X.
  24. ^ Marsh, Adam D.; Parker, William G. (2020-11-12). "New dinosauromorph specimens from Petrified Forest National Park and a global biostratigraphic review of Triassic dinosauromorph body fossils" (PDF). PaleoBios. 37: 1–56. doi:10.5070/p9371050859. ISSN 2373-8189.
  25. ^ a b c d e f Hunt, Adrian P.; Lucas, Spencer G. (1993). "Triassic vertebrate paleontology and biochronology of New Mexico". New Mexico Museum of Natural History and Science Bulletin. 2: 49–60.
  26. ^ Parker, William G.; Hungerbühler, Axel; Martz, Jeffrey W. (2012). "The taxonomic status of the phytosaurs (Archosauriformes) Machaeroprosopus and Pseudopalatus from the Late Triassic of the western United States". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 103 (3–4): 265–268. Bibcode:2012EESTR.103..265P. doi:10.1017/S1755691013000339. ISSN 1755-6910.
  27. ^ a b Carpenter, Kenneth; Parrish, Michael (1985). "Late Triassic Vertebrates from Revuelto Creek, Quay County, New Mexico" (PDF). New Mexico Geological Society Guidebook, 36th Field Conference, Santa Rosa: 197–198.
  28. ^ Lucas, Spencer G.; Hunt, Adrian P.; Bennett, Christopher (1985). "Triassic vertebrates from east-central New Mexico in the Yale Peabody Museum" (PDF). New Mexico Geological Society 36th Annual Fall Field Conference Guidebook. New Mexico Geological Society: 199–203. doi:10.56577/FFC-36.199.
  29. ^ Hunt, Adrian P.; Lucas, Spencer G.; Spielmann, Justin A. (2006). "Sexual dimorphism in a large brachyrostral phytosaur (Archosauria: Crurotarsi) from the Late Triassic of western North America". New Mexico Museum of Natural History and Science Bulletin. 37: 563–567.
  30. ^ a b c Heckert, Andrew B.; Lucas, Spencer G. (1998). "First occurrence of Aetosaurus (Reptilia: Archosauria) in the Upper Triassic Chinle Group (USA) and its biochronological significance". Neues Jahrbuch für Geologie und Paläontologie - Monatshefte. 1998 (10): 604–612. doi:10.1127/njgpm/1998/1998/604.
  31. ^ Parker, William G. (2016-01-21). "Revised phylogenetic analysis of the Aetosauria (Archosauria: Pseudosuchia); assessing the effects of incongruent morphological character sets". PeerJ. 4: e1583. doi:10.7717/peerj.1583. ISSN 2167-8359. PMC 4727975.
  32. ^ a b Hunt, Adrian P.; Spielmann, Justin A.; Lucas, Spencer G. (2006). "A sphenosuchian (Archosauria, Crocodylomorpha) with a partial pelvis from the Upper Triassic Bull Canyon Formation (Norian: Revueltian), East-Central, New Mexico". New Mexico Museum of Natural History and Science Bulletin. 37: 571–574.
  33. ^ Hunt, Adrian P.; Lucas, Spencer G. (1992). "The first occurrence of the aetosaur Paratypothorax andressi (Reptilia, Aetosauria) in the western United States and its biochronological significance". Paläontologische Zeitschrift. 66 (1–2): 147–157. Bibcode:1992PalZ...66..147H. doi:10.1007/BF02989485. ISSN 0031-0220.
  34. ^ a b c d Hunt, Adrian P. (1989). Lucas, Spencer G.; Hunt, Adrian P. (eds.). "A new ?ornithischian dinosaur from the Bull Canyon Formation (Upper Triassic) of east-central New Mexico". Dawn of the Age of Dinosaurs in the American Southwest. New Mexico Museum of Natural History: 355–388.
  35. ^ a b Hunt, Adrian P.; Lucas, Spencer G.; Spielmann, Justin A. (2005). "The postcranial skeleton of Revueltosaurus callenderi (Archosauria: Crurotarsi) from the Upper Triassic of Arizona and New Mexico, USA". New Mexico Museum of Natural History and Science Bulletin. 29: 66–75.
  36. ^ Parker, William G.; Nesbitt, Sterling J.; Irmis, Randall B.; Martz, Jeffrey W.; Marsh, Adam D.; Brown, Matthew A.; Stocker, Michelle R.; Werning, Sarah (2022). "Osteology and relationships of Revueltosaurus callenderi (Archosauria: Suchia) from the Upper Triassic (Norian) Chinle Formation of Petrified Forest National Park, Arizona, United States". The Anatomical Record. 305 (10): 2353–2414. doi:10.1002/ar.24757. ISSN 1932-8486. PMC 9544919. PMID 34585850.
  37. '^ Parker, W. G. (2007). "Reassessment of the aetosaur Desmatosuchus' chamaensis with a reanalysis of the phylogeny of the Aetosauria (Archosauria:Pseudosuchia)" (PDF). Journal of Systematic Palaeontology. 5 (1): 41–68. Bibcode:2007JSPal...5...41P. doi:10.1017/S1477201906001994. S2CID 85826683.
  38. ^ Zeigler, Kate E.; Heckert, Andrew B.; Lucas, Spencer G. (2002). "A new species of Desmatosuchus (Archosauria: Aetosauria) from the Upper Triassic of the Chama Basin, north-central New Mexico". New Mexico Museum of Natural History and Science Bulletin. 21: 215–219.
  39. ^ Hunt, Adrian P.; Lucas, Spencer G.; Reser, Peter K. (1993). "A complete skeleton of the stagonolepidid Typothorax coccinarum from the Upper Triassic Bull Canyon Formation of East-Central New Mexico, USA". New Mexico Museum of Natural History and Science Bulletin. 3: 209–212.
  40. ^ Heckert, A.B.; Lucas, S.G.; Rinehart, L.F.; Celesky, M.D.; Spielmann, J.A.; Hunt, A.P. (2010). "Articulated skeletons of the aetosaur Typothorax coccinarum Cope (Archosauria: Stagonolepididae) from the Upper Triassic Bull Canyon Formation (Revueltian: early-mid Norian), eastern New Mexico, USA". Journal of Vertebrate Paleontology. 30 (3): 619–642. Bibcode:2010JVPal..30..619H. doi:10.1080/02724631003763524. S2CID 140536594.
  41. ^ Joyce, W.G.; Lucas, S.G.; Scheyer, T.M.; Heckert, A.B.; Hunt, A.P. (2009). "A thin-shelled reptile from the Late Triassic of North America and the origin of the turtle shell". Proceedings of the Royal Society B. 276 (1656): 507–513. doi:10.1098/rspb.2008.1196. ISSN 1471-2954. JSTOR 30244885. PMC 2664348. PMID 18842543.
  42. ^ Lichtig, A. J.; Lucas, S. G. (2021). "Chinlechelys from the Upper Triassic of New Mexico, USA, and the origin of turtles". Palaeontologia Electronica. 24 (1): Article number 24.1.a13. doi:10.26879/886.
  43. ^ Joyce, Walter G. (2017). "A Review of the Fossil Record of Basal Mesozoic Turtles" (PDF). Bulletin of the Peabody Museum of Natural History. 58 (1): 65–113. doi:10.3374/014.058.0105. ISSN 0079-032X.
  44. ^ a b c Hunt, A.P. and Lucas, S.G. (1994). Ornithischian dinosaurs from the Upper Triassic of the United States. In: Fraser, N.C. and Sues, H.-D. (eds), In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods. Cambridge University Press, pp. 227-241.
  45. ^ a b c Justin A. Spielmann; Spencer G. Lucas & Adrian P. Hunt (2013). "The first Norian (Revueltian) rhynchosaur: Bull Canyon Formation, New Mexico, U.S.A." New Mexico Museum of Natural History and Science Bulletin. 61: 562–566.
  46. ^ Nesbitt, Sterling J.; Stocker, Michelle R.; Ezcurra, Martín D.; Fraser, Nicholas C.; Heckert, Andrew B.; Parker, William G.; Mueller, Bill; Sengupta, Saradee; Bandyopadhyay, Saswati; Pritchard, Adam C.; Marsh, Adam D. (2022). Field, Daniel (ed.). "Widespread azendohsaurids (Archosauromorpha, Allokotosauria) from the Late Triassic of western USA and India". Papers in Palaeontology. 8 (1). Bibcode:2022PPal....8E1413N. doi:10.1002/spp2.1413. ISSN 2056-2799.
  47. ^ a b c Hunt, Adrian P. (1997). "A new coelacanth (Osteichthyes:Actinistia) from the continental Upper Triassic of New Mexico". New Mexico Museum of Natural History and Science Bulletin. 11: 25–27.
  48. ^ a b c d Murry, Phillip A.; Kirby, Randy E. (2002). "A new hybodont shark from the Chinle and Bull Canyon formations, Arizona, Utah, and New Mexico". New Mexico Museum of Natural History and Science Bulletin. 21: 87–106.
  49. ^ a b Voris, Jared T.; Heckert, Andrew B. (2017-07-04). "Ontogenetic heterodonty in Reticulodus synergus (Chondrichthyes, Hybodontiformes) from the Upper Triassic of the southwestern U.S.A., with a redescription of the genus". Journal of Vertebrate Paleontology. 37 (4): e1351980. Bibcode:2017JVPal..37E1980V. doi:10.1080/02724634.2017.1351980. ISSN 0272-4634.
  50. ^ Kues, Barry S. (1985). "Nonmarine molluscs from the Chinle Formation, Dockum Group (Upper Triassic), of Bull Canyon, Guadalupe County, New Mexico" (PDF). New Mexico Geological Society 36th Annual Fall Field Conference Guidebook. New Mexico Geological Society: 185–196. doi:10.56577/FFC-36.185.
  51. ^ Hunt, Adrian P.; Lockley, Martin G.; Lucas, Spencer G. (1993). "Vertebrate and invertebrate tracks and trackways from the Upper Triassic strata of the Tucumcari Basin, East-Central New Mexico, USA". New Mexico Museum of Natural History and Science Bulletin. 3: 199–201.