Placerias Quarry, UCMP A269: Norian, Arizona
collected by C. L. Camp 1931-1934

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Colobontidae indet.
Heckert et al. 2005
Chondrichthyes
Chondrichthyes informal indet. B Huxley 1880
Tannenbaum 1983 1 element
Chondrichthyes informal indet. C Huxley 1880
Tannenbaum 1983 1 element
Chondrichthyes - Xenacanthiformes - Xenacanthidae
Xenacanthus moorei (Woodward 1889)
Tannenbaum 1983 13 elements
recombined as Triodus moorei
Chondrichthyes - Hybodontiformes - Acrodontidae
Acrodus sp. Agassiz 1838
Irmis 2005 1 specimen
MNA V3566
Chondrichthyes - Hybodontiformes - Lonchidiidae
Lonchidion cf. humblei Murry 1981
Tannenbaum 1983 1 element
    = Lissodus humblei Murry 1981
Murry and Long 1989
original and current combination Lonchidion humblei
Chondrichthyes - Phoebodontiformes - Phoebodontidae
Phoebodus sp. St. John and Worthen 1875
Tannenbaum 1983 1 element
MNA V3500
Osteichthyes
Osteichthyes informal indet. B Huxley 1880
Tannenbaum 1983 2 elements
Osteichthyes informal indet. E Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. F Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. H Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. I Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. J Huxley 1880
Tannenbaum 1983 2 elements
Osteichthyes informal indet. K Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. M Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. O Huxley 1880
Tannenbaum 1983 1 element
Osteichthyes informal indet. P Huxley 1880
Tannenbaum 1983 1 element
Actinopteri - Palaeonisciformes - Palaeoniscidae
Gyrolepis sp. Agassiz 1843
Tannenbaum 1983 1 element
Palaeoniscidae indet. Vogt 1852
Tannenbaum 1983 9 elements
    = cf. Turseodus sp. Leidy 1857
Murry and Long 1989
Actinopteri - Palaeonisciformes - Redfieldiidae
Redfieldiidae indet. Hutchinson 1973
Tannenbaum 1983 1 element
Lasalichthyes sp. or Synorichthyes sp.
Cionichthys sp. Schaeffer 1967
Tannenbaum 1983 1 element
    = cf. Cionichthys sp. Schaeffer 1967
Murry and Long 1989
Osteichthyes informal indet. A Huxley 1880
Tannenbaum 1983 3 elements
    = cf. Lasalichthys sp. Schaeffer 1967
Murry and Long 1989
Actinopteri - Pholidopleuriformes - Pholidopleuridae
cf. Australosomus sp. Pivetau 1930
Heckert et al. 2005
Actinopteri - Semionotiformes - Semionotidae
Semionotidae indet. Woodward 1890
Tannenbaum 1983 4 elements
Ceratodontidae
Ceratodontidae indet. Gill 1872
Tannenbaum 1983 14 elements
    = Ceratodus sp. Agassiz 1838
Murry and Long 1989
Coelacanthimorpha - Coelacanthiformes - Coelacanthidae
Coelacanthidae indet. Agassiz 1843
Tannenbaum 1983 2 elements
cf. Chinlea sp. Schaeffer 1967
Heckert et al. 2005
unclassified
Temnospondyli indet. (von Zittel 1887)
Heckert et al. 2005
At least 4 morphotypes
Metoposauridae
Apachesaurus gregorii Hunt 1993
Long and Murry 1995 1 specimen
MNA, small centra
Buettneria perfecta Case 1922
Long and Murry 1995 3 specimens
recombined as Koskinonodon perfectus
MNA V3039, 3045, unnumbered
Reptilia - Procolophonidae
Procolophonidae indet. Lydekker 1889
Long and Murry 1995
Reptilia
Trilophosaurus sp. Case 1928
Long and Murry 1995 11 specimens
UCMP 32390, 25877, 25825, 25839, 25826, 25798, 25790, 25424, MNA V2924, 2956, 2928. Postcrania
Trilophosaurus jacobsi n. sp. Murry 1987
Murry 1987 6 specimens
MNA V3192 (holotype), 3193, 3198, 3199, mandibular fragments. MNA V3194, 3197, maxillary fragments
Crosbysaurus harrisae Heckert 2004
Heckert and Lucas 2006
    = Archosauriformes indet. Gauthier 1986
Irmis 2005
cf. Uatchitodon sp. Sues 1991
Kaye and Padian 1994 1 specimen
MNA V3680, tooth
    = Uatchitodon schneideri Mitchell et al. 2010
Mitchell et al. 2010
Vancleavea campi Long and Murry 1995
Nesbitt et al. 2009 3 specimens
MNA V 3669, V3670, UCMP 152646, vertebrae
Reptilia - Proterochampsidae
Proterochampsidae indet. Romer 1966
Heckert et al. 2005
Reptilia
cf. Coelophysis sp. Cope 1889
Murry and Long 1989
Teeth
    = Archosauria indet. Cope 1869
Hunt et al. 1998
Reptilia - Lagerpetonidae
Dromomeron gregorii Nesbitt et al. 2009
Nesbitt et al. 2009 1 specimen
UCMP 25815
Reptilia
? Anchisauridae indet. Marsh 1885
Tannenbaum 1983 1 specimen
UCMP 25793, distal tibia
    = Anchisauridae indet. Marsh 1885
Murry and Long 1989
    = Prosauropoda indet. Huene 1920
Long and Murry 1995
    = Dinosauriformes indet. Novas 1992
Irmis 2005
Dinosauriformes indet. Novas 1992
Nesbitt et al. 2007 1 specimen
UCMP 25834, distal femur
Camposaurus arizonensis n. gen., n. sp. Hunt et al. 1998
Hunt et al. 1998 1 specimen
nomen dubium belonging to Dinosauria
Reptilia - Saurischia
Ceratosauria indet. (Marsh 1884)
Long and Murry 1995
UCMP 139622, femur. UCMP 25820, distal tibia
    = Saurischia indet. Seeley 1888
Irmis 2005
Reptilia - Theropoda
Theropoda indet. Marsh 1881
Nesbitt et al. 2007 1 specimen
UCMP 25830
Reptilia - Herrerasauridae
Chindesaurus bryansmalli Long and Murry 1995
Long and Murry 1995 1 specimen
UCMP, 5 dorsal centra
    = Herrerasauridae indet. Benedetto 1973
Hunt et al. 1998
Reptilia - Ornithischia
Fabrosauridae indet. Galton 1972
Jacobs and Murry 1980
    = Ornithischia indet. Seeley 1888
Heckert et al. 2005
Reptilia
? Pterosauria indet. (Kaup 1834)
Long and Murry 1995
Parrishia mccreai n. gen., n. sp. Long and Murry 1995
Long and Murry 1995 13 specimens
nomen dubium belonging to Archosauria
UCMP 139623 (holotype), cervical. Referred vertebrae
Reptilia - Shuvosauridae
Chatterjeea elegans Long and Murry 1995
Long and Murry 1995 1 specimen
synonym of Shuvosaurus inexpectatus
MNA V3743, femur
Reptilia
Acaenasuchus geoffreyi Long and Murry 1995
Long and Murry 1995 9 specimens
MNA V3668, Pl. 3040, Pl. 3043, V3679, Pl. 2921, Pl. 2952, Pl. 3002, Pl. 3007, Pl. 3046, all plates
Desmatosuchus haplocerus (Cope 1892)
Long and Murry 1995 620 specimens
UCMP collections. See Long & Murry (1995) for full specimen list
    = Desmatosuchus spurensis Case 1920
Parker 2008
Stagonolepis wellesi (Long and Ballew 1985)
Long and Murry 1995 485 specimens
original and current combination Calyptosuchus wellesi
UCMP collections. See Long & Murry (1995) for full specimen list
? Tecovasuchus sp. Martz and Small 2006
Heckert et al. 2007 2 elements
UCMP A269/126847, A269/136744
Tecovasuchus chatterjeei Martz and Small 2006
Heckert et al. 2007 1 element
MNA 2898, osteoderm
Revueltosaurus hunti Heckert 2002
Heckert et al. 2006 2 elements
MNA V3195, 3200, teeth previously referred to Trilophosaurus jacobsi
Sphenosuchia indet. ()
Heckert et al. 2005
invalid subgroup of Crocodylomorpha
"Large sphenosuchian"
Hesperosuchus agilis Colbert 1952
Heckert et al. 2005
Postosuchus kirkpatricki Chatterjee 1985
Long and Murry 1995
UCMP A269/27492, 27572, 27441, 140035, 124586, 27481, 27440, 27478, 27447, 27449, 27450, 27485, cranial material
Poposaurus gracilis Mehl 1915
Long and Murry 1995 29 specimens
UCMP & MNA collections. See Long & Murry (1995) for full specimen list
Reptilia - Parasuchidae
Rutiodon sp. Emmons 1856
Heckert et al. 2005
Leptosuchus sp. Case 1922
Long and Murry 1995
Numerus specimens - see Long & Murry (1995) for details
Leptosuchus adamanensis (Camp 1930)
Long and Murry 1995 3 specimens
recombined as Smilosuchus adamanensis
UCMP 27446, MNA V3024, 3025, squamosals
Reptilia
Paleorhinus sp. Williston 1904
Murry and Long 1989 1 specimen
    = Parasuchia indet. Huxley
Irmis 2005
synonym of Phytosauria
Tecovasaurus murryi Hunt and Lucas 1994
Hunt and Lucas 1994 5 specimens
MNA V1699, 1704, teeth
Reptilia - Tanystropheidae
Tanytrachelos sp. Olsen 1979
Kaye and Padian 1994 1 specimen
Cervical rib
Reptilia
Lepidosauromorpha indet. (Benton 1983)
Heckert et al. 2005
Reptilia - Rhynchocephalia - Sphenodontidae
Sphenodontidae indet. Cope 1869
Murry 1987 10 specimens
MNA V3190, 3191, 3605-3612
Reptilia - Kuehneosauridae
? Kuehneosauridae indet. Romer 1966
Heckert et al. 2005
Reptilia - Drepanosauridae
Drepanosauridae indet. Berman and Reisz 1992
Renesto et al. 2009 3 elements
MNA V3637, posterior caudal vertebra. MNA V3652 (in part), posterior cervical vertebra, centrum
cf. Drepanosauridae indet. Berman and Reisz 1992
Renesto et al. 2009 1 element
MNA V3652 (in part), neural arch
Reptilia
Palacrodon sp. Broom 1906
Kligman et al. 2018
MNA V3684, jaw fragment; V11247, tooth
Cynodontia
Cynodontia indet. Owen 1861
Kaye and Padian 1994 9 specimens
MNA V3618-3625, 3563
Stahleckeriidae
Placerias gigas n. sp. Camp and Welles 1956
1600 specimens
synonym of Placerias hesternus
see common names

Geography
Country:United States State/province:Arizona County:Apache
Coordinates: 34.4° North, 109.5° West (view map)
Paleocoordinates:10.1° North, 48.1° West
Basis of coordinate:stated in text
Geographic resolution:outcrop
Time
Period:Triassic Epoch:Late/Upper Triassic
Stage:Norian 10 m.y. bin:Triassic 4
Key time interval:Norian
Age range of interval:228.00000 - 208.50000 m.y. ago
Stratigraphy
Formation:Chinle Member:Mesa Redondo
Stratigraphic resolution:group of beds
Stratigraphy comments: One of two nearly adjacent quarries (the second is the Downs Quarry, 30 metres from the Placerias Quarry). Early workers placed the Placerias Quarry low in the Blue Mesa Member, while Lucas et al. (1997) assigned it to the Mesa Redondo (= Bluewater Creek) Member. Parker (2005) noted that the lithology of the beds and the local presence of the Shinarump Member (the basal member of the Chinle Formation) supports the Mesa Redondo assignment. Earliest Adamanian LVF
Lithology and environment
Primary lithology:lenticular,brown,red silty,sandy mudstone
Secondary lithology:paleosol/pedogenic,concretionary,gray,green silty,carbonaceous claystone
Lithology description: "The original quarry horizon was a bed of limestone concretions from which many broken or poorly preserved bones were recovered; this gives way to typical reddish-brown Chinle mudstones and silts, with occasional sandstone lenses, in which 'two fossiliferous levels [were] separated by 2 feet of barren sediments'...Calcareous nodules, gypsum lenses, carbonaceous particles, and yellow-brown sulfurous deposits are common"...fossils in "clay-rich mudstone...[that] varies in color from a dark to light olive gray, with little change in mineral composition. These mudstones are dominantly smectite with 10%-25% quartz and traces of feldspar, gypsum, and calcite...'chunks' of this carbonaceous material occur as dark gray and black specks usually less than a millimeter or two in diameter...the calcareous nodules...are autochthonous...[with] a micritic texture." Nodules interpreted as palustrine carbonates.
Environment:wet floodplain
Geology comments: "a soft, vegetated pond bottom or other quiet water deposit"; "ancient pond or marsh, an environment of low-energy water flow that may have been seasonally low or dry (as indicated by numerous evaporites." But re-interpreted as a humid-environment soil.
Taphonomy
Modes of preservation:body,coprolite
Degree of concentration:-seasonal
Size of fossils:macrofossils,mesofossils,microfossils
Preservation of anatomical detail:variable
Articulated whole bodies:none
Associated major elements:none
Disassociated major elements:many
Disassociated minor elements:many
Fragmentation:frequent
Bioerosion:occasional
Feeding/predation traces:tooth marks,gastric dissolution
Spatial resolution:autochthonous
Collection methods and comments
Collection methods:bulk,selective quarrying,mechanical,sieve,field collection
Reason for describing collection:general faunal/floral analysis
Museum repositories:UCMP
Collectors:C. L. Camp Collection dates:1931-1934
Metadata
Database number:39160
Authorizer:M. Carrano, R. Butler, P. Mannion, A. Dunhill Enterer:M. Carrano, R. Butler, J. Tennant, B. Allen, K. Maguire
Modifier:M. Carrano Research group:vertebrate
Created:2004-05-21 16:43:16 Last modified:2013-02-07 15:25:32
Access level:the public Released:2004-05-21 16:43:16
Creative Commons license:CC BY
Reference information

Primary reference:

32081. C. L. Camp and S. P. Welles. 1956. Triassic dicynodont reptiles. Part 1. Memoirs of the University of California 13:255-341 [R. Butler/R. Butler/R. Butler]

Secondary references:

27981ETE K. D. Angielczyk. 2002. A selective annotation of published Triassic vertebrates from the University of California Museum of Paleontology collection. In A. B. Heckert, S. G. Lucas (eds.), New Mexico Museum of Natural History and Science Bulletin 21:297-301 [M. Carrano/M. Carrano/P. Wagner]
19347ETE A. R. Fiorillo, K. Padian, and C. Musikasinthorn. 2000. Taphonomy and depositional setting of the Placerias Quarry (Chinle Formation: Late Triassic, Arizona). Palaios 15:373-386 [M. Carrano/M. Carrano]
25555ETE A. B. Heckert and S. G. Lucas. 1998. First use of ornithischian dinosaurs for biostratigraphic zonation of the Upper Triassic. Albertiana 20:58-63 [M. Carrano/M. Carrano]
31129 A. B. Heckert and S. G. Lucas. 2002. Acaenasuchus geoffreyi (Archosauria: Aetosauria) from the Upper Triassic Chinle Group: juvenile of Desmatosuchus haplocerus. In A. B. Heckert, S. G. Lucas (eds.), Upper Triassic Stratigraphy and Paleontology. New Mexico Museum of Natural History and Science Bulletin 21:205-214 [R. Butler/R. Butler]
46019 A. B. Heckert, S. G. Lucas, and A. P. Hunt. 2005. Triassic vertebrate fossils in Arizona. Vertebrate Paleontology in Arizona. New Mexico Museum of Natural History and Science Bulletin 29:16-44 [P. Mannion/J. Tennant]
32141 A. B. Heckert, S. G. Lucas, L. F. Rinehart, J. A. Spielmann, A. P. Hunt and R. Kahle. 2006. Revision of the archosauromorph reptile Trilophosaurus, with a description of the first skull of Trilophosaurus jacobsi, from the Upper Triassic Chinle Group, West Texas, USA. Palaeontology 49(3):621-640 [R. Butler/R. Butler]
24941ETE A. B. Heckert and S. G. Lucas. 2006. Micro- and small vertebrate biostratigraphy and biochronology of the Upper Triassic Chinle Group, southwestern USA. In J. D. Harris, S. G. Lucas, J. A. Spielmann, M. G. Lockley, A. R. C. Milner, J. I. Kirkland (eds.), The Triassic-Jurassic Terrestrial Transition. New Mexico Museum of Natural History and Science Bulletin 37:94-104 [M. Carrano/M. Carrano/P. Wagner]
43558 A. B. Heckert, J. A. Spielmann, S. G. and A. P. Hunt. 2007. Biostratigraphic utility of the Upper Triassic aetosaur Tecovasuchus (Archosauria: Stagonolepididae), an index taxon of St. Johnsian (Adamanian: late Carnian) time. New Mexico Museum of Natural History and Science Bulletin 41:51-57 [R. Butler/R. Butler]
31344 A. P. Hunt, A. B. Heckert, S. G. Lucas and A. Downs. 2002. The distribution of the enigmatic reptile Vancleavea in the Upper Triassic Chinle Group of the western United States. In A. B. Heckert, S. G. Lucas (eds.), Upper Triassic Stratigraphy and Paleontology, New Mexico Museum of Natural History and Science Bulletin 21:269-273 [R. Butler/R. Butler]
15400ETE A. P. Hunt and S. G. Lucas. 1994. Ornithischian dinosaurs from the Upper Triassic of the United States. In N. C. Fraser & H.-D. Sues (eds.), In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods. Cambridge University Press, Cambridge 227-241 [M. Carrano/M. Carrano]
13905ETE A. P. Hunt, S. G. Lucas, A. B. Heckert, R. M. Sullivan, and M. G. Lockley. 1998. Late Triassic dinosaurs from the western United States. Géobios 31(4):511-531 [M. Carrano/M. Carrano/J. Alroy]
24406ETE R. B. Irmis. 2005. A review of the vertebrate fauna of the Lower Jurassic Navajo Sandstone in Arizona. In R. D. McCord (ed.), Vertebrate Paleontolgy of Arizona. Mesa Southwest Museum Bulletin 11:55-71 [M. Carrano/M. Carrano]
15399ETE R. B. Irmis. 2005. The vertebrate fauna of the Upper Triassic Chinle Formation in northern Arizona. In S. J. Nesbitt, W. G. Parker, & R. B. Irmis (eds.), Guidebook to the Triassic Formations of the Colorado Plateau in Northern Arizona: Geology, Paleontology, and History. Mesa Southwest Museum Bulletin 9:63-88 [M. Carrano/M. Carrano/M. Carrano]
30645ETE L. L. Jacobs. 1985. Small vertebrate fossils from the Chinle Formation (Triassic) near St. Johns, Arizona. National Geographic Society Research Reports (1979) 20:417-419 [M. Carrano/M. Carrano]
10591 L. L. Jacobs and P. A. Murry. 1980. The vertebrate community of the Triassic Chinle Formation near St. Johns, Arizona. Aspects of Vertebrate History: Essays in Honor of Edwin Harris Colbert, L. L. Jacobs (ed.), Museum of Northern Arizona Press 55-71 [M. Carrano/M. Carrano/M. Carrano]
14611ETE F. T. Kaye and K. Padian. 1992. Microvertebrates from the Placerias Quarry (Chinle Formation, Carnian, Arizona): a window on Late Triassic diversity. Journal of Vertebrate Paleontology 12(3, suppl.):36A [M. Carrano/M. Carrano/M. Carrano]
10575ETE F. T. Kaye and K. Padian. 1994. Microvertebrates from the Placerias Quarry: a window on Late Triassic vertebrate diversity in the American Southwest. In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods, N. C. Fraser and H.-D. Sues (eds.), Cambridge University Press 172-196 [M. Carrano/M. Carrano/M. Carrano]
66904 B. T. Kligman, A. D. Marsh, and W. G. Parker. 2018. First records of diapsid Palacrodon from the Norian, Late Triassic Chinle Formation of Arizona, and their biogeographic implications. Acta Palaeontologica Polonica 63(1):117-127 [A. Dunhill/B. Allen]
14122ETE R. A. Long and P. A. Murry. 1995. Late Triassic (Carnian and Norian) tetrapods from the southwestern United States. New Mexico Museum of Natural History and Science Bulletin 4:1-254 [M. Carrano/M. Carrano/M. Carrano]
44702 S. G. Lucas. 1993. The Chinle Group: revised stratigraphy and biochronology of Upper Triassic nonmarine strata in the western United States. In M. Morales (ed.), Aspects of Mesozoic Geology and Paleontology of the Colorado Plateau. Museum of Northern Arizona Bulletin 59:27-50 [M. Carrano/M. Carrano]
25567ETE S. G. Lucas, A. B. Heckert, and A. P. Hunt. 1997. Stratigraphy and biochronological significance of the Late Triassic Placerias quarry, eastern Arizona (U.S.A.). Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 203(1):23-46 [M. Carrano/M. Carrano]
31640 S. G. Lucas, A. P. Hunt, and J. A. Spielmann. 2007. A new aetosaur from the Upper Triassic (Adamanian: Carnian) of Arizona. In S. G. Lucas, J. A. Spielmann (eds.), Triassic of the American West, New Mexico Museum of Natural History and Science Bulletin 40:241-247 [R. Butler/R. Butler]
34225 J. S. Mitchell, A. B. Heckert, and H.-D. Sues. 2010. Grooves to tubes: evolution of the venom delivery system in a Late Triassic reptile. Naturwissenschaften 97:1117-1121 [R. Butler/R. Butler/R. Butler]
32082 P. A. Murry. 1987. New reptiles from the Upper Triassic Chinle Formation of Arizona. Journal of Paleontology 61(4):773-786 [R. Butler/R. Butler]
12930ETE P. A. Murry and R. A. Long. 1989. Geology and paleontology of the Chinle Formation, Petrified Forest National Park and vicinity, Arizona and a discussion of vertebrate fossils of the southwestern Upper Triassic. In S. G. Lucas and A. P. Hunt (eds.), Dawn of the Age of Dinosaurs in the American Southwest, New Mexico Museum of Natural History, Albuquerque 29-64 [M. Carrano/M. Carrano/M. Carrano]
24249ETE S. J. Nesbitt, R. B. Irmis, and W. G. Parker. 2007. A critical re-evaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243 [M. Carrano/M. Carrano]
30105 S. J. Nesbitt, R. B. Irmis, W. G. Parker, N. D. Smith, A. H. Turner and T. Rowe. 2009. Hindlimb osteology and distribution of basal dinosauromorphs from the Late Triassic of North America. Journal of Vertebrate Paleontology 29(2):498-516 [R. Butler/R. Butler/M. Carrano]
31327 S. J. Nesbitt, M. R. Stocker, B. J. Small and A. Downs. 2009. The osteology and relationships of Vancleavea campi (Reptilia: Archosauriformes). Zoological Journal of the Linnean Society 157:814-864 [R. Butler/R. Butler/R. Butler]
31632 W. G. Parker. 2005. Faunal review of the Upper Triassic Chinle Formation of Arizona. In R. D. McCord (ed.), Vertebrate Paleontology of Arizona, Mesa Southwest Museum Bulletin 11:34-54 [R. Butler/R. Butler]
32140 W. G. Parker. 2008. Description of new material of the aetosaur Desmatosuchus spuriensis (Archosauria: Suchia) from the Chinle Formation of Arizona and a revision of the genus. PaleoBios 28:1-40 [R. Butler/R. Butler]
32240 S. Renesto, J. A. Spielmann, S. G. Lucas and G. T. Spagnoli. 2010. The taxonomy and paleobiology of the Late Triassic (Carnian-Norian: Adamanian-Apachean) drepanosaurs (Diapsida: Archosauromorpha: Drepanosauromorpha). New Mexico Museum of Natural History and Science, Bulletin 46:1-81 [R. Butler/R. Butler]
32083 S. C. Renesto, J. A. Spielmann, and S. G. Lucas. 2009. The oldest record of drepanosaurids (Reptilia, Diapsida) from the Late Triassic (Adamanian Placerias Quarry, Arizona, USA) and the stratigraphic range of the Drepanosauridae. Neues Jahrbuch für Paläontologie und Geologie, Abhandlungen 252(3):315-325 [R. Butler/R. Butler]
32084 H.-D. Sues. 1996. A reptilian tooth with apparent venom canals from the Chinle Group (Upper Triassic) of Arizona. Journal of Vertebrate Paleontology 16:571-572 [R. Butler/R. Butler]
11081ETE F. A. Tannenbaum. 1983. The microvertebrate fauna of the Placerias and Downs Quarries, Chinle Formation (Upper Triassic) near St. Johns, Arizona. University of California, Berkeley 1-117 [M. Carrano/M. Carrano/M. Carrano]
35610 J. C. Weinbaum. 2011. The skull of Postosuchus kirkpatricki (Archosauria: Paracrocodyliformes) from the Upper Triassic of the United States. PaleoBios 30(1):18-44 [R. Butler/R. Butler]
23520ETE D. B. Weishampel, P. M. Barrett, R. A. Coria, J. Le Loeuff, X. Xu, X. Zhao, A. Sahni, E. M. P. Gomani, and C. R. Noto. 2004. Dinosaur distribution. In D. B. Weishampel, H. Osmolska, and P. Dodson (eds.), The Dinosauria (2nd edition). University of California Press, Berkeley 517-606 [M. Carrano/M. Carrano]
37966 S. P. Welles. 1972. Fossil-hunting for tetrapods in the Chinle Formation: a brief pictorial history. In C. S. Breed & W. J. Breed (ed.), Investigations in the Triassic Chinle Formation. Museum of Northern Arizona Bulletin 47:13-18 [M. Carrano/M. Carrano]