PBDB Collection

Placerias Quarry, UCMP A269 (Triassic of the United States)

Where: Apache County, Arizona (34.4° N, 109.5° W: paleocoordinates 10.1° N, 48.1° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Mesa Redondo Member (Chinle Formation), Norian (228.0 - 208.5 Ma)

• 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

•

•Kent et al. 2019: Mesa Redondo Fm. falls between magnetozone 10n and PF8r, approximately 209.5Ma. 224.54–222.24Ma.

• group of beds-level stratigraphic resolution

Environment/lithology: wet floodplain; lenticular, brown, red, silty, sandy mudstone and paleosol/pedogenic, concretionary, gray, green, silty, carbonaceous claystone

• "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.

• "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.

Size classes: macrofossils, mesofossils, microfossils

Preservation: coprolite

Collected by C. L. Camp in 1931-1934; reposited in the UCMP

Collection methods: bulk, quarrying, mechanical, sieve,

Primary reference: 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]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 39160: authorized by Matthew Carrano, entered by Matthew Carrano on 21.05.2004, edited by Richard Butler, Kaitlin Maguire, Jonathan Tennant, Bethany Allen, Bryan Gee and Emma Dunne

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names

unclassified
-	Colobontidae indet.¹ Colobontidae indet.¹
Gnathostomata
-	Chondrichthyes "indet. B"²⁰, Chondrichthyes "indet. C"²⁰ Chondrichthyes "indet. B"²⁰ Huxley 1880 cartilaginous fish Chondrichthyes "indet. C"²⁰ Huxley 1880 cartilaginous fish
Chondrichthyes
Xenacanthiformes - Xenacanthidae	"Xenacanthus moorei" = Triodus moorei²⁰ "Xenacanthus moorei" = Triodus moorei²⁰ Woodward 1889 elasmobranch
Hybodontiformes - Acrodontidae	Acrodus sp.⁷ Acrodus sp.⁷ Agassiz 1834 elasmobranch MNA V3566
Hybodontiformes - Lonchidiidae	"Lissodus humblei" = Lonchidion humblei¹³ "Lissodus humblei" = Lonchidion humblei¹³ Murry 1981 elasmobranch
Phoebodontiformes - Phoebodontidae	Phoebodus sp.²⁰ Phoebodus sp.²⁰ St. John and Worthen 1875 elasmobranch MNA V3500
Gnathostomata
-	Osteichthyes "indet. B"²⁰, Osteichthyes "indet. E"²⁰, Osteichthyes "indet. F"²⁰, Osteichthyes "indet. H"²⁰, Osteichthyes "indet. I"²⁰, Osteichthyes "indet. J"²⁰, Osteichthyes "indet. K"²⁰, Osteichthyes "indet. M"²⁰, Osteichthyes "indet. O"²⁰, Osteichthyes "indet. P"²⁰ Osteichthyes "indet. B"²⁰ bony fish Osteichthyes "indet. E"²⁰ bony fish Osteichthyes "indet. F"²⁰ bony fish Osteichthyes "indet. H"²⁰ bony fish Osteichthyes "indet. I"²⁰ bony fish Osteichthyes "indet. J"²⁰ bony fish Osteichthyes "indet. K"²⁰ bony fish Osteichthyes "indet. M"²⁰ bony fish Osteichthyes "indet. O"²⁰ bony fish Osteichthyes "indet. P"²⁰ bony fish
Osteichthyes
Pholidopleuriformes - Pholidopleuridae	cf. Australosomus sp.¹ cf. Australosomus sp.¹ Pivetau 1930 ray-finned fish
Palaeonisciformes - Redfieldiidae	Redfieldiidae indet.²⁰, cf. Lasalichthys sp.¹³, cf. Cionichthys sp.¹³ Redfieldiidae indet.²⁰ Hutchinson 1973 Lasalichthyes sp. or Synorichthyes sp. cf. Lasalichthys sp.¹³ Schaeffer 1967 cf. Cionichthys sp.¹³ Schaeffer 1967
Palaeonisciformes - Palaeoniscidae	Gyrolepis sp.²⁰, cf. Turseodus sp.¹³ Gyrolepis sp.²⁰ Agassiz 1833 cf. Turseodus sp.¹³ Leidy 1857
Actinopteri
Semionotiformes - Semionotidae	Semionotidae indet.²⁰ Semionotidae indet.²⁰ Woodward 1890
Amphibia
Temnospondyli -	Temnospondyli indet.¹ Temnospondyli indet.¹ tetrapod At least 4 morphotypes
Salientia -	Salientia indet.¹⁹ Salientia indet.¹⁹ Laurenti 1768 frogs and relatives MNA V12365, left ilium; MNA V12366, left ilium; MNA V12369, partial maxilla
Temnospondyli - Metoposauridae	Apachesaurus gregorii¹⁰, "Buettneria perfecta" = Anaschisma browni¹⁰ Apachesaurus gregorii¹⁰ Hunt 1993 tetrapod MNA, small centra "Buettneria perfecta" = Anaschisma browni¹⁰ Branson 1905 tetrapod MNA V3039, 3045, unnumbered
Osteichthyes
Therapsida - Cynodontia	Cynodontia indet.⁸ Cynodontia indet.⁸ cynodont MNA V3618-3625, 3563
Dicynodontia - Stahleckeriidae	"Placerias gigas n. sp." = Placerias hesternus "Placerias gigas n. sp." = Placerias hesternus Lucas 1904 dicynodont
Reptilia
Diapsida -	Trilophosaurus sp.¹⁰, Trilophosaurus jacobsi n. sp.¹², Archosauriformes indet.⁷ Trilophosaurus sp.¹⁰ Case 1928 archosauromorph UCMP 32390, 25877, 25825, 25839, 25826, 25798, 25790, 25424, MNA V2924, 2956, 2928. Postcrania Trilophosaurus jacobsi n. sp.¹² Murry 1987 archosauromorph MNA V3192 (holotype), 3193, 3198, 3199, mandibular fragments. MNA V3194, 3197, maxillary fragments Archosauriformes indet.⁷ Gauthier 1986 archosauromorph
Archosauria -	Archosauria indet.⁶ Archosauria indet.⁶ Cope 1869 archosaur Teeth
Pterosauria -	? Pterosauria indet.¹⁰ ? Pterosauria indet.¹⁰ pterosaur
Lagerpetidae - Lagerpetidae	Dromomeron gregorii¹⁵ Dromomeron gregorii¹⁵ Nesbitt et al. 2009 ornithodiran UCMP 25815
Dinosauromorpha -	Dinosauriformes indet.¹⁴, Dinosauriformes indet.⁷ Dinosauriformes indet.¹⁴ Novas 1992 ornithodiran UCMP 25834, distal femur Dinosauriformes indet.⁷ Novas 1992 ornithodiran UCMP 25793, distal tibia
Saurischia -	Saurischia indet.⁷ Saurischia indet.⁷ saurischian UCMP 139622, femur. UCMP 25820, distal tibia
Ornithischia -	Ornithischia indet.¹, "Revueltosaurus hunti" = Krzyzanowskisaurus hunti² Ornithischia indet.¹ ornithischian "Revueltosaurus hunti" = Krzyzanowskisaurus hunti² Heckert 2002 ornithischian MNA V3195, 3200, teeth previously referred to Trilophosaurus jacobsi
Theropoda -	Theropoda indet.¹⁴ Theropoda indet.¹⁴ theropod UCMP 25830
Theropoda - Herrerasauridae	Herrerasauridae indet.⁶ Herrerasauridae indet.⁶ Benedetto 1973 herrerasaurid UCMP, 5 dorsal centra
Theropoda - Coelophysidae	Camposaurus arizonensis n. gen. n. sp.⁶ Camposaurus arizonensis n. gen. n. sp.⁶ Hunt et al. 1998 coelophysoid
Phytosauria - Parasuchidae	Rutiodon sp.¹, Leptosuchus sp.¹⁰, "Leptosuchus adamanensis" = Smilosuchus adamanensis¹⁰ Rutiodon sp.¹ Emmons 1856 archosaur Leptosuchus sp.¹⁰ Case 1922 archosaur Numerus specimens - see Long & Murry (1995) for details "Leptosuchus adamanensis" = Smilosuchus adamanensis¹⁰ Camp 1930 archosaur UCMP 27446, MNA V3024, 3025, squamosals
Phytosauria -	"Parasuchia indet." = Phytosauria⁷ "Parasuchia indet." = Phytosauria⁷ Jaeger 1828 phytosaur
Pseudosuchia -	Poposaurus gracilis¹⁰ Poposaurus gracilis¹⁰ Mehl 1915 archosaur UCMP & MNA collections. See Long & Murry (1995) for full specimen list
Pseudosuchia - Stagonolepididae	? Tecovasuchus sp.⁴, Tecovasuchus chatterjeei⁴, Desmatosuchus spurensis¹⁷, Acaenasuchus geoffreyi¹⁰, "Stagonolepis wellesi" = Calyptosuchus wellesi¹⁰ ? Tecovasuchus sp.⁴ Martz and Small 2006 aetosaur UCMP A269/126847, A269/136744 Tecovasuchus chatterjeei⁴ Martz and Small 2006 aetosaur MNA 2898, osteoderm Desmatosuchus spurensis¹⁷ Case 1920 aetosaur UCMP collections. See Long & Murry (1995) for full specimen list Acaenasuchus geoffreyi¹⁰ Long and Murry 1995 aetosaur MNA V3668, Pl. 3040, Pl. 3043, V3679, Pl. 2921, Pl. 2952, Pl. 3002, Pl. 3007, Pl. 3046, all plates "Stagonolepis wellesi" = Calyptosuchus wellesi¹⁰ Long and Ballew 1985 aetosaur UCMP collections. See Long & Murry (1995) for full specimen list
Pseudosuchia -	Revueltosaurus callenderi⁸ Revueltosaurus callenderi⁸ Hunt 1989 aetosaur MNA V3690
Pseudosuchia - Shuvosauridae	"Chatterjeea elegans" = Shuvosaurus inexpectatus¹⁰ "Chatterjeea elegans" = Shuvosaurus inexpectatus¹⁰ Chatterjee 1993 archosaur MNA V3743, femur
Loricata - Rauisuchidae	Postosuchus kirkpatricki¹⁰ Postosuchus kirkpatricki¹⁰ Chatterjee 1985 rauisuchid UCMP A269/27492, 27572, 27441, 140035, 124586, 27481, 27440, 27478, 27447, 27449, 27450, 27485, cranial material
Loricata -	Hesperosuchus agilis¹, Sphenosuchia indet.¹ Hesperosuchus agilis¹ Colbert 1952 crocodilian Sphenosuchia indet.¹ crocodilian "Large sphenosuchian"
-	Parrishia mccreai n. gen. n. sp.¹⁰ Parrishia mccreai n. gen. n. sp.¹⁰ Long and Murry 1995 archosaur UCMP 139623 (holotype), cervical. Referred vertebrae
Diapsida - Proterochampsidae	Proterochampsidae indet.¹ Proterochampsidae indet.¹ Romer 1966 archosauromorph
Diapsida - Doswelliidae	Vancleavea campi¹⁶ Vancleavea campi¹⁶ Long and Murry 1995 archosauromorph MNA V 3669, V3670, UCMP 152646, vertebrae
Diapsida -	Tecovasaurus murryi⁵, Syntomiprosopus sucherorum n. gen. n. sp.³, Uatchitodon schneideri¹¹ Tecovasaurus murryi⁵ Hunt and Lucas 1994 archosauromorph MNA V1699, 1704, teeth Syntomiprosopus sucherorum n. gen. n. sp.³ Heckert et al. 2021 archosauromorph Holotype: NCSM 29059–29060, a nearly complete right mandible found as two separate, but closely associated specimens in the same horizon. NCSM 29059 is the number assigned to the anterior (tooth-bearing) portion, NCSM 29060 is assigned to the posterior portion. Authors are certain that they pertain to the same individual, but there is no unambiguous point of contact between the two. Uatchitodon schneideri¹¹ Mitchell et al. 2010 archosauromorph MNA V3680, tooth
Diapsida - Tanystropheidae	Tanytrachelos sp.⁸ Tanytrachelos sp.⁸ Olsen 1979 archosauromorph Cervical rib
Diapsida -	Palacrodon sp.⁹ Palacrodon sp.⁹ Broom 1906 diapsid MNA V3684, jaw fragment; V11247, tooth
Eosuchia -	Lepidosauromorpha indet.¹ Lepidosauromorpha indet.¹ Benton 1983 crown diapsid
Eosuchia - Sphenodontidae	Sphenodontidae indet.¹² Sphenodontidae indet.¹² Cope 1871 lepidosaur MNA V3190, 3191, 3605-3612
Eosuchia - Kuehneosauridae	? Kuehneosauridae indet.¹ ? Kuehneosauridae indet.¹ Romer 1966 crown diapsid
Diapsida - Drepanosauridae	Drepanosauridae indet.¹⁸, cf. Drepanosauridae indet.¹⁸ Drepanosauridae indet.¹⁸ Berman and Reisz 1992 diapsid MNA V3637, posterior caudal vertebra. MNA V3652 (in part), posterior cervical vertebra, centrum cf. Drepanosauridae indet.¹⁸ Berman and Reisz 1992 diapsid MNA V3652 (in part), neural arch
Parareptilia - Procolophonidae	Procolophonidae indet.¹⁰ Procolophonidae indet.¹⁰ Lydekker 1889 parareptile
Coelacanthimorpha
Coelacanthiformes - Coelacanthidae	Coelacanthidae indet.²⁰ Coelacanthidae indet.²⁰ Agassiz 1843 coelacanth
Coelacanthiformes - Mawsoniidae	cf. Chinlea sp.¹ cf. Chinlea sp.¹ Schaeffer 1967 coelacanth
Osteichthyes
Dipnoi - Ceratodontidae	Ceratodus sp.¹³ Ceratodus sp.¹³ Agassiz 1838 lungfish

¹Heckert et al. 2005; ²Heckert et al. 2006; ³Heckert et al. 2021; ⁴Heckert et al. 2007; ⁵Hunt and Lucas 1994; ⁶Hunt et al. 1998; ⁷Irmis 2005; ⁸Kaye and Padian 1994; ⁹Kligman et al. 2018; ¹⁰Long and Murry 1995; ¹¹Mitchell et al. 2010; ¹²Murry 1987; ¹³Murry and Long 1989; ¹⁴Nesbitt et al. 2007; ¹⁵Nesbitt et al. 2009; ¹⁶Nesbitt et al. 2009; ¹⁷Parker 2008; ¹⁸Renesto et al. 2009; ¹⁹Stocker et al. 2019; ²⁰Tannenbaum 1983