Where: Emery County, Utah (38.7° N, 111.2° W: paleocoordinates 40.0° N, 73.4° W)
• coordinate estimated from map
• small collection-level geographic resolution
When: Mussentuchit Member (Cedar Mountain Formation), Early/Lower Cenomanian (99.6 - 93.5 Ma)
• 8 m below overlying Naturita Fm.
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•A radiometric age of 98.37 ± 0.07 Ma was obtained by the OMNH from volcanic ash within the Mussentuchit Member (Cifelli and others, 1997, 1999). Additional ages by Garrison and others (2007) ranging from 96.7 ± 0.5 to 98.2 ±0.6 Ma indicate that the Mussentuchit Member was deposited over an interval of 1.5 Ma during the early Cenomanian and supports a correlation with the siliceous marine Mowry Shale to the north, which is well-constrained from 40Ar/39Ar sanidine ages obtained from bentonite beds that bracket the Mowry in Wyoming; the basal Arrow Creek Bentonite is 98.5 ± 0.5 Ma and the capping Clay Spur Bentonite is 97.2 ± 0.7 Ma (Obradovich, 1993; Ogg and Hinnov, 2012; Sprinkel and others, 2012) near the base of the Upper Cretaceous. Tucker et al. 2020 also suggested a likely depositional age of ~96-94Ma for the Musseuntuchit member.
• group of beds-level stratigraphic resolution
Environment/lithology: crevasse splay; lithology not reported
Size classes: macrofossils, mesofossils
Primary reference: R. L. Cifelli and S. K. Madsen. 1998. Triconodont mammals from the medial Cretaceous of Utah. Journal of Vertebrate Paleontology 18(2):403-411 [J. Alroy/J. Alroy/M. Carrano]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 14405: authorized by John Alroy, entered by John Alroy on 21.09.1998, edited by Roger Benson and Matthew Carrano
Creative Commons license: CC BY (attribution)
Taxonomic list
Reptilia | |
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Harmodontosaurus emeryensis n. gen. n. sp.6
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Mammalia | |
Astroconodon delicatus Cifelli and Madsen 1998 mammal | |
cf. Paracimexomys perplexus4, cf. Paracimexomys cf. robisoni4, Bryceomys intermedius n. sp.4, Cedaromys parvus4, Cedaromys bestia4, Janumys erebos4, Ameribaatar zofiae4
Bryceomys intermedius n. sp.4 Eaton and Cifelli 2001 multituberculate including tentatively referred m2
Ameribaatar zofiae4 Eaton and Cifelli 2001 multituberculate ml, OMNH 32990 (partial); m2, 32993; M2, 32989 (posterior fragment), 32991 (partial)
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Spalacotheriidae indet.3, Spalacolestes inconcinnus n. sp.3, Spalacolestes cretulablatta1, Spalacotheridium noblei1
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Pariadens mckennai n. sp.2
Pariadens mckennai n. sp.2 Cifelli 2004 metatherian OMNH 33072, holotype left m4; OMNH 33076 (m1) and 33971 (m2 or 3)
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