OMNH V239, Mussentuchit (Cretaceous of the United States)

Where: Emery County, Utah (39.0° N, 111.9° W: paleocoordinates 40.4° N, 74.0° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Mussentuchit Member (Cedar Mountain Formation), Early/Lower Cenomanian (99.6 - 93.5 Ma)

• 4 m below overlying Naturita Fm.

•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: "channel"; 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 14399: 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

Mammalia
 Theriamorpha - Spalacotheriidae
Spalacolestes cretulablatta1 Cifelli and Madsen 1999 mammal
Spalacotheridium noblei1 Cifelli and Madsen 1999 mammal
 Theriamorpha -
Sinbadelphys schmidti2 Cifelli 2004 metatherian
Dakotadens pertritus3 Cifelli et al. 2016 metatherian
OMNH 25813, 25798, 25803
Adelodelphys muizoni2 Cifelli 2004 metatherian
Culicolestes kielanae n. gen. n. sp.3 Cifelli et al. 2016 mammal
OMNH 25809
? Culicolestes kielanae3 Cifelli et al. 2016 mammal
OMNH 25802
 Multituberculata -
Bryceomys intermedius5 Eaton and Cifelli 2001 multituberculate
including tentatively referred M1
Cedaromys bestia5 Eaton and Nelson 1991 multituberculate
Cedaromys parvus n. sp.5 Eaton and Cifelli 2001 multituberculate
holotype M1, OMNH 25747; including two tentatively referred m1s
cf. Paracimexomys cf. robisoni5 Eaton and Nelson 1991 multituberculate
cf. Paracimexomys perplexus5 Eaton and Cifelli 2001 multituberculate
 Eutriconodonta - Triconodontidae
Jugulator amplissimus Cifelli and Madsen 1998 mammal
Astroconodon delicatus n. sp. Cifelli and Madsen 1998 mammal
Corviconodon utahensis Cifelli and Madsen 1998 mammal
Reptilia
 Squamata -
Dimekodontosaurus madseni8 Nydam 2002 squamates
 Squamata - Polyglyphanodontidae
"? Polyglyphanodontinae indet." = Polyglyphanodontidae4, Dicothodon moorensis n. gen. n. sp.7, Bicuspidon numerosus9
"? Polyglyphanodontinae indet." = Polyglyphanodontidae4 Gilmore 1942 squamates
OMNH 32639
Dicothodon moorensis n. gen. n. sp.7 Nydam 1999 squamates
OMNH 29771
Bicuspidon numerosus9 Nydam and Cifelli 2002 squamates
 Theropoda - Elongatoolithidae
Macroelongatoolithus carlylei10 Jensen 1970 theropod
TMP 98.107.4, 98.107.15, 98.107.18, 98.107.22
Amphibia
 Temnospondyli - Albanerpetontidae
Albanerpetontidae indet.6 Fox and Naylor 1982 tetrapod
OMNH 26210
Albanerpeton cf. nexuosus6 Estes 1981 tetrapod
OMNH 26222