Big Turtle Cove locality (Cretaceous of the United States)

Also known as DMNH 6303

Where: Slope County, North Dakota (46.3° N, 104.0° W: paleocoordinates 52.6° N, 77.4° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Hell Creek Formation, Late/Upper Maastrichtian (70.6 - 66.0 Ma)

• Hell Creek Formation, Late Cretaceous (Maastrichtian); locality at base of formation, 68-70m below contact with overlying Fort Union Formation (Rollot et al. 2018)

• member-level stratigraphic resolution

Environment/lithology: terrestrial; sandstone

• "soft sandstone bed rich in rip-up clasts" Rollot et al. 2018

Size class: macrofossils

Collection methods: quarrying, surface (in situ),

• MRF, Marmarth Research Foundation, Marmarth, North Dakota, U.S.A. from 1997-2011; also Denver Museum of Natural HIstory

Primary reference: N. S. Vitek. 2012. Giant fossil soft-shelled turtles of North America. Palaeontologia Electronica 15(1):13A [R. Benson/R. Benson/O. Alfaro]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 141583: authorized by Roger Benson, entered by Roger Benson on 29.03.2013, edited by Evangelos Vlachos and Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Testudinata - Baenidae
Eubaena cephalica2 Hay 1904 turtle
DMNH 96004, a near complete cranium
 Testudines - Trionychidae
Axestemys infernalis n. sp.1 Joyce et al. 2019 softshell turtle
MRF 666, lower jaw; MRF 834-835, partial carapace and complete right hyoplastron and hypoplastron; MRF 849, partial carapace and dentary; MRF 700, preneural; MRF 631, costal 1; MRF 654, 676, costal; MRF 567, 675, 678 hyoplastron; MRF 699, partial pectoral girdle; MRF 586, MRF 661, femur; all specimens from Big Turtle Cove Locality, Slope County, North Dakota, USA; Hell Creek Formation, Late Cretaceous (Maastrichtian). MRF 567, MRF 631, MRF 654, MRF 675, MRF 676, MRF 699-700, and MRF 849 probably all belong to one individual. MRF 586, 661, 666, 678, and 834-835 probably all belong to a second individual
 Ornithischia -
Thescelosaurus sp.2 Gilmore 1913 ornithopod
 Choristodera -
Champsosaurus sp.2 Cope 1876 choristodere