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 (Montana Group), Late/Upper Maastrichtian (70.6 - 66.0 Ma)
• Stratigraphically the quarry is placed in the lower third of the Hell Creek Formation (latest Maastrichtian), approximately 65 m below the Fort Union
•formational contact.
•The site is located in the lower third of the [Hell Creek] formation, approximately 65 m below the formational contact with the Fort Union Formation
• member-level stratigraphic resolution
Environment/lithology: lacustrine - small; sandstone and tabular mudstone
•
•2011: The depositional setting is interpreted as an oxbow lake in which many turtles aggregated and perished during a drought and where the slightly disarticulated carcasses were later washed together after the onset of rains.
Size class: macrofossils
Collected by Marmarth Research Foundation in 1996-2011
Collection methods: quarrying, surface (in situ),
• MRF, Marmarth Research Foundation, Marmarth, North Dakota, U.S.A.
•This locality is an approximately 125 square meter large quarry, in which a single, fossiliferous layer has been mined by MRF for vertebrate fossil remains over the course of the last 15 years.
Primary reference: W. G. Joyce and T. R. Lyson. 2011. New material of Gilmoremys lancensis nov. comb. (Testudines: Trionychidae) from the Hell Creek Formation and the diagnosis of plastomenid turtles. Journal of Paleontology 5(3):422-459 [R. Benson/R. Benson]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 122903: authorized by Roger Benson, entered by Roger Benson on 07.01.2012, edited by David Nicholson and Evangelos Vlachos
Creative Commons license: CC BY (attribution)
Taxonomic list
•
•
•2009: The locality, named Turtle Graveyard, has yielded an unsurpassed number of slightly disarticulated baenid turtle specimens including more than 70 shells, 35 skulls, and other postcranial remains partial, disarticulated trionychid turtle skeletons, teeth, and cartilaginous jaw elements from the ray fish Myledaphus, a lone unidentified crocodile dentary, and a few isolated bones from an unidentified theropod
Chondrichthyes | |
| |
Reptilia | |
Baenidae indet.1, Palatobaena cohen n. sp.2, "Peckemys brinkman" = Cedrobaena brinkman3, Cedrobaena putorius3
Palatobaena cohen n. sp.2 Lyson and Joyce 2009 turtle YPM 57498, (holotype) a complete uncrushed skull, mandible, and shell; MRF 257, complete skull and mandible; MRF 259, complete skull; MRF 263, complete skull; MRF 123, shell missing part of carapace
| |
Gilmoremys lancensis Gilmore 1916 turtle MRF 275, nearly complete skull; MRF 277, nearly complete skull; MRF 309, nearly complete skull and anteroposteriorly crushed skull; MRF 758, nearly complete skull (Fig. 6); MRF 759, partial skull, associated jaw and articulated anterior cervical column; MRF 525, nearly complete carapace; MRF 516, a left hyoplastron; MRF 565, a right hyoplastron; MRF 536, a right hyoplastron; MRF 534, a left hypoplastron; MRF 467, a right hypoplastron; MRF 549, a right xiphiplastron; MRF 575, a left xiphiplastron
| |
| |
| |
|