east side of McDonald Coulee (Cretaceous of Canada)

Where: Alberta, Canada (49.1° N, 111.4° W: paleocoordinates 54.3° N, 73.2° W)

• coordinate estimated from map

When: Deadhorse Coulee Member (Milk River Formation), Late/Upper Santonian (85.8 - 83.5 Ma)

• The fluvial plain sediments, which consist of nonmarine shales, siltstones, sandstones, and coaly beds, are included in the Deadhorse Coulee Member. This unit sits above the Virgelle Member of the Milk River Formation (marine shoreface sandstone) and below the younger marine Pakowki Formation (deposition beginning at approximately 81 Ma, following a non-depositional unconformity

Environment/lithology: terrestrial; siltstone

• Both sedimentological and palynological studies support an interpretation of the Milk River Formation as environmentally transitional, with sediments at the base of the formation having been deposited in a marine, open shelf, storm-dominated environment, and sediments at the top of the formation deposited in a fluvial plain environment
• nonmarine shales, siltstones, sandstones, and coaly beds

Size class: macrofossils

Collected by L. Sternberg in 1950

• Material deposited in ROM, Royal Ontario Museum, Canada.

Primary reference: S. E. Edgar, D. B. Brinkman, M. J. Ryan and D. C. Evans. 2022. A new plastomenid trionychid (Testudines: Pan-Trionychidae) from Milk River Formation of southern Alberta (Cretaceous: Santonian). Canadian Journal of Earth Sciences 59:205-215 [E. Vlachos/E. Vlachos]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 224584: authorized by Evangelos Vlachos, entered by Evangelos Vlachos on 21.03.2022

Creative Commons license: CC BY (attribution)

Taxonomic list

• In addition to the turtle described here, the Milk River Formation contains a diverse assemblage of vertebrates including fish (Brinkman et al. 2017), amphibians (Gardner and DeMar 2013), lizards (Gao and Fox 1998), turtles (Brinkman 2003), crocodylomorphs (Wu and Brinkman 1993), and dinosaurs (Baszio 1997; Evans et al. 2013).
Show authors, comments, and common names
Reptilia
 Testudines - Pantrionychidae
Jimemys glaebosus n. gen. n. sp.
Jimemys glaebosus n. gen. n. sp. Edgar et al. 2022 turtle
ROM 56647, a partial nuchal and posterior carapace consisting of left and right costals VI–VIII, left costal V, right partial hyo-hypoplastron, right complete xiphiplastron, incomplete left posterior xiphiplastron, five partial neurals, and partial femur diaphysis.