Fort Yates area (Cretaceous of the United States)

Where: Sioux County, North Dakota (46.1° N, 100.6° W: paleocoordinates 51.6° N, 73.9° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

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

• Plesiosaur vertebrate and ammonite might be from th Pierre Shale Formation

• bed-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size class: macrofossils

Collected by E. D. Cope in 1893; reposited in the ANSP

Primary reference: E. Daeschler and A. R. Fiorillo. 1989. Rediscovery of fossil material at the Academy of Natural Sciences of Philadelphia from Edward Drinker Cope's 1893 expedition to the Dakotas. The Mosasaur 4:143-148 [M. Carrano/K. Maguire/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 57919: authorized by Matthew Carrano, entered by Kaitlin Maguire on 06.01.2006, edited by John Alroy

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Ammonitida - Scaphitidae
"Scaphites cf. nicolletii" = Hoploscaphites nicolletii, Scaphites sp.
"Scaphites cf. nicolletii" = Hoploscaphites nicolletii Morton 1842 ammonite
Scaphites sp. Parkinson 1811 ammonite
Reptilia
 Testudinata - Baenidae
Baenidae indet. Cope 1882 turtle
 Testudines - Trionychidae
Trionychinae indet. Gray 1825 softshell turtle
 Crocodylia - Crocodylidae
 Ornithischia - Ceratopsidae
cf. Triceratops sp. Marsh 1889 ceratopsid
 Ornithischia - Hadrosauridae
cf. Edmontosaurus sp. Lambe 1917 hadrosaurine
 Theropoda - Ornithomimidae
Ornithomimidae indet. Marsh 1890 ornithomimid
 Choristodera -
Champsosaurus sp. Cope 1876 choristodere
 Plesiosauria -
Plesiosauria indet. de Blainville 1835 plesiosaur