Greasewood Creek (Cretaceous of the United States)

Also known as SDSM V-685

Where: Niobrara County, Wyoming (43.3° N, 104.4° W: paleocoordinates 49.7° N, 79.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Lance Formation, Lancian (70.6 - 66.0 Ma)

• member-level stratigraphic resolution

Environment/lithology: fluvial; poorly lithified, gray sandstone

• "relatively high-energy aqueous environment... cross-bedding and scour features, suggest a fluvial origin"
• "yellowish-gray, well sorted and rounded, medium to coarse-grained quartz sandstone... usually friable"

Size classes: macrofossils, mesofossils

Reposited in the SDSM

Collection methods: surface (float)

• "surface prospecting" of a blowout

Primary reference: J. L. Whitmore and J. E. Martin. 1986. Vertebrate fossils from the Greasewood Creek locality in the Late Cretaceous Lance Formation of Niobrara County, Wyoming. Proceedings of the South Dakota Academy of Sciences 65:33-50 [J. Alroy/M. Sommers]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 14557: authorized by John Alroy, entered by John Alroy on 15.05.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Chondrichthyes
 Myliobatiformes - Dasyatidae
Myledaphus bipartitus Cope 1876 whiptail stingray
Actinopteri
 Acipenseriformes - Acipenseridae
Acipenser eruciferus Cope 1876 sturgeon
 Teleostei - Aspidorhynchidae
 Amiiformes - Amiidae
Amia fragosa Jordan 1927 bowfin
 Lepisosteiformes - Lepisosteidae
"Atractosteus occidentalis" = Lepisosteus occidentalis
"Atractosteus occidentalis" = Lepisosteus occidentalis Leidy 1856 gar
Osteichthyes
 Proteida - Batrachosauroididae
Opisthotriton kayi Auffenberg 1961 tetrapod
 Caudata - Urodela
Habrosaurus dilatus Gilmore 1928 siren
Scapherpeton tectum Cope 1876 salamander
Reptilia
 Testudines - Trionychidae
Trionychidae indet. Gray 1825 softshell turtle
 Testudines - Compsemydidae
Compsemys victa Leidy 1856 turtle
 Testudines - Baenidae
 Testudines - Pantrionychidae
 Avetheropoda -
Paronychodon lacustris Cope 1876 coelurosaur
 Avetheropoda - Tyrannosauridae
cf. Albertosaurus sp. Osborn 1905 Alberta lizard
 Neornithischia - Ceratopsidae
cf. Triceratops sp. Marsh 1889 ceratopsid
 Neornithischia - Thescelosauridae
cf. Thescelosaurus sp. Gilmore 1913 ornithischian
 Neornithischia - Hadrosauridae
cf. Edmontosaurus sp. Lambe 1917 hadrosaurine
 Crocodylia -
"Leidyosuchus sternbergi" = Borealosuchus sternbergii
"Leidyosuchus sternbergi" = Borealosuchus sternbergii Gilmore 1910 crocodilian
 Crocodylia - Crocodylidae
Crocodylidae indet. Cuvier 1807 crocodile
 Crocodylia - Alligatoridae
Brachychampsa montana Gilmore 1911 crocodilian
 Choristodera -
Champsosaurus sp. Cope 1876 choristodere
Mammalia
 Theriiformes - Peradectidae
"Pediomys cf. krejcii" = Leptalestes krejcii
"Pediomys cf. krejcii" = Leptalestes krejcii Clemens 1966 metatherian