West flank of Big Horn Mountains (Jurassic of the United States)

Where: Bighorn County, Wyoming (44.7° N, 107.8° W: paleocoordinates 35.8° N, 47.6° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Gypsum Spring Formation, Late/Upper Bajocian (171.6 - 167.7 Ma)

• Middle unit of the Gypsum Spring Formation. The ammonites Parachondroceras sp. and Sohlites sp. have been reported from the middle part of the Gypsum Spring Formation on the western side of the Bighorn Basin. These species imply a probable age of late Bajocian for that part of the formation.

• group of beds-level stratigraphic resolution

Environment/lithology: open shallow subtidal; lithified limestone

• warm, shallow marine environment with near normal salinities. Skeletal fragments and ooids were concentrated during normal wave action as well as during occasional storms. Thin stringers of gypsum and stromatolitic carbonate layers indicate local periods of increased salinity.

Size class: macrofossils

Reposited in the USNM

Collection methods: mechanical,

Primary reference: G. S. Guyer, C. E. Schweitzer, and R. M. Feldmann. 2014. First record of decapod crustaceans (Astacidea, Stenochiridae) from the Gypsum Springs Formation (Jurassic) of Wyoming, USA. Bulletin of the Mizunami Fossil Museum 40:1-11 [C. Schweitzer/C. Schweitzer]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 155766: authorized by Carrie Schweitzer, entered by Carrie Schweitzer on 30.04.2014

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Malacostraca
 Decapoda - Stenochiridae
Gracilimanus obscurus n. gen. n. sp., Gypsonicus wyomingensis n. gen. n. sp.
Gracilimanus obscurus n. gen. n. sp. Feldmann and Schweitzer 2014 decapod
Gypsonicus wyomingensis n. gen. n. sp. Schweitzer and Feldmann 2014 decapod