R-306 (Cambrian of the United States)

Also known as R-280c and R-305

Where: Weber County, Utah (41.3° N, 111.7° W: paleocoordinates 5.8° S, 90.5° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Ptychagnostus gibbus trilobite zone, Blacksmith Formation, Amgan (510.2 - 504.5 Ma)

• Topazan. 30.5 m above the base of the P. gibbus Zone & also 30.5 m above the top of a carbonate unit with capping lenses of bioclastic limestone that contain a distinctive "Glyphaspis fauna,"

• bed-level stratigraphic resolution

Environment/lithology: brown, gray claystone and bentonitic limestone

• Abundant agnostoid trilobites are in rare concretions with a matrix of dark-gray micritic limestone, and the concretions are scattered in light-brownish-gray unfossiliferous claystone.

Size class: macrofossils

Primary reference: R. A. Robison. 1978. Origin, taxonomy, and homeomorphs of Doryagnostus (Cambrian Trilobita). University of Kansas Paleontological Contributions 91:1-10 [P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 225065: authorized by Pete Wagner, entered by Pete Wagner on 21.04.2022

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Artiopoda
 Agnostida - Peronopsidae
Peronopsis fallax
Peronopsis fallax Linnarsson 1869
 Agnostida - Spinagnostidae
Doryagnostus wasatchensis n. sp.
Doryagnostus wasatchensis n. sp. Robison 1978
 Agnostida - Ptychagnostidae
"Ptychagnostus gibbus" = Triplagnostus gibbus, Ptychagnostus intermedius, Ptychagnostus seminula
"Ptychagnostus gibbus" = Triplagnostus gibbus Linnarsson 1869
Ptychagnostus seminula Whitehouse 1939
Trilobita
 Ptychopariida - Ptychopariidae
"Elrathina sp." = Ptychoparella
"Elrathina sp." = Ptychoparella Poulson 1927 trilobite