Where: Montana (47.1° N, 109.4° W: paleocoordinates 18.4° N, 28.4° W)
• coordinate based on political unit
• basin-level geographic resolution
When: Upper Member (Shedhorn Formation), Wordian (266.9 - 264.3 Ma)
• member-level stratigraphic resolution
Environment/lithology: marine; sandstone
Primary reference: E. L. Yochelson and D. H. Van Sickle. 1968. Biostratigraphy of the Phosphoria, Park City, and Shedhorn Formations; Geology of Permian Rocks in the Western Phosphate Field. United States Geological Survey Professional Paper 313(D):572-660 [A. Miller/C. Ferguson/P. Wagner]more details
Purpose of describing collection: biostratigraphic analysis
PaleoDB collection 11276: authorized by Arnold Miller, entered by Chad Ferguson on 30.07.2001, edited by Pete Wagner
Creative Commons license: CC BY (attribution)
Taxonomic list
unclassified | |
Bivalvia | |
Nuculopsis poposiensis Branson 1930 nut clam | |
Schizodus sp. King 1844 clam
Schizodus cf. bifidus Ciriacks 1963 clam | |
"Costatoria sexradiata" = Procostatoria sexradiata
"Costatoria sexradiata" = Procostatoria sexradiata Branson 1930 clam | |
Pseudopermophorus annettae Ciriacks 1963 clam | |
Acanthopecten sp. Girty 1903 scallop | |
Aviculopecten sp. M'Coy 1851 scallop | |
"Aviculopecten cf. alternatus" = Cyrtorostra varicostata
"Aviculopecten cf. alternatus" = Cyrtorostra varicostata Branson 1930 scallop | |
Gastropoda | |
Bellerophontoidea indet. M'Coy 1851 snail | |
Bellerophon deflectus Chronic 1952 snail | |
"Euphemitopsis subpapillosus" = Euphemitopsis subpapillosa, Euphemitopsis cf. paucinodosus, Euphemites sp., Warthia sp.
"Euphemitopsis subpapillosus" = Euphemitopsis subpapillosa White 1876 snail
Euphemitopsis cf. paucinodosus Yochelson 1960 snail
Euphemites sp. Warthin 1930 snail
Warthia sp. Waagen 1880 snail | |
Scaphopoda | |
Plagioglypta sp. Pilsbry 1898 tusk shell | |
"Plagioglypta canna" = Prodentalium canna
"Plagioglypta canna" = Prodentalium canna White 1874 tusk shell | |
Strophomenata | |
aff. Echinauris sp. Muir-Wood and Cooper 1960 | |
Chonetes sp. Fischer de Waldheim 1830 | |
Derbyia sp. Waagen 1884 | |
Rhynchonellata | |
Wellerella sp. Dunbar and Condra 1932 | |
Composita sp. Brown 1849 | |
Lingulata | |
Lingula sp. BruguiƩre 1797 | |
Stenolaemata | |
| |
Gnathostomata | |
Osteichthyes indet. bony fish | |
unclassified | |
Porifera indet. Grant 1836 |