Georgetown-Nounan Road (Triassic to of the United States)

Also known as IMNH 79002

Where: Bear Lake County, Idaho (42.5° N, 111.4° W: paleocoordinates 11.9° N, 35.3° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Thaynes Formation, Smithian to Smithian (251.3 - 247.2 Ma)

• "Smithian-Spathian.... The exact stratigraphic level is uncertain, but the material is most likely from below the Platy Siltstone Member" (i.e., in the Lower Black Shale Member)

Environment/lithology: terrestrial; poorly lithified, nodular, gray limestone

• most specimens preserve little or no matrix (suggesting lack of lithification) but "One specimen... appears to be in a small, gray limestone nodule"

Size class: macrofossils

Collected by H. G. MacDonald in 1985

Collection methods: surface (float),

• "recovered as surface float"

•IMNH collection

Primary reference: J. A. Massare and J. M. Callaway. 1994. Cymbospondylus (Ichthyosauria: Shastasauridae) from the Lower Triassic Thaynes Formation of southeastern Idaho. Journal of Vertebrate Paleontology 14(1):139-141 [J. Alroy/J. Alroy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 90338: authorized by John Alroy, entered by John Alroy on 16.07.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Ichthyosauria - Cymbospondylidae
Cymbospondylus sp. Leidy 1868 ichthyosaur