M. S. M. 72.51. Rolla (Ordovician of the United States)

Where: Phelps County, Missouri (38.6° N, 92.2° W: paleocoordinates 22.9° S, 78.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Rich Fountain Formation, Jeffersonian (485.4 - 470.0 Ma)

• Arengian half

• formation-level stratigraphic resolution

Environment/lithology: lithified, fine-grained, white, argillaceous, cherty/siliceous dolomite

• Massive to thin-bedded, white to buff to gray, fine grained argillaceous to coarsely crystalline dolomite.

Size class: macrofossils

Primary reference: J. S. Cullison. 1944. The stratigraphy of some Lower Ordovician formations of the Ozark uplift. University of Missouri School of Mines and Metallurgy Technical Series Bulletin 15(2):1-112 [P. Wagner/P. Wagner]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 56504: authorized by Pete Wagner, entered by Pete Wagner on 20.11.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

 Murchisoniina - Hormotomidae
Hormotoma dubia Donald 1899 snail
 Tryblidiida - Tryblidiidae
Proplina elongata n. sp. Cullison 1944
 Tarphycerida - Estonioceratidae
Aphetoceras ozarkensis n. sp. Cullison 1944
Aphetoceras subcostulatum Ulrich et al. 1942