Locality M-4. north of abandoned YMCA Camp Rivercliff near the crest of the hill ( of the United States)

Also known as Locality M-4, Gasconade Formation, Crawford County, Missouri - Stinchcomb 1986

Where: Crawford County, Missouri (37.9° N, 91.2° W: paleocoordinates 23.5° S, 81.0° W)

• outcrop-level geographic resolution

When: Ophileta zone, Gasconade Formation, Tremadoc (486.5 - 477.7 Ma)

• The Van Buren Formation (Bridge 1930) is now referred to in an interval sense with the Van Buren fauna comprising a zone in the lowerpart of the Gasconade Formation. The chert in which the fossils occur may or may not be in place stratigraphically. So, a rating of "A" through "F" indicates stratigraphic reliability with "A" = no question to stratigraphic position of horizon and "F" = residual material of different ages. Reliability Index = E

• formation-level stratigraphic resolution

Environment/lithology: reef, buildup or bioherm; lithified chert

• Strata are in pockets of the Ozark Uplifts
• chert masses and granular chert

Size classes: macrofossils, mesofossils

Preservation: original calcite, replaced with silica

Collection methods: Taxonomic list does not include stromatolites in which specimens were found.

Primary reference: B. L. Stinchcomb. 1986. New Monoplacophora (Mollusca) from Late Cambrian and Early Ordovician of Missouri. Journal of Paleontology 60(3):606-626 [M. Patzkowsky/P. Borkow/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 8940: authorized by Mark Patzkowsky, entered by Phil Borkow on 07.09.2000, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Ellesmerocerida - Ellesmeroceratidae
Tergomya
 Tryblidiida - Proplinidae
Titanoplina meramecensis1 Stinchcomb and Angeli 2002
 Kiringellida -
Gastropoda
 Eogastropoda - Sinuopeidae
Schizopea typica3, "Sinuopea regalis" = Sinuopea sweeti2
Schizopea typica3 Ulrich et al. 1931 snail
"Sinuopea regalis" = Sinuopea sweeti2 Whitfield 1882 snail
Polyplacophora
 Paleoloricata - Mattheviidae
Hemithecella expansa2 Butts 1941 chiton
Hemithecella abrupta2 Stinchcomb and Darrough 1995 chiton