Geiser Quarry, 2.1 km east of Dutchtown. Unit 2 (Ordovician of the United States)

Also known as Klapper & Bergström locality 1

Where: Cape Girardeau County, Missouri (37.3° N, 89.6° W: paleocoordinates 25.5° S, 76.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Middle Member (Dutchtown Formation), Cassinian (478.6 - 468.1 Ma)

• lowest beds of Middle member. N. American Conodont zone 5 (middle Whiterockian)

• group of beds-level stratigraphic resolution

Environment/lithology: limestone

• Limestone, dark-blue to brown, dense to finely crystalline, and slightly granular in upper portion. Limestone conglomerate of shingle type occurs near the base.

Size class: macrofossils

Preservation: replaced with silica

Collection methods: bulk, hydrochloric

• Missouri School of Mines and Mineralogy

Primary reference: M. F. Fix. 1975. The Paleontology and stratigraphy of the Smithville and Blackrock Formations of Southeastern Missouri. M.S. Thesis, Geology, Washington University 1-147 [P. Wagner/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 75553: authorized by Pete Wagner, entered by Pete Wagner on 16.10.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

Ostracoda
 Leperditicopida - Leperditiidae
Isochilina variana n. sp. Cullison 1938 ostracod
Bivalvia
 Modiomorphida - Allodesmatidae
Ischyrodonta dakei n. sp. Cullison 1938 clam
 Modiomorphida - Modiomorphidae
Modiolopsis convexa n. sp. Cullison 1938 clam
Gastropoda
 Murchisoniina - Straparollinidae
"Lophospira corrugata n. sp." = Straparollina cassina, "Lophospira dutchtownensis n. sp." = Straparollina cassina
"Lophospira corrugata n. sp." = Straparollina cassina Whitfield 1886 snail
"Lophospira dutchtownensis n. sp." = Straparollina cassina Whitfield 1886 snail
Stenolaemata
 Cystoporata - Ceramoporidae
Crepipora globulifera n. sp. Cullison 1938
Conodonta
  - Archaeognathidae
? Archeognathus carinatus n. sp. Cullison 1938 conodont