Brachiopods of Rock Grove Mbr., Shell Rock Fm., North-Central Iowa (Devonian of the United States)

Where: Iowa (43.3° N, 92.8° W)

• Paleocoordinates: 26.1° S, 54.9° W (Wright 2013)

• coordinate based on political unit

• basin-level geographic resolution

When: Rock Grove Member (Shell Rock Formation), Frasnian (382.7 - 372.2 Ma)

• Within Strophodonta cicatricosa zone. Shell Rock as a whole is early-middle Frasnian.

• member-level stratigraphic resolution

Environment/lithology: marine; peloidal, shelly/skeletal, argillaceous limestone and peloidal, shelly/skeletal dolomite

• Witzke et al. (ref. 9582): mainly shallow subtidal.
• From Witzke et al. (PBDB ref. 9582): "..dominated by pelleted to skeletal limestone and dolomite, in part vuggy, and is poorly fossiliferous through much of its lower interval. Crossbedded calcarenites occur locally in the upper beds. The member includes shales and burrowed shaly limestones in the type area. Rock Grove strata incorporate laminated, intraclastic, brecciated, mudcracked, and "birdseye" bearing lithologies, especially in the lower half, to the W and SW..."

Collection methods: Fauna of the Shell Rock not reported here include mollusks, corals, stromatoporoids, and echinoderms. These elements usually dominate the assemblages.

Primary reference: J. Day. 1988. The brachiopod succession of the Late Givetian-Frasnian of Iowa. In N. J. McMillan, A. F. Embry, and D. J. Glass (eds.), Devonian of the World, Volume III. Canadian Society of Petroleum Geologists. Calgary, Alberta, Canada 303-325 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 35494: authorized by Michael Foote, entered by Michael Foote on 17.12.2003

Creative Commons license: CC0 (CC0)

Taxonomic list

Show authors, comments, and common names
Strophomenata
 Orthotetida - Areostrophiidae
Floweria sp.
Floweria sp. Cooper and Dutro 1982
F. n. sp.
 Strophomenida - Strophodontidae
Strophodonta (Strophodonta) cicatricosa, Strophodonta (Strophodonta) "n. sp. A"
Rhynchonellata
 Rhynchonellida - Hypothyridinidae
Lorangerella gregaria
 Rhynchonellida - Stenoscismatidae
Atribonium paupera, Atribonium nora
Atribonium paupera Grabau 1936
Atribonium nora Belanski 1928
 Orthida - Schizophoriidae
Schizophoria floydensis
 Spiriferida - Adolfiidae
Allanella cardinalis
 Spiriferida - Cyrtospiriferidae
Tenticospirifer shellrockensis
 Spiriferida - Spinocyrtiidae
Platyrachella ballardi
 Spiriferinida - Cyrtinidae
Cyrtina sp.
Cyrtina sp. Davidson 1858
C. n. sp.
 Athyridida - Athyrididae
Athyris aff. vittata
 Pentamerida - Gypidulidae
Gypidula papyracea
 Atrypida - Atrypidae
Spinatrypina sp., Pseudoatrypa aff. devoniana
Spinatrypina sp. Rzhonsnitskaya 1964
S. n. sp.
Craniata
 Craniida - Craniidae
Petrocrania famelica
Petrocrania famelica Hall and Whitfield 1872