Petalocrinus longus-Zophocrinus howardi Assoc., Laurel Member, SE Indiana (Silurian of the United States)

Where: Indiana (39.4° N, 85.6° W: paleocoordinates 27.6° S, 51.6° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Laurel Member (Salamonie Dolomite Formation), Wenlock (433.4 - 427.4 Ma)

• "Middle WEnlockian [based on correlation with Kockelella amsdeni Zone in Tennesse (in which Laurel is upper part of Maddox Member, Wayne Formation]..."

• member-level stratigraphic resolution

Environment/lithology: deep subtidal; bioturbated, shelly/skeletal grainstone and bioturbated, shelly/skeletal packstone

• "[echinoderms mostly isolated plates]...little evidence of regular current action, although some winnowed debris piles are found...thin sections show mottled and swirled texture typical of burrowed and biogenically reworked sediments..Frest and Strimple ('77b) comment on prevalence of [crinoids] with planar arm fans...as representing quiet offshore (below normal wave base) environment with relatively slow rate of sediment accumulation. A BA3-4 boundary position seems likely from the echinoderms"

•

•SEP environmental call based on given information and knowledge of regional geology

• "Very fossiliferous...The usual lithology is echinoderm grainstone, with secondary echinoderm packstone.."

Primary reference: T. J. Frest, C. E. Brett, and B. J. Witzke. 1999. Caradocian-Gedinnian echinoderm associations of Central and Eastern North America. Paleocommunities--a case study from the Silurian and Lower Devonian 638-783 [M. Foote/K. Koverman/P. Wagner]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 26811: authorized by Michael Foote, entered by Michael Foote on 04.11.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Trilobita
 Phacopida - Calymenidae
Calymenidae indet.
Calymenidae indet. Milne-Edwards 1840 trilobite
 Corynexochida - Illaenidae
Stenopareia sp.
Stenopareia sp. Holm 1886 trilobite
Rhynchonellata
 Athyridida - Meristidae
Merista sp.
Merista sp. Suess 1851
 Atrypida - Atrypidae
Atrypa sp.
Atrypa sp. Dalman 1828
 Pentamerida - Clorindidae
Antirhynchonella sp.
Antirhynchonella sp. Oehlert 1887
Bryozoa
  -
Bryozoa indet.
Bryozoa indet. Ehrenberg 1831
Crinoidea
 Cyathocrinida - Petalocrinidae
Petalocrinus longus, Petalocrinus inferior
 Cyathocrinida - Thalamocrinidae
Thalamocrinus sp.
Thalamocrinus sp. Miller and Gurley 1895 Sea lily
 Pisocrinida - Pisocrinidae
Pisocrinus spp.
Pisocrinus spp. de Koninck 1858 Sea lily
 Disparida - Zophocrinidae
Zophocrinus howardi
 Diplobathrida - Dimerocrinitidae
Cyphocrinus gorbyi
 Monobathrida - Hirneacrinidae
Hirneacrinus cupellaeformis, Hirneacrinus perplanus
Hirneacrinus cupellaeformis Frest and Strimple 1977 Sea lily
Hirneacrinus perplanus Frest and Strimple 1977 Sea lily
 Sphaeronitida - Holocystitidae
Holocystites (Holocystites) alternatus
Cyclocystoidea
  - Cyclocystoididae
Sievertsia sp., Polytryphocycloides sp.
Sievertsia sp. Smith and Paul 1982
Polytryphocycloides sp. Smith and Paul 1982
Anthozoa
  -
Anthozoa indet.
Anthozoa indet. Ehrenberg 1834
unclassified
  -
Porifera indet.
Porifera indet. Grant 1836
Heteractinida
 Octactinellida - Astraeospongiidae
Astraeospongium sp.
Astraeospongium sp. Roemer 1860