Eucalyptocrinites-Crotalocrinites-Caryocrinites Association of the Racine Format (Silurian of the United States)

Also known as Reef 3169

Where: Waukesha County County, Wisconsin (43.0° N, 88.4° W: paleocoordinates 23.5° S, 51.2° W)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Racine Formation, Wenlock (433.4 - 427.4 Ma)

• Lower-middle Racine Formation, probably mid-Wenlockian.

Environment/lithology: reef, buildup or bioherm; lithified dolomite and lithified, dolomitic lime mudstone

• Very fossiliferous. This is a typical Wenlockian carbonate mud mound community, in which the core contains mostly carbonate mud, sometimes with Stromatactis-like structures, and echinoderm debris and the flank beds are echinoderm-dominated. Skeletal grains in the flank beds which contain this community can be either moldic or dolomite-replaced, and the texture ranges from non-cherty, porous dolowackestone to dolopackstone, with some grainstone present also in the flank facies, to crystalline dolomudstones and sparse dolowaxkestone to dolopackstone, with some grainstone present also in the flank facies, to crystalline dolomudstones and sparse dolowackestones in the cores. Skeletal grains show the full range from well to poorly sorted, and some graded bedding is present in the inclined beds of the echinoderm facies. Corals, which tend to surround the mound core, are sometimes overturned (Philcox, 1970), and in any case, are not abundant enough to form an organic framework. As noted by Witzke (1981b, 1987b), the general absence of skeletal boundstone fabrics precludes interpretation as an organic-framework reef, but the presence of apparent penecontemporaneous cave and fissure-fills in the core, often with thick trilobite or nautiloid concentrations, plus wedge-shaped debris flows in some facies, suggests that the mounds were rigid features, possibly resulting from submarine cementation processes (Witzke, 1987a). Dolomitized botryoidal and fibrous marine cembents are present. Sedimentary features are consistent with episodic high-energy conditions, such as would result from storm action in depths generally at or slightly below fair weather wave base.

Preservation: replaced with dolomite

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 13353: authorized by Michael Foote, entered by Kimberly Koverman on 04.03.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

unclassified
  -
Chlorophyceae
  - Receptaculitidae
Ischadites sp. Eichwald 1861
Anthozoa
 Stauriida - Hapsiphyllidae
 Stauriida - Zaphrentidae
Zaphrentidae indet. Milne-Edwards and Haime 1850 horn coral
 Cystiphyllida - Cystiphyllidae
 Heliolitida - Halysitidae
Halysites sp. von Waldheim 1813 tabulate coral
 Heliolitida - Heliolitidae
Heliolites sp. Dana 1846 tabulate coral
 Favositida - Favositidae
Favosites sp. Lamarck 1816 tabulate coral
 Favositida - Alveolitidae
Alveolites sp. Lamarck 1801 tabulate coral
Cephalopoda
 Nautiloidea -
Nautiloidea indet. Agassiz 1847 nautiloid
Gastropoda
 Murchisoniina - Trochonematidae
? Trochonema sp. Salter 1859 snail
 Euomphalina - Platyceratidae
Platyceras sp. Conrad 1840 snail
Bivalvia
 Cyrtodontida - Cyrtodontidae
Cyrtodonta sp. Billings 1858 clam
 Myalinida - Ambonychiidae
"Plethomytilus sp." = Mytilarca
"Plethomytilus sp." = Mytilarca Hall and Whitfield 1869 clam
 Ostreida - Pterineidae
Leptodesma sp. Hall 1883 oyster
Strophomenata
 Orthotetida - Chilidiopsidae
"Coolinia sp." = Fardenia (Coolinia)
"Coolinia sp." = Fardenia (Coolinia) Bancroft 1949
 Strophomenida - Sowerbyellidae
Eoplectodonta sp. Kozlowski 1929
 Strophomenida - Strophodontidae
"Protomegastrophia profunda" = Brachyprion (Protomegastrophia) profunda
"Protomegastrophia profunda" = Brachyprion (Protomegastrophia) profunda Hall 1852
 Strophomenida - Rafinesquinidae
Leptaena rhomboidalis Wahlenberg 1818
Rhynchonellata
 Rhynchonellida - Rhynchotrematidae
aff. Stegerhynchus sp. Foerste 1909
Rhynchonellid aff. Stegerhynchus
 Rhynchonellida - Trigonirhynchiidae
Rhynchotreta sp. Hall 1879
 Rhynchonellida - Uncinulidae
Uncinulidae indet. Rzonsnitzkaja 1956
 Orthida - Orthidae
Orthidae indet. Woodward 1852
 Orthida - Hesperorthidae
Dolerorthis sp. Schuchert and Cooper 1931
 Orthida - Platystrophiidae
"Platystrophia biforata" = Platystrophia biforatus
"Platystrophia biforata" = Platystrophia biforatus Schlotheim 1820
 Orthida - Dalmanellidae
Resserella sp. Bancroft 1928
 Atrypida - Atrypidae
Plectatrypa sp. Schuchert and Cooper 1930
Atrypa ? reticularis Linnaeus 1758
Atrypa 'reticularis'
 Pentamerida - Gypidulidae
Gypidulidae sp. Schuchert and Le Vene 1929
 Pentamerida - Pentameridae
"Apopentamerus sp." = Harpidium (Isovella)
"Apopentamerus sp." = Harpidium (Isovella) Breyvel and Breyvel 1970
 Spiriferida - Cyrtiidae
Hedeina sp. Boucot 1957
Eospirifer sp. Schuchert 1913
Stenolaemata
 Cryptostomata - Fenestellidae
Trilobita
 Corynexochida - Illaenidae
Bumastus sp. Murchison 1839 trilobite
 Phacopida - Cheiruridae
Sphaerexochus romingeri Hall 1868 trilobite
Crinoidea
  -
Crinoidea indet. Miller 1821 Sea lily
 Monobathrida - Periechocrinidae
Periechocrinus sp. Morris 1843 Sea lily
 Monobathrida - Patelliocrinidae
 Monobathrida - Eucalyptocrinitidae
 Diplobathrida - Lampterocrinidae
 Diplobathrida - Dimerocrinitidae
Dimerocrinites sp. Phillips 1839 Sea lily
 Sagenocrinida - Lecanocrinidae
 Cyathocrinida - Crotalocrinitidae
 Cyathocrinida - Cyathocrinitidae
? Cyathocrinites vanhornei Sea lily
'Cyathocrinites' vanhornei
 Myelodactylida - Myelodactylidae
Myelodactylus sp. Hall 1852 Sea lily
Rhombifera
 Hemicosmitoida - Caryocrinitidae
 Sphaeronitida - Holocystitidae
Blastoidea
  -