Sardeson Collection, Platteville Formation (Ordovician to of the United States)

Where: Minnesota (45.0° N, 93.3° W: paleocoordinates 17.8° S, 62.8° W)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Platteville Formation, Blackriveran to Blackriveran (460.9 - 449.5 Ma)

• Beds numbered by F. W. Sardeson.

• group of beds-level stratigraphic resolution

Environment/lithology: limestone

• Environmental call by T. Hanson
• Limestone with shaly partings.

Size class: macrofossils

Preservation: cast, replaced with dolomite

Primary reference: W. F. Rice and E. P. Hedblom. 1987. Brachiopods and trilobites of the Sardeson Beds in the Twin Cities. Middle and Late Ordovician lithostratigraphy and biostratigraphy of the Upper Mississippi Valley: Minnesota Geological Survey Report of Investigations 35 131-135 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 23276: authorized by Steven Holland, entered by Tori Hanson on 11.07.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

 Corynexochida - Illaenidae
Illaenus sp. Dalman 1827 trilobite
Thaleops ovata Conrad 1843 trilobite
Bumastoides milleri Billings 1859 trilobite
 Phacopida - Pterygometopidae
Sceptaspis lincolnensis Branson 1909 trilobite
 Phacopida - Cheiruridae
 Proetida - Bathyuridae
"Raymondites longispinus" = Bathyurus (Raymondites) longispinus
"Raymondites longispinus" = Bathyurus (Raymondites) longispinus Walcott 1876 trilobite
 Asaphida - Asaphidae
Isotelus simplex, "Basiliella barrandi" = Basilicus (Basiliella)
"Basiliella barrandi" = Basilicus (Basiliella) trilobite
 Lichida - Lichidae
Amphilichas sp. Raymond 1905 trilobite
 Strophomenida - Strophomenidae
Trigrammaria winchelli Hall and Clarke 1892
Oepikina minnesotensis Winchell 1881
 Protorthida - Skenidiidae
 Atrypida - Protozygidae
"Protozyga nicolleti" = Manespira nicolleti
"Protozyga nicolleti" = Manespira nicolleti Winchell and Schuchert 1892
 Rhynchonellida - Trigonirhynchiidae
 Orthida - Glyptorthidae
 Orthida - Plaesiomyidae
 Orthida - Hesperorthidae
 Orthida - Plectorthidae
 Lingulida - Trematidae
Trematis huronensis Billings 1865
 Lingulida - Disciniidae
 Lingulida - Pseudolingulidae
 Lingulida - Obolidae
 Siphonotretida - Siphonotretidae
Schizambon sp. Walcott 1884
 Craniida - Craniidae