Sardeson Collection, Maquoketa Formation, Elgin Member (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: Amplexograptus manitoulinensis graptolite zone, Elgin Member (Scales Shale Formation), Edenian to Edenian (451.0 - 449.6 Ma)

• Beds numbered by F. W. Sardeson.

• group of beds-level stratigraphic resolution

Environment/lithology: shale and limestone

• Environmental call by T. Hanson.
• Shale interbedded with limestone; sometimes dolomitic. Lithology from F. M. Swain. 1987. Middle and Upper Ordovician Ostracoda of Minnesota and Iowa. Middle and Late Ordovician lithostratigraphy and biostratigraphy of the Upper Mississippi Valley: Minnesota Geological Survey Report of Investigations 35 :99-101.

Size class: macrofossils

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 23282: authorized by Steven Holland, entered by Tori Hanson on 11.07.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Lingulata
 Lingulida - Pseudolingulidae
? Pseudolingula iowensis
 Lingulida - Lingulasmatidae
"Lingula philomela" = Lingulasma philomela
"Lingula philomela" = Lingulasma philomela Billings 1865
"Lingula" philomela
 Lingulida - Obolidae
Lingulops sp.
Lingulops sp. Hall 1871
 Lingulida - Discinidae
Orbiculoidea pelopea
Strophomenata
 Orthotetida - Triplesiidae
Oxoplecia ulrichi
 Strophomenida - Sowerbyellidae
Eoplectodonta saxea, Sowerbyella minnesotensis, "Eoplectodonta recedens" = Thaerodonta recedens
"Eoplectodonta recedens" = Thaerodonta recedens Sardeson 1892
 Strophomenida - Furcitellidae
Megamyonia unicostata
Megamyonia unicostata Meek and Worthen 1868
 Strophomenida - Strophomenidae
Tetraphalerella planodorsata, "Strophomena trilobita" = Strophomena trilobata, Strophomena occidentalis, "Strophomena cf. fluctuosa" = Nasutimena fluctuosa
Tetraphalerella planodorsata Winchell and Schuchert 1892
"Strophomena trilobita" = Strophomena trilobata Owen 1852
"Strophomena cf. fluctuosa" = Nasutimena fluctuosa Billings 1860
 Strophomenida - Rafinesquinidae
Rafinesquina nitans, Rafinesquina trentonensis, Rafinesquina deltoidea
Rhynchonellata
 Atrypida - Anazygidae
Zygospira modesta
 Rhynchonellida - Rhynchotrematidae
Hypsiptycha anticostiensis, "Lepidocyclus capax" = Hiscobeccus capax
"Lepidocyclus capax" = Hiscobeccus capax Conrad 1842
 Orthida - Heterorthidae
"? Eremotrema emacerata" = Heterorthina emacerata
"? Eremotrema emacerata" = Heterorthina emacerata Hall 1860
 Orthida - Dalmanellidae
? Onniella porrecta, Paucicrura corpulenta
Paucicrura corpulenta Sardeson 1892
 Orthida - Platyorthidae
Diceromyonia ignota
 Orthida - Plaesiomyidae
"Plaesiomys meedsi" = Dinorthis meedsi, "Plaesiomys subquadrata" = Plaesiomys subquadratus, Plaesiomys proavita, Austinella kankakensis
"Plaesiomys meedsi" = Dinorthis meedsi Winchell and Schuchert 1892
"Plaesiomys subquadrata" = Plaesiomys subquadratus Hall 1847
Plaesiomys proavita Winchell and Schuchert 1892
Austinella kankakensis McChesney 1861
 Orthida - Glyptorthidae
Glyptorthis insculpta, Glyptorthis bellarugosa
 Orthida - Plectorthidae
Hebertella occidentalis
Trilobita
 Corynexochida - Illaenidae
Bumastus orbicaudatus
Bumastus orbicaudatus Billings 1859 trilobite
 Phacopida - Calymenidae
"Flexicalymene senaria" = Flexicalymene (Flexicalymene) senaria, "Calymene mamillate" = Thelecalymene mammillata, Calymene winchelli
"Flexicalymene senaria" = Flexicalymene (Flexicalymene) senaria Conrad 1841 trilobite
"Calymene mamillate" = Thelecalymene mammillata Hall 1861 trilobite
 Phacopida - Pterygometopidae
Eomonorachus intermedius
Eomonorachus intermedius Walcott 1879 trilobite
 Phacopida - Encrinuridae
"Encrinuroides vigilans" = Erratencrinurus vigilans
"Encrinuroides vigilans" = Erratencrinurus vigilans Hall 1847 trilobite
 Phacopida - Cheiruridae
Ceraurinus icarus, Ceraurus pleurexanthemus
Ceraurinus icarus Billings 1860 trilobite
Ceraurus pleurexanthemus Green 1832 trilobite
 Asaphida - Asaphidae
Isotelus gigas, Isotelus susae, Isotelus iowensis
Isotelus gigas Dekay 1824 trilobite
Isotelus susae Whitfield 1882 trilobite
Isotelus iowensis Owen 1852 trilobite