Sardeson Collection, Ion Formation, St. James Member, Illinois and Iowa (Ordovician of the United States)

Where: Illinois, Iowa (42.0° N, 90.5° W: paleocoordinates 21.3° S, 63.6° W)

• coordinate estimated from map

• basin-level geographic resolution

When: St. James Member (Ion Formation), Kirkfieldian (460.9 - 449.5 Ma)

• member-level stratigraphic resolution

Environment/lithology: shale

• 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, R. E. Sloan, ed.

Size class: macrofossils

Primary reference: J. A. Catalani. 1987. Biostratigraphy of the Middle and Late Ordovician cephalopods of the Upper Mississippi Valley area. Middle and Late Ordovician lithostratigraphy and biostratigraphy of the Upper Mississippi Valley: Minnesota Geological Survey Report of Investigations 35 187-189 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 23798: authorized by Steven Holland, entered by Tori Hanson on 21.07.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Trilobita
 Phacopida - Pterygometopidae
Sceptaspis lincolnensis Branson 1909 trilobite
 Asaphida - Asaphidae
Isotelus gigas Dekay 1824 trilobite
Strophomenata
 Strophomenida - Sowerbyellidae
 Strophomenida - Rafinesquinidae
 Strophomenida - Strophomenidae
Strophomena septata Winchell and Schuchert 1892
Oepikina minnesotensis Winchell 1881
Rhynchonellata
 Protorthida - Skenidiidae
 Atrypida - Anazygidae
"Zygospira recurvirostris" = Anazyga recurvirostra
"Zygospira recurvirostris" = Anazyga recurvirostra Hall 1847
 Rhynchonellida - Trigonirhynchiidae
 Rhynchonellida - Rhynchotrematidae
 Orthida - Draboviidae
 Orthida - Dalmanellidae
 Orthida - Glyptorthidae
 Orthida - Plaesiomyidae
"Plaesiomys meedsi" = Dinorthis meedsi
"Plaesiomys meedsi" = Dinorthis meedsi Winchell and Schuchert 1892
 Orthida - Hesperorthidae
 Orthida - Platystrophiidae
Lingulata
 Lingulida - Pseudolingulidae
Craniata
 Craniida - Craniidae
Acanthocrania setigeria
[entered as Acanthocrania setigera]