Sardeson Collection, Dunleith Formation, Mortimer 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: Belodina confluens conodont zone, Mortimer Member (Dunleith Formation), Shermanian (460.9 - 449.5 Ma)

• member-level stratigraphic resolution

Environment/lithology: limestone

• Environmental call by T. Hanson.
• Limestone, sometimes dolomitic. Lithology from C. O. Leverson, A. J. Gerk, R. E. Sloan, & L. A. Bisagno. General section of the Middle and Late Ordovician strata of Northeastern Iowa, Middle and Late Ordovician lithostratigraphy and biostratigraphy of the Upper Mississippi Valley: Minnesota Geological Survey Report of Investigations 35, p.25-39. Edited by R. E. Sloan.

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 23802: authorized by Steven Holland, entered by Tori Hanson on 21.07.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Trilobita
 Corynexochida - Illaenidae
Bumastus orbicaudatus Billings 1859 trilobite
Illaenus sp. Dalman 1827 trilobite
 Phacopida - Encrinuridae
"Encrinuroides vigilans" = Erratencrinurus vigilans
"Encrinuroides vigilans" = Erratencrinurus vigilans Hall 1847 trilobite
 Phacopida - Calymenidae
Flexicalymene senaria Conrad 1841 trilobite
Strophomenata
 Billingsellida - Clitambonitidae
 Strophomenida - Sowerbyellidae
 Strophomenida - Rafinesquinidae
 Strophomenida - Strophomenidae
"Strophomena trilobita" = Strophomena trilobata Owen 1852
Strophomena billingsi Winchell and Schuchert 1893
Furcitella scofieldi Winchell and Schuchert 1892
Rhynchonellata
 Pentamerida - Parastrophinidae
 Atrypida - Cyclospiridae
 Atrypida - Anazygidae
 Rhynchonellida - Rhynchotrematidae
 Orthida - Draboviidae
 Orthida - Glyptorthidae
 Orthida - Hesperorthidae
 Orthida - Platystrophiidae
 Orthida - Plectorthidae
Lingulata
 Lingulida - Pseudolingulidae