Hesperorthis-Eoleperditia community (Ordovician of the United States)

Also known as Mifflin Submember, Platteville Fm, SW Wisconsin, Hesperorthis-Eoleperditia

Where: Wisconsin (42.7° N, 90.5° W: paleocoordinates 20.8° S, 63.1° W)

• coordinate estimated from map

When: Mifflin Member (McGregor Formation), Caradoc (458.4 - 449.5 Ma)

• Was: McGregor Member (Platteville Formation), Mifflin Submember

• member-level stratigraphic resolution

Environment/lithology: deep subtidal; mudstone and packstone

• pelletal mudstone-packstone approximately 10 m thick. Fossils were collected from coquinas.

Size class: macrofossils

Primary reference: C. W. Byers and S. Gavlin. 1979. Two contemporaneous equilibrium communities in the Ordovician of Wisconsin. Lethaia 12:297-305 [M. Patzkowsky/Z. Krug]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 55472: authorized by Mark Patzkowsky, entered by Zack Krug on 26.10.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

Ostracoda
 Leperditicopida - Leperditiidae
Eoleperditia sp. Swartz 1949 ostracod
Trilobita
 Corynexochida - Illaenidae
Illaenus sp. Dalman 1827 trilobite
Bumastus sp. Murchison 1839 trilobite
 Phacopida - Encrinuridae
Encrinurus sp. Emmrich 1844 trilobite
 Phacopida - Cheiruridae
Ceraurus sp. Green 1832 trilobite
Gastropoda
 Murchisoniina - Eotomariidae
Liospira sp. Ulrich and Scofield 1897 snail
 Bellerophontida - Sinuitidae
Sinuites sp. Koken 1896 snail
 Bellerophontida - Bucaniidae
Phragmolites sp. Conrad 1838 snail
Rhynchonellata
 Rhynchonellida - Rhynchotrematidae
Rhynchotrema sp. Hall 1860
 Orthida - Hesperorthidae
Hesperorthis sp. Schuchert and Cooper 1931
 Orthida - Plaesiomyidae
Dinorthis sp. Hall and Clarke 1892
Campylorthis sp. Ulrich and Copper 1942
 Orthida - Draboviidae
Pionodema sp. Foerste 1912
 Orthida - Dalmanellidae
Onniella sp. Bancroft 1928
Strophomenata
 Strophomenida - Rafinesquinidae
Rafinesquina sp. Hall and Clarke 1892
 Strophomenida - Strophomenidae
Strophomena sp. Rafinesque and De Blainville 1824
Opikina sp. Salmon 1942