Basal Maquoketa fm., basal Richmondian (Ordovician of the United States)

Where: Iowa (42.0° N, 91.6° W: paleocoordinates 20.1° S, 60.7° W)

• coordinate based on political unit

• basin-level geographic resolution

When: basal Member (Maquoketa Formation), Richmondian (449.6 - 445.5 Ma)

• "U. Ord. basal Richmondian, basal Maquoketa (above unconformity)"

Environment/lithology: shallow subtidal; phosphatic, silty dolomite

• "clayey and silty dolomite with phosphate, broad shallow epeiric sea, fluctuating salinity and O2. BA1 probably flooding s[illeg.]-deep BA5-6. craton."

Size class: macrofossils

Primary reference: P. W. Bretsky and J. J. Bermingham. 1970. Ecology of the Paleozoic scaphopod genera Plagioglypta with special reference to the Ordovician of eastern Iowa. Journal of Paleontology 44:908-924 [M. Uhen/J. Ju/M. Uhen]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 356: authorized by Jack Sepkoski, entered by Mike Sommers on 20.11.1998, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

• W.B. Harrison III and L.K. Harrison, 1975. A Maquoketa-like molluscan community in the Brassfield Fm. (early Silurian) of Adams Co., OH. Bull. Amer. Paleo. 67:193-23[illeg.] P.W. Bretsky and J.J. Bermingham, 1970. Ecology off the Paleozoic scaphopo[illeg.] gn. Plagioglypta with special reference to the Ord of eastern Iowa. J. Paleo. 44:908-924. Yochelson 1978 argues Plagioglypta (?) is Coleolus (= ? polychaeta)"
Show authors, comments, and common names
unclassified
  -
Buranella sp.
Scaphopoda
 Dentaliida - Dentaliidae
? Plagioglypta sp.
? Plagioglypta sp. tusk shell
originally entered as "? Plagioglypta sp."
Hyolitha
 Hyolithida - Hyolithidae
Hyolithes sp.
Hyolithes sp. d'Eichwald 1840
Lingulata
 Lingulida - Obolidae
Leptobolus sp.
Leptobolus sp. Hall 1871
Gastropoda
 Bellerophontida -
Bellerophontoidea indet.
Bellerophontoidea indet. M'Coy 1851 snail
 Bellerophontida - Tropidodiscidae
Tropidodiscus sp.
Tropidodiscus sp. Meek and Worthen 1866 snail
 Euomphalina - Holopeidae
Holopea sp., Raphistomina sp., Cyclora sp.
Holopea sp. Hall 1847 snail
Raphistomina sp. Ulrich and Scofield 1897 snail
Cyclora sp. Hall 1845 snail
 Euomphalina - Platyceratidae
Cyclonema sp.
Cyclonema sp. Hall 1852 snail
 Murchisoniina - Hormotomidae
Hormotoma sp.
Hormotoma sp. Salter 1859 snail
originally Murchisonia; PJW3
 Murchisoniina - Lophospiridae
Paupospira sp.
Paupospira sp. Wagner 1999 snail
originally Loxoplocus; PJW3
 Murchisoniina - Eotomariidae
Liospira sp.
Liospira sp. Ulrich and Scofield 1897 snail
Polyplacophora
 Paleoloricata -
Septemchiton sp.
Cephalopoda
 Orthocerida - Orthoceratidae
Michelinoceras sp.
Michelinoceras sp. Foerste 1932
Tergomya
 Cyrtonellida - Cyrtolitidae
Cyrtolites sp.
Cyrtolites sp. Conrad 1838
Bivalvia
 Modiomorphida - Modiomorphidae
Orthodesma sp.
Orthodesma sp. Hall and Whitfield 1875 clam
 Nuculida - Praenuculidae
Palaeoconcha sp., ? Praenucula sp.
Palaeoconcha sp. Miller 1889 clam
? Praenucula sp. Pfab 1934 clam
originally entered as "? Praenucula sp."
 Nuculanida - Cucullellidae
Nuculites sp.
Nuculites sp. Conrad 1841 clam
 Nuculanida - Malletiidae
Palaeoneilo sp.
Palaeoneilo sp. Hall and Whitfield 1869 clam