North end of Orchard Creek Exposure, 1.6 km north of Thebes (Ordovician of the United States)

Where: Alexander County, Illinois (37.2° N, 89.5° W: paleocoordinates 24.8° S, 62.9° W)

• coordinate based on political unit

• basin-level geographic resolution

When: Paraorthograptus pacificus conodont zone, Orchard Creek Shale Formation, Richmondian (449.6 - 445.5 Ma)

• "U. Ord. (Ashg-m; Maquoketa) b/w Thebes SS below and Girardeau Ls above" - equated with Richmondian on instruction of M. Patzkowsky 20 Aug 1999

•

•Top of Paraorthograptus pacificus zone & Ordochitina nevadensis zone.

• group of beds-level stratigraphic resolution

Environment/lithology: shallow subtidal; burrowed, green, silty limestone and shale

• "green-gray silty shale and thin bedded limestone; irregular wavy bedding, burrowing"

Size class: macrofossils

Primary reference: T. E. Guensburg. 1988. Systematics, functional morphology and life modes of Late Ordovician edrioasteroids, Orchard Creek Shale, southern Illinois. Journal of Paleontology 62:110-126 [M. Uhen/J. Ju]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 382: authorized by Jack Sepkoski, entered by Mike Sommers on 20.11.1998

Creative Commons license: CC BY (attribution)

Taxonomic list

• "T.E. Guensburg, 1988. Systematics, functional morphology and life modes of Late Ord. edrioasteroids, Orchard Cr. Shale, southern IL. J. Paleo 62:110-126"
Show authors, comments, and common names
unclassified
  -
? Pteroida indet.
? Pteroida indet.
? Byssate bivalve - originally entered as "? Pteroida indet."
Crinoidea
  -
Crinoidea indet.
Crinoidea indet. Miller 1821 Sea lily
other crinoids
 Dendrocrinida - Dendrocrinidae
Dendrocrinidae indet.
Dendrocrinidae indet. Wachsmuth and Springer 1886 Sea lily
dendrocrinid crinoid
 Rhombifera - Callocystitidae
Lepadocystis sp.
Lepadocystis sp. Carpenter 1891
Edrioasteroidea
 Isorophida - Lebetodiscidae
Euhydrodiskos diktyotos n. gen. n. sp.
Euhydrodiskos diktyotos n. gen. n. sp. Guensburg 1988
originally entered as "Euhyrodiskos sp."
 Isorophida - Agelacrinitidae
Savagella illinoisensis, Hystrichopsydrax sandersi n. gen. n. sp.
Savagella illinoisensis Miller and Gurley 1895
Hystrichopsydrax sandersi n. gen. n. sp. Guensburg 1988
 Isorophina - Isorophidae
? Isorophus sp.
? Isorophus sp. Foerste 1916
originally entered as "? Isorophus sp."
  - Pyrgocystidae
? Pyrgocystis sp.
? Pyrgocystis sp. Bather 1915
originally entered as "? Pyrgocystis sp."
Stylophora
 Mitrata -
Diamphidiocystis sp.
Gastropoda
 Streptoneura -
Archaeogastropoda indet.
Archaeogastropoda indet. Thiele 1925 snail
archaeogastropods
 Lophophorata -
Tentaculitida indet.
Tentaculitida indet. Ljaschenko 1955
tentaculitids
Strophomenata
 Strophomenida - Rafinesquinidae
Rafinesquina sp.
Rafinesquina sp. Hall and Clarke 1892
originally entered as "Raphinesquina sp."
Rhynchonellata
 Orthida - Dalmanellidae
Resserella sp.
Resserella sp. Bancroft 1928
Bryozoa
  -
Bryozoa indet.
Bryozoa indet. Ehrenberg 1831
bryozoans, several gn
Trilobita
 Corynexochida - Illaenidae
Bumastus sp.
Bumastus sp. Murchison 1839 trilobite