Synthesis of a Middle Pennsylvanian soft-bodied fauna from western Illinois

Collection and examination of thousands of concretions from the Francis Creek Shale (Middle Pennsylvanian) of Fulton County, in western Illinois, has revealed a diverse euryhaline (Essex) assemblage of the Mazon Creek biota. Previous studies suggested the Essex fauna of western Illinois is of low diversity; however forty-one species are described here, including two new species of cnidarians (Solmacula fodina and Circularia gelataforma). The fauna is represented by cnidarians, polychaete worms, non-annelid worms, arthropods, a holothurian, numerous chordates (mainly fishes), and problematic fossils. Many species had been previously known only from the Mazon Creek area of northern Illinois. In an examination of 67 localities containing fossiliferous concretions from Illinois and Missouri, abundances and ranking were culled to determine the dominant animals for the Essex fauna. For western Illinois, represented in the analyses by a single strip mine and a newly discovered outcrop, the top ten dominant organisms or groups are Essexella asherae Foster, Belotelson magister (Packard), coprolites, Tullimonstrum gregarium Richardson, Esconichthys apopyris Bardack, indeterminate animals, trails, Etacystis communis Nitecki and Schram, Strobeus cf S. primigenius Conrad, and fish parts. The Fulton County concretions lack most of the benthic organisms found in the Mazon Creek area.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Geology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Sroka, Steven Daniel

Contributors dc:contributor

• Blake, Daniel B.

• Paleontology
• Paleoecology
• Paleozoology

Statement dc:rights

• Copyright 1996 Sroka, Steven Daniel

Language dc:language

eng

Identifier

AAI9625199
(UMI)AAI9625199

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/21299