•  
  •  
 

Document Type

Research

Keywords

Late Mississippian; Chesterian; Talarocrinus Zone; Pella Formation; Mahaska County, Iowa; Echinodermata; Echinoidea; Echinocystitidae; Praepholidocidaris pellaensis; Pholidocidaris; paleoecology

Abstract

Praepholidocidaris pellaensis, n. gen., n. sp., is described from basal Chesterian rocks in the vicinity of Oskaloosa and Givin, Mahaska County, Iowa. The new genus is characterized by its small number of ambulacral and interambulacral plate columns, adorally expanded ambulacra, unequal ambulacrals with perforate primary spines, and interambulacrals with primary spines only on adradial plate columns. Age relationships of the Pella Formation and the paleoecology of its echinoderm fauna are reviewed. It is concluded that the echinoderms represent an opportunistic assemblage and the bulk of the echinoderm fauna supports assignment of unit C of the formation to the Talarocrinus Zone (of Horowitz and Strimple, 1974), basal Chesterian.

Publication Date

September 1977

Journal Title

Proceedings of the Iowa Academy of Science

Volume

84

Issue

3

First Page

98

Last Page

105

Copyright

© Copyright 1977 by the Iowa Academy of Science, Inc.

Language

EN

File Format

application/pdf

Share

COinS
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.