Dissertations and Theses @ UNI


Open Access Thesis


Decapoda (Crustacea)--Iowa;


Between 1 March 1977 and 30 September 1978, a survey was made of the species of decapod crustaceans present in Iowa. During this time period all of Iowa's 99 counties were surveyed. A total of 2390 specimens representing 500 lots were collected from 492 different sites in Iowa. Specimens were collected by seining, dip netting, hand collecting, excavation, and trapping. An additional 1944 specimens were examined from existing collections. Seven species of Cambaridae (Cambarus diogenes diogenes Girard, Orconectes immunis (Hagen), Orconectes iowaensis Fitzpatrick, Orconectes rusticus (Girard), Orconectes virilis (Hagen), Procambarus acutus acutus (Girard), and Procambarus gracilis (Hagen)) and one species of Palaemonidae (Palaemonetes kadiakensis Rathbun) were identified. C. d. diogenes and O. virilis were found to occur statewide while O. immunis, O. iowaensis, O. rusticus, P. a. acutus, P. gracilis, and Palaemonetes kadiakensis were found to have limited distribution. Data on life history, habitat, and ecology are included. Taxonomic problems with O. iowaensis, O. rustious, and O. yirilis were noted and discussed. Descriptions of variants of O. rusticus and O. virilis are included. A regional classification scheme based on the primary aquatic environment of each region was developed. Using the regions described in this scheme, similarity indexes were calculated. Similarity indexes were also calculated for Iowa and adjacent states. On the basis of these indexes, a decrease in species diversity was noted from south to north and from east to west. Consideration was also given to the environmental factors affecting decapod populations with climate, pollution, and habitat modification being discussed.

Year of Submission


Degree Name

Master of Arts


Department of Biology

First Advisor

Virgil E. Dowell, Chairman, Thesis Committee


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Date Original


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