Biogeographic variation in Thecamoebian (Testate amoeba) assemblages in lakes within various vegetation zones of Alberta, Canada

Lisa A. Neville^1*, David G. Christie¹, Francine M. G. McCarthy¹ and Michael D. MacKinnon²

¹Department of Earth Studies, Brock University, St. Catharines, ON L2S 3A1, Canada.

²Department of Earth Sciences, Carleton University, Ottawa, ON K1S 5B.

³OSPM Solutions Ltd., 470 Beach Blvd. Hamilton, ON L8H 6X2, Canada.

*Corresponding author. E-mail: Ineville@connect.carleton.ca.

Accepted 7 May, 2010

     Abstract

Thecamoebians (Testate amoebae) have proven to be valuable proxies commonly used in environmental and paleoenvironmental studies. A better understanding of their geographic distribution and environmental parameters influencing this distribution is required for further thecamoebian research. Thecamoebians were analyzed from twelve lakes spanning five drainage basins and four vegetation zones, representing a variety of environmental and limnological parameters in Alberta, Canada. Species diversity is low throughout the study sites, ranging from 1.35 to 2.17, with various strains of Difflugia oblonga, Centropyxis constricta and Centropyxis aculeata dominating the fauna. Climate, as reflected in the vegetation zones, appears to be an influencing factor on species and strain distributions. Low-diversity assemblages strongly dominated by C. aculeata and C. constricta, characterize lakes in the rocky mountain region. Slightly, more diverse assemblages dominated by D. oblonga and Cucurbitella tricuspis characterize lakes in the grassland region. The highest Thecamoebian diversity was found in both the Boreal Forest and Parkland zones. The Boreal Forest is dominated by D. oblonga together with C. constricta, C. tricuspis and C. aculeata, while the Boreal Parkland is dominated by D. oblonga along with C. constricta and C. aculeata.

Key words: Thecamoebians, Testate amoebae, Biogeographic, Alberta