original descriptionHenderson J. (1929). Non-marine Mollusca of Oregon and Washington. <em>The University of Colorado Studies.</em> 17(2): 47-190. page(s): 53 [details]
additional sourceInvertEBase. (2015). Authority files of U.S. and Canadian land and freshwater mollusks developed for the InvertEBase project (invertebase.org). [details]