Tyler S, Schilling S, Hooge M, and Bush LF (comp.) (2006-2016) Turbellarian taxonomic database. Version 1.7 http://turbellaria.umaine.edu (data licensed under Creative Commons Attribution-NonCommercial-ShareAlike 2.0; material adapted: formatted and edited)
Van Steenkiste, Niels, Stefan Gobert, Paul Davison, Jurek Kolasa, Jurek Kolasa, and Tom Artois
Freshwater Dalyelliidae from the Nearctic (Platyhelminthes, Rhabdocoela): new taxa and records from Ontario, Canada and Michigan and Alabama, USA
Journal/Book Name, Vol. No.:
Zootaxa, issue 3091
Available online at http://mapress.com/zootaxa/content.html
Van Steenkiste et al. (2011) treat Prostoma marginatum Leidy, 1847 as a (uncertain) synonym of Castrella pinguis (Silliman, 1884) but do not provide an unacceptability reason
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