DNA barcoding and morphometric data for Truncilla donaciformis and Truncilla truncata (Bivalvia: Unionidae)

Closely-related unionid species often overlap in shell shape and can be difficult to accurately identify in the field. Ambiguity in identification can have serious impacts on conservation efforts and population surveys of endangered species. Truncilla donaciformis and T. truncata are sister species that overlap in their distributions and frequently co-occur in central North America. Because T. donaciformis is endangered in Canada and imperiled in some U.S. jurisdictions, co-occurrence with the morphologically-similar T. truncata means that misidentification could have serious impacts on status assessments and recovery efforts. The objectives of this study were: (1) to employ morphometric analyses in combination with DNA barcoding to quantify morphological differences between T. donaciformis and T. truncata and (2) to use these methods to confirm field identifications and identify problematic specimens. Truncilla specimens were photographed and visceral mass swabs taken from four rivers ...