US Geological Survey


Date of this Version



Published in The Prairie Naturalist 34(1/2): March/June 2002. Published by the Great Plains Natural Science Society


On 14 June 1994 we collected a living specimen of Valvata lewisii morph ontariensis at the Cottonwood Lake Study Area, Stutsman County, North Dakota. The voucher specimen is housed in the aquatic invertebrate collection at Northern Prairie Wildlife Research Center. We captured the specimen in a funnel trap (Swanson 1978) in the shallow marsh zone of a seasonal wetland. This is in contrast to the typical habitats for this species, which are large lakes and rivers (Clarke 1981). Water depth at the site where we collected Valvata lewisii ontariensis was 33 cm. Shallow marsh plants in the wetland included water smartweed (Polygonum amphibium), turion duckweed (Lemna turionifera), slough sedge (Carex atherodes), star duckweed (Lemna trisulca), and whitetop (Scolochloa festucacea).