(A & B) Two adult zebra mussels Dreissena polymorpha attached to the dorsal carapace of an odonata nymph Epicordulia sp. (Corduliidae) larva. The nymph was collected on Lake Mendota, Madison, WI (43°04′38.8′′N 89°24′10.6′′W) on 24th October 2016 via a minnow trap in 2 m of water (Photo credits, A.L. Stevens). The criteria used to identify species are described by Bouchard et al. (2004). (C) Adult crayfish specimen extensively fouled by D. polymorpha (Photo credit, Minnesota Department of Natural Resources).