Corixia / back swimmer
Given the similarity of form and function both of these aquatic bugs can be represented by the following fly. This fly is best fished on a floating line that has been greased to within a meter of the fly or under a dry fly. It generally works well just sinking in the water column or moving naturally with the water current. If unnoticed try a couple of short figure of eight strips punctuated by a long pause to represent the natural swimming action of both bugs or a gentle lift to mimic “the natural” rising to the surface to breath.