ABSTRACT
The pygmy backswimmers are distinguished by their strongly convex form, small size, coleopteriform hemelytra, and hind legs set with long hairs for swimming. All species are truly aquatic, frequenting weedy ponds and other slow-water habitats where they prey on ostracods, Daphnia, and mosquito larvae. Populations reach their highest densities in small ponds and shallow portions of larger lakes, where they gain protection from predation by fish. Pleidae are badly in need of revision in North America, and key to people species exists. Species concepts are in certain cases confused due to differences in color pattern and hemelytral sculpturing correlated with varying degrees of wing development.
