Roachlike Stoneflies

The Peltoperlidae, also known as roach-like stoneflies or roachflies, are a family of stoneflies.

The family Peltoperlidae comprises 11 genera and 46 known species. Species are semivoltine, meaning their lifecycles last one to two years. Adults of the family usually emerge in late spring or early summer, April through June. Larvae are flattened and brown in color, and they are roach-like in appearance because of the expanded thoracic plates covering the bases of their legs, heads, and abdomens. Tapering gills occur on the thorax at the bases of the legs. These tracheal gills are multifunctional and key to many biological processes. No dense tufts or branching gills are found on their thoraces or abdomens, unlike other Plecoptera families. The larvae also possess broad, chisel-like mandibles. Adults have two ocelli in addition to their two compound eyes. Male epiprocts are sclerotized and rod-like in shape, and both sexes lack cross-veins in the anal lobe of the forewings.