Cerceris fumipennis

Cerceris fumipennis, the only species of buprestid-hunting Crabronidae occurring in eastern North America, is found throughout the continental United States east of the Rockies: from Texas and Florida, north to Maine and Wyoming and is now known from more than twenty colonies of varying size in Canada. The wasps are most often nesting in open areas of hard-packed sandy soil surrounded by woody habitat suitable for their buprestid beetle prey. Ontario colonies are associated with somewhat disturbed sites compacted by human activity such as baseball diamonds, parking areas, infrequently used roads, roadsides, footpaths and the soil around campfire pits. Cerceris fumipennis is distinguished by five conspicuous characteristics: Cerceris fumipennis is a solitary ground-nesting wasp. Each lone female constructs and attempts to maintain a single subterranean nest for the duration of the flight season. Her solitary nest is in close proximity to others, forming a neighborhood or informal colony of nests. The nest’s entrance is easily visible, marked by a small circular mound of earth. Each nest is composed of a single entrance hole which leads to subterranean cells. Like many crabronidae and sphecid wasps, C. fumipennis females mass provision for their cells before laying an egg in them. Adult females provision their cells with beetles of the family buprestidae. When hunting for buprestid prey, the maximum foraging range of the wasp is estimated at 2 km with an estimated average flight distance of 750 meters from the nest. Once prey has been found, a female wasp will typically attack a target beetle by alighting on it, climbing over it, and grabbing it by the thorax with her mandibles before inserting her stinger into the base of the beetle’s leg (in the membrane of the coxal joint, a gap in the buprestid’s armour) and injecting a paralytic venom. Once at the nest entrance or in the burrow, the female wasp will sometimes re-sting poorly paralyzed prey in the same joint.