Natural hosts.—Cockroaches, Italy (Beaumont, 1954).
Tachysphex fanuiensis Cheesman
Natural hosts.—Graptoblatta notulata, Society Islands (Cheesman, 1927, 1928).
Cockroach ("except for its smaller size [it] much resembles Graptoblatta notulata."), New Caledonia (Williams, 1945).
Nesting sites.—Patches of dry soil (Cheesman, 1928); coarse sand at base of a bank (Williams, 1945). Behavior.—The female wasp pounces on the cockroach and stings it into immobility; she carries her prey in flight to the nest. Two to 13 cockroaches may be found in one nest; and one or more wasp eggs may be deposited in one nest. The egg is attached at one end to the host's thorax behind a forecoxa. Nest is sealed with dry pellets of soil. The cockroaches apparently do not recover from the wasp's sting.
Tachysphex lativalvis (Thomson)
Natural hosts.—Ectobius lapponicus, adults, Sweden (Adlerz, 1906); France (Maneval, 1932).
Ectobius pallidus, nymphs, France (Ferton, 1894, 1901; Maneval, 1932; Deleurance, 1946); Italy (Grandi, 1928).
Ectobius panzeri, Netherlands (Bouwman, 1914).
Ectobius sp., Denmark (Nielsen, 1933).