SCIENCE: ENSIGN WASP

This strange-looking bug resembles a cross between a house fly and a cricket. You may have seen it and wondered what it is. One answer is "your friend against cockroaches." Another answer is "ensign wasp." The adult wasp feeds on pollen from certain flowers and its larvae feed on roach eggs. The adult female lays several eggs within a roach egg casing. When the eggs hatch the wasp larvae eat the roach eggs. The wasps don't sting. [Source: http://www.whatsthatbug.com/2009/07/04/ensign-wasp-4/, http://edis.ifas.ufl.edu/BI036, et al.]