The American Cockroach, Periplaneta americana¹

D. R. Suiter and P. G. Koehler²

APPEARANCE

The American cockroach is the largest of the house-infesting cockroaches, being 1½ inches long with fully developed reddish/brown wings, and light markings on the thorax (Figure 1). The sexes are almost identical in size and appearance. The female has a broader abdomen than the male. However, only the male has both cerci and stylets. The wings of the male extend from 4 to 8 mm over the end of the abdomen, while in the female they are equal to or only slightly longer than the abdomen.

American cockroach.

Figure 1.

HABITAT

This cockroach is a common inhabitant of sewage systems. Observations after heavy rain show that basements in numerous cities throughout the United States have heavy infestations of American cockroaches. The American cockroach is found most commonly in restaurants, grocery stores, bakeries, and where food is prepared or stored. During the summer months, alley ways and yards may be badly infested.

BIOLOGY AND HABITS

Egg capsules are often glued to surfaces and are often covered with paint or other building material, blending well with the surroundings. American cockroaches do not drop the egg cases indiscriminately, but usually hide them with great care in crevices, or bury them in soft wood or workable material. This clearly has survival value since predators and parasites attack poorly protected egg capsules or pest control technicians may squash egg capsules easily spotted around exterior door frames. The incubation period is 38-49 days, and the number of egg cases produced by the female is from 6 to 14, with an average of 9.5. A female may produce 30-90 egg capsules at intervals of approximately 4-7 days.

The egg capsule may contain up to 16 eggs; however, the average number of young to emerge is 13.6. The whitish, newly-emerged nymphs begin to run around actively in about 10 minutes. The first few molts of the nymph occur at approximately monthly intervals, but thereafter may vary from 1 to 6 months. The American cockroach molts 13 times before reaching maturity. The duration of the nymphal period from records now available varies from 285 to 616 days, with an average of 409, although the final average will be over 450 days. The American cockroach may reach sexual maturity in seven months under optimum conditions. Adult females live 102-588 days, with an average of 440 days.

American cockroaches have been found flying around street lights in Texas. They are reported capable of long flights, but their flight in the North is more of a gliding type.

CONTROL

Because the American cockroach is found indoors and outdoors in very wet situations, applications of insecticides to basement walls, wood scaps, and other infested locations are recommended. Residual barrier sprays substantially reduce American cockroach populations around houses. Power dusting of sewage lines, crawl spaces, false ceilings, wall voids, and trash chutes is an effective method of control. Space sprays, ULV treatment, or contact aerosols and sprays can be used in basements and utility rooms. Loose baits and other formulations better suited for damp locations can provide effective control in basements and similar areas.

Footnotes

This document is ENY232, one of a series of the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date October 1991. Reviewed May 2003. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.

D.R. Suiter, research assistant; Philip G. Koehler, professor, Entomology and Nematology Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville FL 32611.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.

U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Millie Ferrer-Chancy, Interim Dean.