Cockroaches are insects of the order Blattodea, sometimes called Blattaria, of which about 30 species out of 4,600 total are associated with human habitats. About four species are well known as pests.
Among the best-known pest species are the American cockroach, Periplaneta americana, which is about 30 mm (1.2 in) long; the German cockroach, Blattella germanica, about 15 mm (0.59 in) long; the Asian cockroach, Blattella asahinai, also about 15 mm (0.59 in) in length; and the Oriental cockroach, Blatta orientalis, about 25 mm (0.98 in). Tropical cockroaches are often much bigger, and, contrary to popular opinion, extinct cockroach relatives and ‘roachoids’ such as the Carboniferous Archimylacris and the Permian Apthoroblattina were not as large as the biggest modern species.
TYPES OF COCKROACHES:
The American cockroach is the largest of the house-infesting cockroaches. Despite its name, the American cockroach is not native to North America, but was probably introduced via ships from Africa in the 1600s.
Brown-banded cockroaches get their name from the two lighter bands they have across their dark brownish bodies. Male brown-banded roaches have full wings that reach beyond the tip of their pointed abdomens, but females have underdeveloped wings that prohibit them from flying. The brown-banded cockroach can live for about 206 days.
The German cockroach is the most common species of the cockroach. German cockroaches can breed at a rate of up to six generations per year. The German cockroach can fit through an opening as small as 3/8 inch in width.
Oriental cockroaches are believed to be of North African origin, despite their name. Oriental roaches are sometimes called “waterbugs” because they come out of drains, and “black beetle cockroaches” because of their smooth, dark bodies. They are known for their strong, unpleasant, “roachy” odor.