Cockroaches represent a primitive and highly successful group of animals whose origins extend back at least 300 million years. Fossil evidence suggests little change in their general body form since that time.
While there are about 3,500 species of cockroach worldwide, only about ten species have seriously exploited human dwellings.
Cockroaches eat virtually everything; animal or human food or beverage plus any dead animal or vegetable material. These may include cardboard, hair, glue, leather, fabrics, starchy book binding and wallpaper glue to name a few. Typically, cockroach infestations develop in and around buildings and other structures that provide food, shelter and offer the preferred conditions of temperature and humidity. A commercial kitchen, and some severely infested domestic homes, may support thousands of cockroaches in various developmental stages.
Cockroaches often dwell in environments that support the growth of organisms causing diseases harmful to humans e.g. sewers, grease traps and other sources of polluted water and refuse, by contaminating food products, utensils and surface areas with their droppings, cast skins, empty egg cases and vomit.
Light amber-brown with two dark longitudinal stripes on the pronotum. 12 to 15mm long.
Commonly infests the interior of buildings, mostly in and around kitchens - domestic and commercial pantries, storerooms and other food handling areas. They are commonly found in and behind stoves, sinks, refrigerators, almost any electrical appliances. They also take harbourage in any crack or crevice at all as long as it is close to water, food and warmth. This species does not fly but is a prolific breeder.
Reddish brown, pale yellow border around pronotum. Wings completely cover the abdomen. 35 to 40mm long.
Often found in subfloors, sewers, grease traps, wall voids, cellars, roof voids, in and around refuse tips. May be a concern around hospitals, bakeries, food stores, warehouses and other foods handling establishments. Flies in warm weather and often travels for food.
Pale brown with very pale bands across the thorax and abdomen. Female has reduced wings and male is fully winged. 10 to 14mm long.
Commonly infests houses, offices and other buildings. Not restricted to kitchen areas - prefers drier areas e.g. bookcases, desks, wardrobes, around picture frames, in stored files, light fittings. Infestations are often found throughout the building. Flies when warm or disturbed.