The German cockroach is the most common cockroach species found by pest management professionals worldwide.
They can be found in a variety of human-occupied spaces such as apartments, restaurants, food processing facilities, and nursing homes just to name a few of the more common areas. German cockroaches are easily transported because they can be found in grocery bags, cardboard boxes, drink cartons, and secondhand appliances such as refrigerators, televisions, and microwaves.
German cockroaches are believed to be capable of transmitting disease-causing organisms such as the hepatitis virus and have been implicated in the spread of typhoid and dysentery. Indoor infestations of this cockroach can be a source of allergens and pose a risk for asthma among some populations. The infestations levels of cockroaches and allergens are found to be directly related to cockroach density, housing disrepair, and sanitary conditions.
They can usually be found in residential and commercial kitchens and bathrooms however an infestation can occur in any area where people eat and drink. In homes, this may be dining rooms, living rooms, and bedrooms. Any crack or crevice located near a source of food and/or water can harbor cockroaches and they can fit through an opening as small as 3/8 inch in width. For every cockroach in view during the day, there could be hundreds hidden inside wall and ceiling voids, behind cabinets, and inside appliances. A favorite location of this cockroach is inside an arrow crevice with its antennae extended out. Typical locations where this cockroach may be found are in the cracks between cabinets and walls, the flange under the kitchen sink, and the space between door corners and jambs.
The German cockroach prefers a temperature of around 85 - 95 degrees with humidity at 90 to 95%. It has an incomplete metamorphosis which is just the egg, nymph, and adult, and the entire life cycle is completed in about 100 days.
The nymphs of the German cockroach are dark brown to black in color, with distinct dark parallel bands running the length of the pronotum and they don’t possess wings. The adults are around 3/8 - 5/8 inch and are brown to dark brown in color with two distinct parallel bands. The male body is thinner and slender, and the abdomen is tapered whereas the female has a stout body, and the abdomen is rounded.