German cockroaches are a small species of cockroach, typically about 1.1 to 1.6 cm (0.43 to 0.63 in) long. They vary In color from tan to almost black, andthey have two dark, roughly parallel, streaks running from behind the head to the base of the wings. Although Blattella germanica has wings, it can barely fly at all, though it may glide when disturbed. Of the few species of cockroach that are domestic pests, it probably is the most widely troublesome example.
• Though nocturnal, the German cockroach occasionally appears by day, especially if the population is crowded or has been disturbed.
• However, sightings are most frequent in the evening, when someone suddenly brings a light into a room deserted after dark, such as a kitchen where they have been scavenging.
• When excited or frightened, the species emits an unpleasant odor.