Aliases: German cockroach, German cockroach
Taxonomic status: Cockroaches Blattaria, Blattellidae
Morphological characteristics: small body, light russet brown. The male is long and narrow, with a body length of 10 to 13 mm, and the female is broad and short, with a body length of 11 to 14 mm. The dorsal plate of the anterior thorax has 2 longitudinal black stripes that are straight on the inside. The forewings of males are 9.5 to 11 mm long and the females are 11 to 13 mm long. The male has a narrow abdomen, specialized dorsal plate of the 7th segment, translucent supra plate, and the lower genital plate is asymmetrical to the left and right, ill-shaped, with a groove in the left posterior margin, and 1 lateral fragment on each side of the base, that is, a lateral segment of the 9th dorsal plate, extending backwards The lateral part of the lateral plate is wider, the end is blunt and rounded, and the posterior end of the left fragment is far from the lateral edge of the groove. The female has a broad and short abdomen, a broad base, russet brown, a narrow end, white, obtuse ends, a lateral margin oblique, slightly concave, and a slightly triangular overall; the lower genital plate is broad, the surface is raised, the anterior margin is nearly semicircular, the posterior margin is rounded, and the tail whiskers are strong and hairy. The initial spawning sheath is milky white and gradually changes to a yellowish brown color. Nymphs are 5 to 7 years old, with young nymphs dark brown and dorsal longitudinal markings gradually appearing from young to advanced age.
Biological characteristics: German cockroaches can breed 5 to 6 generations in 1 year, and their fertility is extremely strong. Temperature and food affect the distribution of German cockroaches, at 40 ~ 50 ° C or -5 ~ 5 ° C, the survival time of German cockroaches with the increase or decrease of temperature shows a downward trend, German cockroaches have higher humidity requirements, nest distance from water sources and food generally no more than 4m. When water and food are cut off, German cockroaches survive only 2 weeks.
Geographical distribution: native to South Asia, some scholars believe that it originated in Africa. It spreads over long distances with inter-regional economic trade.
Distribution in China: Distributed all over the world, it is distributed in the tropics, subtropics, temperate and cold zones. Now it is mainly distributed in Beijing, Liaoning, Heilongjiang, Shanghai, Fujian, Guangdong, Guangxi, Sichuan, Guizhou, Yunnan, Tibet, Shaanxi, Xinjiang and other places.
Invasion hazards: German cockroach secretions can spoil food, causing human poisoning. It will bite and destroy food, paper, cultural relics, electronic equipment, etc., while carrying dysentery bacillus, tuberculosis bacillus, poliovirus, hepatitis B virus and other pathogenic bacteria and threaten human health, seriously affecting the human living environment and quality of life.
Prevention and control methods: keep indoor places clean and hygienic. A mixture of eugenol, α-terpinol, and cinnamyl alcohol can be used to prevent German cockroaches. Chemical control of German cockroaches is more convenient and effective, such as spraying filfluramid, chlorpyrifos, permethrin agents, can also be put into the bait, spraying and release should pay attention to environmental pollution and human and animal health.
