I. Basic concepts
Cockroaches generally refer to insects belonging to "cockroaches" (scientific names), of which only dozens will invade human homes, and several will be kept by humans as pets and used as food for pets. Most species can only be seen in wild mountains, streams and forests or insect museums.
The body is flat, dark brown and usually of medium size. Small head, move. Antennas are long and filiform, and compound eyes are developed. The wings are flat, the front wing is cortical, the rear wing is membranous, and the size of the front and rear wings is basically the same, covering the rear of the abdomen; Some species have no wings. Not good at flying, can run. Not completely perverted. Lay eggs in the egg sheath. There are about 6000 species, mainly distributed in tropical and subtropical regions. Live in the wild or indoors.
Two. common name
(Hong Kong, Guangdong), Mrs. Huang, Sao Jia (Guilin dialect), You Huo (Xupu dialect), You Scar, Elegance (Cantonese, pronounced yuēyóu in Putonghua and gad6 zad6 in Cantonese), Huancha (Meizhou dialect), Gagua (second voice) Sap (Guangxi Zhuang dialect), and Holland Pavilion.
Three. morphological character
According to the ecological habits of cockroaches, a biologist once came to a conclusion: if there is a global nuclear war on the earth one day, all creatures in the affected area, including humans and even fish, will disappear, and only cockroaches will continue their lives! This is because under normal circumstances, the radiation that the human body can bear is 5 rem, and once the total radiation exceeds 800 rem, it will die. Blattella germanica can tolerate 9000~ 105000rems, and Periplaneta americana can tolerate 967500rems! Rems should be rem, which means radiation dose.
Most of them look the same, but if you look closely, you can still see the difference. At present, taxonomists divide cockroaches into about 6,000 species, of which about 50 species are pests, such as common Asian cockroaches. In addition, Periplaneta americana, Blattella germanica, brown cockroach and Australian cockroach are also widely distributed. There are about 200 species in China, and the common indoor cockroaches are about 10, which varies from place to place. Blattella germanica and Periplaneta americana are common.