Cricket with flat head: male body length 15 ~20mm, female body length16 ~ 2 mm; The male wing is 9 ~ 1 1 mm, and the female wing is 9 ~ 12 mm. The body is dark brown. The head of the male worm obviously protrudes forward, the front edge is curved in black, and there are 1 orange or reddish-brown horizontal bands behind the edge. The face is dark maroon to brown-black, with 1 transverse spot in the center and the middle eye hidden in it. The width of the front chest backboard is greater than the length; The lateral plate is long at the front and short at the back, inclining downward, with 1 macula in front of the lower edge. The front wing reaches the ventral end; The hind wings are slender and the ventral end looks like a tail, but they often fall off leaving only traces. The feet are tan and black. The acoustic mirror is nearly square with 2~3 oblique veins.
Beijing rape gourd: long and narrow, female body length is 20.6~24.3mm, male body length is 18.0 ~ 22.4mm, the back is dark brown and shiny, and the ventral surface is yellowish brown. There are two crescent-shaped lines on the front chest back plate, and the rear edge of the middle chest and abdomen plate is concave. The front wing is light brown and shiny, and the rear wing tip is longitudinally folded to expose the ventral end, which is very long and looks like a tail beard. The hind leg joint is strong, and there are 6 thorns in the tibial joint, with a distance of 6.
Adults like to live in the shade, especially under wet and thin grass, lurk during the day and feed at night, with the peak activity at 19: 00 ~ 22: 00. Adults are vocal, aggressive, sometimes killing each other, and weak phototaxis. The eggs of Eichhornia crassipes in Beijing are laid in the sunny soil layer of 2cm, with 75.4 eggs laid by a single female, the nymphae stage is about 63 days, and the adult life span is 145.3 days. Crickets lay eggs in 1.2cm soil layer, with 5~ 13 eggs per head. The average duration of nymph is 62 days. Because of the different nutritional conditions and food, the duration of nymph is slightly different. The first instar larvae eat the epidermis of mesophyll, and after the second and third instars, they eat mostly from the leaf edge, lacking carving.
The peak of cricket wine is from mid-August to early September, and the peak is from August 23 to 29, with an increasing trend year by year. There is more precipitation from the end of April to May, and the occurrence of crickets is large. According to the comprehensive analysis of insect population and precipitation from 200/KLOC-0 to May 2006, there is a positive correlation between its occurrence and precipitation (as shown in the above table). The occurrence density of crickets in different crop fields is different. Vegetable field is more important than grain field, soybean, peanut and corn field are more important than cotton and sweet potato field, and the population density of low-lying land with relatively shallow water level is high.