Saddle crab spider (saddle crab spider)

One of the predatory tussah pests, mainly harming 1-2 instar tussah silkworms. Belongs to the family Araneae, Araneae, scientific name XysticusephippiafusSimon. There are many species and wide distribution of spiders that damage tussah silkworms, which occur in all tussah areas all over the country. Twenty-six species of silkworm-damaging spiders have been found in Liaoning area. in addition to saddle-shaped flower crab spiders, there are three-protruding flower spiders, tarsal Xiaoyao spiders, long shoulder spiders and so on.

In the adult spider, the female spider is 7-8mm long, brown or yellowish brown, with dark brown longitudinal stripes on both sides of the head and chest, and a light brown line in the center. There are several black thorns on the front edge of the head and chest. The first and second pairs of feet are longer than the last two pairs, and thick, dark color, with dark brown spots. The length of the male spider is 4-5mm, the head, chest and abdomen are dark brown, the legs and knees of the first and second pairs of foot are dark brown, and the other segments are light yellow, which is obviously different from that of the female spider. The egg is oval, the length of the egg is 0.9-1.0mm and the length of the 1-year-old spider is 1.1-1.2mm, the body is light yellow, the foot is white, and the eyes are reddish brown. The body length of the 6-7-year-old nymph is 3.9-6.8mm, the body is dark brown or dark brown, and the other colors and shapes are basically the same as the adults.

Habits are from generation to generation in Liaoning area. Adult spiders, sub-adult spiders and nymph spiders overwinter in caves at the root of oak trees. The overwintering adult spider begins to mate and lay eggs in the middle of May of the following year. The female spiders lay eggs 17-21 days after mating, and the spawning period is from mid-June to mid-July. The life span is 25-114 days. The life span of female adult spiders is more than 9 months. The period of adult spider activity is from April to October, and the peak period is from mid-June to early October.

The saddle-shaped flower crab spider can harm 1-2-year-old silkworms from May to October. A saddle-shaped flower crab spider can eat up to 4 first-instar tussah silkworms per day, with an average of 1.7. During the peak period, an average of 65 spiders were found per 100M2.

10-15 days before the silkworm enters the silkworm farm, the silkworm farm can be sprayed with 200-300 times aqueous solution of 10% deworming concentrate emulsion. 1.5% phoxim powder can be sprayed on the ground of the silkworm farm, and silkworms can be released on the oak tree 7 days after spraying. Natural enemies are ants, wasps, nematodes, mites, Beauveria bassiana.