间斑寇蛛生活习性之初步观察

间斑寇蛛(Latrotectus tredecimguttatus)雌蛛平均体长10.92 mm,头胸长4.18 mm,腹长8.19 mm,头胸部褐色、紫褐色或黑色,呈梨状或坛状,腹部卵圆形或倒桃形,黑褐色;雄蛛平均体长4.52 mm,头胸长2.08 mm,腹长2.82 mm,头胸部色同雌蛛,腹部卵圆形,褐色或黑色,背面前缘有一后凹弧形斑,往后有3列各4块黄色斑.生活于荒坡、农田,在石缝、土洞、低矮植物丛近地面处织不规则网捕食各类昆虫,以直翅目、鞘翅目昆虫居多.5～6月交配,雌雄蛛以腹对腹姿势、头尾方向一致地悬吊在网上,雄蛛以左、右触肢轮流交配,全过程约1.5 h,配毕雄蛛迅即离开,雌蛛并不追赶,未发现雌蛛追杀雄蛛.母蛛于5～8月产卵,7～8月为产卵高峰期.卵袋呈圆球形,略似桃状,淡褐色至棕色,袋壁较厚,内层为白色绒状丝,平均体积13.2 mm×12.0 mm×11.6 mm,每袋内含卵201.1粒,1只母蛛平均织卵袋2.68个,总产卵数539粒.5～7月所产卵经发育成小蛛直至走出卵袋,约需30 d;7月下旬至8月所产卵,当年发育成小蛛,不离开卵袋,至次年3、4月间走出卵袋.室内饲养的成年雌蛛多在9～10月间死亡,未见成年雌蛛越冬;当年7～8月从卵袋中孵出的小蛛,至10～11月进入蛰伏状态,在土缝、洞隙或枯草叶簇中越冬.当年5月所产卵,从发育成小蛛算起,寿命为120～150 d;7～8月所产卵,发育成小蛛后要在卵袋内越冬,寿命300～360 d.

Initial Observation on Living Habit of Latrotectus tredecimguttatus

The average length of female Latrotectus tredecimguttatus is 10.92mm, the part of head and chest is 4.18mm, and abdomen is 8.19mm. The part of head and chest is shaped like a pear or a jar with colors of brown, purple brown or black. The abdomen is shaped like an egg or a down -peach in black brown. The average length of the male is 4.52mm, the part of head and chest is 2.08mm, and abdomen is 2.82mm, colors of the head and chest are same as those of the female. Its abdomen is shaped like an egg in brown or black. On the back of the front edge, there is a concave arc spot, followed with yellow spots in 3 rows and 4 lines. Latrotectus tredecimguttatus lives in undeveloped bard or farmland, netting irregularly near the surface of the earth in the cap of stones, by the hole and under some short brushes to capture various insects, mostly Orthopteran and Coleoptera.Latrotectus tredecimguttatus mates during May and June. While mating the male and the female are in the posture of abdomen to abdomen, their heads and tails are in the same direction hanging down from the net. The male mates with its left and right antenna in turn. The whole process lasts roughly for 1.5h, then the male leaves immediately and the phenomena of the female chasing and killing the male is not found. The female lays eggs from May to August, during which the period of July and August reaches the high peak. The shape of egg bag is like a sphere, somewhat like a peach, its colors ranging from hazel to brown and the bag's wall is rather thick, whose inside layer covered with white downy silk, and average volume is 13.2 mm×12.0 mm×11.6 mm. Each bag contains 201.1 eggs. A mother spider nets about 2.68 egg bags, and lays totally about 539 eggs. It is in about 30d that those eggs laid during the period of May to July can grow up to baby spiders, and then walk out of their egg bags. Those eggs laid during the period of July to August can also grow up to baby spiders, but they don't leave from their egg bags until March to April of the next year. They must stay there to pull themselves through winter.During the period of September and October, most of the adult female fed indoors gradually die, the female to survive the winter have not been found.The baby spiders hatched during July and August enter hibernation in October or November, and survive the winter in cap of soil, by hole or under hay or defoliation. From the time when they grow up to little spiders, the life span those eggs laid in May is estimated to be about 120～150 d; that of those laid during July to August, which must stay in egg bags to survive the winter, is about 300～600 d.