机敏异漏斗蛛的生活史及各虫态的形态特征

The life history and morphogical characteristics of Allagelen difficilis

机敏异漏斗蛛Allagelena difficilis是我国常见蜘蛛,在自然生态系统的害虫控制中起重要作用。野外调查结合室内饲养观察,弄清机敏异漏斗蛛的生活史及各龄虫态特征。机敏异漏斗蛛一年1代,蜕6次皮,以成蛛、卵和1龄幼蛛越冬,翌年4月上旬在蛛网上可以见到活动的2龄幼蛛,8月中旬发育为成蛛,由卵到成蛛平均历时265 d。卵椭球形,黄色;1-3龄幼蛛体光亮,枣红或红褐色;3龄幼蛛腹部背面隐约可见四对"八字形"灰白斑纹;4-6龄幼蛛体表光泽不明显,"八字形"灰白斑纹明显;6龄雄蛛触肢开始膨大而透明,雄性成蛛触肢膨大且色深。各龄虫态步足足式均为:ⅣⅠⅡⅢ。

Allagelen difficilis（ Fox） is common to be seen in China. They play an important role in pests＇ control of natural ecosystems. We combine field survey with indoor rearing to investigate its life history and the characteristics of each instar. A. difficilis produces one generation per year and developed into adults after 6 molts. This spider overwinters as adults,eggs and 1stinstar spiderling. In early April of the following year after hatching,the 2ndinstar was seen on the surface of the cocoon. They develop into adults in mid- August. A. difficilis requires a mean developmental period of 265 days from eggs laying to maturity. The eggs are ellipsoidal and yellow. The body of 1st- 3rdinstar spiderling is bright,maroon or brown. Four pairs Splayed grey stripes were seen on the back of abdomen of 3rdinstar spiderling. The brightness disappears and Splayed grey stripes become more obvious during the period of their 4th-6th instar. The pedipalps of the spider will enlarge and are translucent,when the male is 6thinstar,and then become black as adults. The leg formula of each age instars is： ⅣⅠⅡⅢ.