Gonzaga Marcelo O, Sobczak Jober F
Departamento de Zoologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.
Naturwissenschaften. 2007 Mar;94(3):223-7. doi: 10.1007/s00114-006-0177-z. Epub 2006 Nov 21.
All species included in the Polysphincta genus-group develop as ectophagous parasitoids of active spiders, killing their hosts prior to pupation. However, little information regarding natural history and ovipositing behavior of most species are available. In this study we inspected 85 webs of Araneus omnicolor to evaluate the frequency of parasitism and host size preferences of the wasp Hymenoepimecis sp. We also described the web characteristics of normal and parasitized spiders and the wasp ovipositing behavior. About 41% of the adult females of A. omnicolor inspected were parasitized. The highest incidence of parasitism was observed among relatively small females while no egg or larva was found in large individuals. Araneus omnicolor builds a strong web composed of an orb and barrier threads, where the spider rests within a curled leaf. The parasitoid larva builds its cocoon within this refuge, and modified cocoon webs were not observed. The ovipositing behavior of Hymenoepimecis sp. was very similar to that of Hymenoepimecis argyraphaga parasitizing Leucauge argyra, including the position of the sting, the killing of a previously attached larva, and the expelling of the egg from the base of the ovipositor.
多斑蛛属类群中的所有物种均发育为活跃蜘蛛的体外寄生性天敌，在化蛹前杀死其宿主。然而，关于大多数物种的自然史和产卵行为的信息却很少。在本研究中，我们检查了85个全色园蛛的蛛网，以评估黄蜂类胡蜂的寄生频率和宿主大小偏好。我们还描述了正常蜘蛛和被寄生蜘蛛的蛛网特征以及黄蜂的产卵行为。检查的全色园蛛成年雌蛛中约41%被寄生。在相对较小的雌蛛中观察到最高的寄生发生率，而在大型个体中未发现卵或幼虫。全色园蛛构建由圆形和屏障丝组成的坚固蛛网，蜘蛛在卷曲的叶片内休息。寄生幼虫在这个庇护所内结茧，未观察到经过改造的茧网。类胡蜂的产卵行为与寄生银斑亮腹蛛的银斑类胡蜂非常相似，包括蜇刺的位置、杀死先前附着的幼虫以及从产卵器基部排出卵。
