Manipulation of araneid spider web architecture by the polysphinctine parasitoid Zatypota picticollis (Hymenoptera: Ichneumonidae: Pimplinae)

Abstract

We found that the koinobiont ectoparasitoid wasp Zatypota picticollis is exclusively associated with three orb weaving spiders Cyclosa conica, Mangora acalypha and Zilla diodia from the family Araneidae. Under the influence of the parasitoid's final instar larva the spiders built a specific web architecture, which differed considerably from the capturing orb web. Manipulated webs of C.conica and M.acalypha lacked the spiral, stabilimentum and central hub, and the radials were reduced in number. The manipulated web of Z.diodia consisted of one strong horizontally oriented thread.