Nest of the Social Spider Phryganoporus-Candidus (Araneae, Desidae) - Structure, Annual Growth-Cycle and Host-Plant Relationships

Abstract

Aspects of the biology of the social spider Phryganoponrs candidus (=Badumna candida) (L. Koch) in relation to its life history are described, based on data from a field and laboratory study conducted over several years at Townsville, Queensland. Host plant records and preferences are given, and an analysis made of the effects of nest height and ecotone proximity on nest occurrence. Founded between October and February as a chambered silk funnel by a solitary subadult female, the nest was enlarged by the female and her progeny into a complex retreat area and an outlying prey-trapping area. The architecture of the retreat was not an aggregation of repeated subunits. Closely adjacent nests sometimes united their prey-capture webbing to form compound nests. From a tagged sample of new-founded nests, 31% reached a stage at which thriving spiderlings were present. Numbers of spiders in nests ranged from 9 to 224 and correlated with nest size, which ranged from 70 to more than 20 000 cm(2). At the peak of nest growth in October, the stage at which subadult spiders began to disperse, about 90 spiders inhabited each nest; only 12% of new-founded nests reached this stage. Summer dispersal left nests empty; they degenerated under rain and became moribund by March. The main host plants were Zizyphus mauritiana (the chinee apple) and Dolichondrone heterophylla. Most nests occurred between 0.5 and 2.5 m from the ground but height did not influence nest success. Nests were prevalent at ecotones, although they did not thrive better there. Because so much of the social biology of spiders is integrated with the structure and function of their nests, these findings are relevant to an understanding of the evolution of sociality in spiders.