Possible Functions of the Detritus Stabilimentum and Hanging Detritus in Webs ofAzilia vachoni(Araneae: Tetragnathidae)

Abstract

Summary Many orb-web spiders include silk stabilimenta in their webs. This conspicuous web feature has led to many studies on their designs and possible functions. However, the same cannot be said for the less conspicuous detritus stabilimenta included in the orb webs of some species, and is a characteristic feature of some genera. The orb-web spider Azilia vachoni constructs detritus stabilimenta and suspends debris under its web. Observations were carried out in 17 primary and three disturbed habitats on the island of Trinidad, West Indies. Out of the 144 webs observed, these structures were recorded in 11 natural and one disturbed habitat, all of which had closed canopies. This preference of this species for buttress notches (the semi-open space between two buttress roots) suggests that it additionally relies on this microhabitat for concealment. This study examined possible functions and reasons for the inclusion of these features in the webs of this species. The age of individuals was taken into acco...