Web-sharing Sociality and Cooperative Prey Capture in a Malagasy Spitting Spider (Araneae: Scytodidae)

Web-sharing sociality and cooperative prey capture are reported for Scytodes socialis, sp. nov., a spitting spider discovered in a dry deciduous forest in Eastern Madagascar. Transect-based sampling was used to investigate colony demographics, estimate web volume and stratigraphic position, and assess density of colonies at the study site. The social system in S. socialis is compared to that of other non-territorial social spiders where multiple juveniles and adults of both sexes live in colonies while maintaining an unbiased sex ratio. While this form of sociality is previously undocumented in Scytodidae, a variety of social systems is found within the family. With future advances in phylogeny, Scytodidae may become a useful system for studying the evolution of sociality including an independent test the “maternal care pathway” to sociality hypothesis.