Group structure in a social huntsman spider (Delena cancerides) reveals seasonal variation in group complexity

Sociality in spiders has evolved independently multiple times with diverse expressions. Delena cancerides, an Australian huntsman spider, shows some sociality but has been classified variably as social, subsocial, or non-social. Previous classifications were based on evidence like outbreeding, balanced sex ratios, and colonies primarily consisting of one mother and her offspring. However, studies, including this one, have found colonies with multiple adult females, males, and juveniles at certain times of the year. The data show that D. cancerides colonies were more diverse in summer, with multiple adult females, males, and juveniles, compared with spring, when colonies mainly consisted of one adult female and juveniles. Although all huntsman spiderlings cohabit briefly before dispersing, D. cancerides spiderlings shared prey beyond this period, especially larger prey. This suggests that the species’ social structure is more complex than previously thought, varying with time and possibly related to colony composition, warranting further study.