THE LIFE-HISTORY OF BADUMNA-CANDIDA (ARANEAE, AMAUROBIOIDEA)

A two-year study of the social spider Badumna candida at Townsville, Q ueensland, provided information on colony size and changes over time, maturation synchrony, temperature effects on development, sex ratio, d ispersal, colony foundation, fecundity and oviposition. Key findings w ere that B. candida outbred, had an iteroparous egg-production cycle b etween March and October, had an even primary sex ratio and achieved m aturation synchrony by retarding the development of males, which matur ed faster than females at constant temperature. There was no overlap o f generations, the cohort of young from a nest founded by a solitary f emale in summer dispersing the following summer as subadults (females) or subadults and adults (males). These findings confirm the status of B. candida as a periodic-social spider (an annual outbreeder), in con trast to the few known permanent-social spider species whose generatio ns overlap. Cannibalism, normally rare in social spiders, rose to 48% when spiders were reared at a high temperature. This may be evidence t hat volatile recognition pheromones suppress predatory instincts in so cial spiders.