Ontogenic time and worker longevity in the Australian stingless bee, Austroplebeia australis

Little is known about the biology and life cycle of the Australian stingless bee, Austroplebeia australis (Friese). The ontogenic times for developing offspring, as well as the longevity of adults, drive the overall life cycle of a social colony. The developmental times for brood within stingless bee species which build cluster-type nests, such as A. australis, are as yet unreported. A technique was developed whereby 'donor' brood cells were separated from the main brood cluster and 'grafted' into hive annexes, allowing workers from within the colony to access the brood 'grafts' for hygiene and maintenance activities, whilst enabling observation of developing brood. The mean ontogenic time for A. australis workers, maintained at ~27 °C, was 55 days, which is similar to that reported for other stingless bees. The maximum longevity of A. australis was determined by marking cohorts of worker bees within five colonies. Workers within all colonies demonstrated extended longevity, with an overall maximum longevity of 161 days, with the oldest bee living for 240 days. Extended longevity may result from evolutionary adaptations to the floral resource scarcity, which is regularly experienced in semi-arid, inland Australia, the natural habitat of A. australis.