The biology of a Patellapis (s. str.) species (Hymenoptera : Apoidea : Halictidae): sociality described for the first time in this bee genus

The sweat bees are socially diverse and therefore make ideal subjects for the study of insect sociality. A small nest aggregation of an undescribed species of Patellapis (s. str.) was studied in the western South African winter rainfall area to provide information on nest architecture, floral hosts, seasonality and kleptoparasites. A single excavated nest was inhabited by eight females and consisted of a main burrow with several lateral tunnels. Observations indicate that this Patellapis species probably has a communal nesting behaviour; sociality is recorded for the first time within this bee genus. Analyses of provisioned nest cells and scopal pollen loads of females revealed that this species is polylectic (generalist), collecting pollen from plant species occurring in high abundance, namely Asteraceae, Zygophyllaceae and Oxalidaceae. The species is parasitized by the cuckoo bee Sphecodopsis semirufa (Cockerell), which is recorded for the first time to attack a halictid bee.