KIN ASSOCIATION IN THE ALLODAPINE BEE EXONEURA-RICHARDSONI RAYMENT (HYMENOPTERA, APIDAE)

Exoneura richardsoni is a common allodapine bee which, in southern mon tane Victoria, primarily nests in dead fronds of tree ferns. We sample d intact colonies from the Dandenong Ranges from August 1992 through t o February 1993. The bee is univoltine, with egg production commencing in later winter and adult eclosion occurring over summer. The majorit y of colonies in both re-used and newly founded nests contain more tha n one female. Intra-colony relatedness is very high (r = +/- s.e., 0.7 59 +/- 0.087) in re-used nests and moderately high (0.498 +/- 0.152) i n newly cofounded colonies, indicating maintenance of kin integrity du ring nest re-use and kin recognition during foundress association. Thi s is only the second time that kin cofounding has been demonstrated in a primitively social bee species. Samples during winter and early sum mer show that per capita brood production increases with colony size u p to about 3 or 4 females per nest, and this may explain the high degr ee of social nesting in this species. Whilst eusociality could occur i n some nests, the opportunities for older, adult brood members to help rear younger siblings are very limited. It seems likely that in E. ri chardsoni and at least some other Australian allodapine bees, the sele ctive maintenance of high levels of social nesting and kin recognition does not depend on the existence of eusociality.