Primitively Eusocial Behavior Observed in Colonies of Augochlora amphitrite (Hymenoptera: Halictidae) Reared in Laboratory

The present study provides evidence of primitively eusocial behavior in Augochlora amphitrite (Schrottky). Bees were reared in laboratory nests and observed throughout their nesting cycle. Introduced foundresses constructed nests solitarily, but upon the emergence of the first daughter their activities changed drastically, marking the onset of a social phase. The colonies presented two well defined female castes according to their physiology, size and behavior. Foundresses monopolized oviposition, displayed low rates of nest construction, guarding, and pollen collection, they were the individuals that initiated social interactions, and were statistically larger. Daughter bees were smaller, with undeveloped ovaries, performed most tasks at the nest and were the subordinate individuals in social interactions.