Sunflower-specialist
Guides
Dieunomia triangulifera
Dieunomia triangulifera is a solitary sweat bee (Halictidae) specialized on sunflower pollen. It occurs in the central United States, where it forms large nesting aggregations of up to 150,000 nests. The species exhibits tight phenological synchrony with its host plant Helianthus annuus, emerging and provisioning nests to coincide with peak pollen availability. Males engage in attempted forced matings at emergence, while actual courtship occurs later.