Phenology of two bee genera and a fly
Phenology of the genus Andrena and of its cuckoo bee Nomada, and also the parasitic beefly Bombylius. Information collected from Bugguide submissions up to March 2011
The cycles of the two parasitic species (bee and fly) follow that of this host species reasonably well. They also use other hosts. Nomada parasitizes Andrena and also Agapostemon and Eucera. Bombylius uses Colletes and Halictus bees as hosts in addition to Andrena. This may account for the rather large numbers of the parasitic bees and flies when compared to those of this particular host.