A remarkable scene. By the end of the afternoon a group of Common furrow bee (Lasioglossum calceatum) males converged on a Verbena flowerhead (Verbena bonariensis).
It looked like a social setting where they were all relaxed and grooming themselves without any real interactions between the inidviduals. I haven’t been able to observe whether they drank nectar. Looking at the rather deep flowers I assume their tongues are not long enough to reach the nectar.
In the end I have counted eight individuals.