The male patrols patches of flowers of the Lamiaceae  (woundworts, dead nettle) family and Scrophulariaceae (foxgloves, toadflax) family. Darting at any insect that strays into its territory. It often grapples other bees or other males to the ground and uses spikes at the end of its abdomen as a weapon against intruders. Females are allowed access to the territory, where they can feed from fresh flowers.

Left: Spikes on male abdomen

Females look similar, but are smaller than males and do not have the spikes on the abdomen. They collect hairs from plants which they use to seal cells in holes in timber, containing their offspring.

Left: Female collecting plant hairs

Status: Locally common across much of southern England and Wales. Often found in gardens where lamiates grow.

Flies Late May to early August.

More photos here