Appearance
The adults grow up to 10–25 millimetres long, the body is completely black, with two glossy yellow stripes on the adbomen. The wings have a smoky-dark color, with blue reflexes. Males have longer antennae than females, as well as three large spines at the tip of their abdomen.They can be encountered from July through September feeding on flowers, with a preference for flowers appearing cyan or blue to bees eyes and for composite flowers or aggregated inflorescences.

Behavior
These massive solitary wasps dig in search of larvae of beetles. Then they parasitize the larvae and lay eggs in them for feeding their offspring.References:
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