Flavous nomad bees are solitary bees, and look quite wasp-like.
They are cleptoparasites, which means that they lay eggs in the nests of another bee, in particular, the nests of mining bees (Andrea spp.). For this reason, they can be referred to as cuckoo bees. When the cuckoo bee larva develops, it kills the host larva and then feeds off its pollen provisions.
Look out for them hanging around mining bee nests in the Botanic Garden.