Coelioxys

Coelioxys are dark, medium-sized cuckoo-bees. They are a nearly cosmopolitan group that can be found in several habitats across the world. Both sexes have hairy eyes and conspicuous bands or patches of appressed hair across the abdomen. They can be differentiated from other bees by their distinctive "keel-like" abdomen, which narrows progressively towards the end. Females have a pointy tip at the end of the abdomen while males have a set of spines. Typically, they are brood parasites of Megachile bees, but they can also occasionally attack other megachilids. Females can be found around to the nesting areas of the host looking for unattended nests. They insert their long, sharp abdomen throw the walls of the burrow and then lay an egg directly on the food provisions of the brood cells. Upon hatching, the larva destroys the offspring of the host and consumes the provisions.