Chalybion Wasp with its prey.

seen from Germany
seen from United States

seen from United States
seen from China

seen from Estonia
seen from United States

seen from United States
seen from France

seen from Malaysia

seen from Germany

seen from Malaysia
seen from United States
seen from France

seen from United States
seen from United States

seen from Malaysia

seen from Spain
seen from United States
seen from United States
seen from China
Chalybion Wasp with its prey.
Blue Mud Dauber (Chalybion californicum) -
This species of wasp is known for building nests out of mud. The females build these nests in cylindrical tubes. Some species of mud daubers build long, elegant, pipe shaped nests along walls or ceilings of various structures and caves. Others build clumps of tubes, and cover them in mud, each tube having one egg.
Blue mud daubers will inhabit the abandoned nests of the other species. They bring their own water and mud to adjust and repair these old nests. Females will hunt for the nest, while males will guard and occasionally bring food. They are the main predators of brown and black widow spiders. Adults will drink flower nectar, but the hatchlings will eat spiders brought to them by their parents.
The wasp will sting its prey, paralyzing it, keeping it alive to feed the larvae. It is not aggressive and will rarely sting a human. They are quite common throughout the united states. The blue mud dauber particularly likes the dry west coast where its favorite prey is common.
Photos: (top) (bottom left) (bottom right)