(Black and yellow) Dull black with parts of body being bright yellow with long, thin waist, dark wings, and 1/2 to 1/8 inch long.
(Blue) Dark metallic blue to black wasp with long, thin waist, 1/2 to 1 inch long, with bluish wings.
Females collect mud with their mandibles. They then use mud to form cylindrical shaped nests on walls or sides of equipment or use a previously constructed nest. They collect food and lay an egg on the prey within each cell and seal the cell with mud. The female then leaves the nest at the end of spring. When the new adult wasp emerges from the cell the cycle begins again.
Mud daubers are considered beneficial since they kill spiders and pose none or little harm to humans.
Rarely aggressive and stings are very uncommon.
They build tube like nests that are attached to crevices, cracks and corners. Also occupy barns, porches or other nest sites.