It is a black wasp with a long, thin waist, and is not a social wasp. It is not very aggressive and does not sting people often. However, its mud nests are often built close to human actively. The mud dauber constructs brood chambers from mud on the sides of the buildings and under eaves. The wasp stings and paralyzes spiders, lays an egg on them, and seals them inside the chambers. The wasp larva hatches and feeds on spiders. An emergence hole in the mud means that the wasp has emerged from the chamber.