mud dauber

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of various solitary predatory wasps, especially of the families Sphecidae and Crabronidae, that build nests of mud and provision them with paralyzed prey.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun wasp that constructs mud cells on a solid base in which females place eggs laid in paralyzed insect larvae