This group of wasps gets its common name from the fact that they construct their nest of
mud. They are typically nuisance pests. Mud daubers are found throughout the United
Adults mostly about 1/2-1+" (12-25+ mm) long, slender. Color usually black, may have
pals markings or a metallic luster. Thorax with pronotum collarlike. Wings clear or dark;
front wing with 1 or 3 submarginal cells. Abdomen either very slender or petiolate
Other sphecid wasps (Sphecidae) do not make mud nests and either with
more than 1 submarginal cell in front wing and eyes not notched on innermargin or 1 tooth
on front tarsal claws, middle tibia with 1 apical spur, and usually both recurrent veins
meet 2nd submarginal cell of front wing.
Paper (Polistes spp.) and some potter wasps (Eumenes spp.) with
pronotum in lateral view almost triangular, extending to tegulae (structure at base of
front wing) or nearly so, 3 submarginal cells in front wing, and 1 st abdominal segment
conical, not stalklike.
Organpipe mud daubers; subfamily Trypoxyloninae. Mostly about
1/2" (13 mm) long; color black; head with inner margins of eyes notched; front wing
with 1 submarginal cell, marginal call pointed apically; and make long (up to 8+"/20+
cm) tubular mud nests provisioned with spiders.
Black-and-yallow mud dauber, Sceliphron caementarium (Drury);
subfamily Sphecinae. About 1/2-1 1/8" (14-28 mm) long; color dull black with antennal
bases, prothoracic collar, scutellum, portion of metathorax, petiole, and parts of legs
bright yellow; 1 tooth on front tarsal claws, middle tibia with 2 apical spurs; front wing
with 3 submarginal cells, both recurrent veins meet 2nd submarginal cell; abdomen stalked
at base, petiole long; and make short tubular mud nests plastered over with mud,
provisioned with spiders.
Blue mud dauber, Chalybion califomicum (Saussure); subfamily
Sphecinae. About 1/2-3/4" (12-18 mm) long; color metallic blue, blue-green, or
blackish with bluish wing$; 1 tooth on front tarsal claws, middle tibia with 2 apical
spurs; front wing with 3 submarginal cells, both recurrent veins meet 2nd submarginal
cell; abdomen stalked at base, petiole moderate in length; and does not make a nest of its
own but instead is dependent on those of black-and-yellow mud dauber (S. caementarium),
discarding the original nest contents, then adding its own spiders and eggs.
Mud daubers are solitary wasps, they are not social and do not live in colonies. The
aphecinae mud daubers overwinter as full-grown larvae, pupate in the spring, and emerge
shortly thereafter. Females construct nests of mud. Many short mud tubes/cells, usually
about 1" (25 mm) long, are constructed side-by-side. Each cell is provisioned with
several spiders which she has paralyzed with her venom, with the first spider in having an
egg deposited on it. Eventually this mass of tubes is about 3-4" (7.6- 10 cm) in
diameter and is entirely plastered over with mud. The female then selects another site and
starts over. A larva can complete its development in about 3 weeks, then spins a silken
cocoon but does not pupate until the following spring. Females typically provision their
cells with only one kind or group of spiders.
Mud daubers do not defend their nests, and only rarely sting.
Mud daubers typically select a sheltered site to build their mud tubes. Favorite sites
include under eaves, porch ceilings, in garages and sheds left open, in barns, protected
building walls, in attics, etc.Nests typically exhibit round holes in them as the wasps
emerge. This means the nest is probably old and inactive after springtime.