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Species Chalybion californicum - Common Blue Mud-dauber Wasp

Spider hunter - Chalybion californicum Chalybion californicum sphecid - Chalybion californicum Wasp23 - Chalybion californicum Hymenoptera - Chalybion californicum Chalybion californicum? - Chalybion californicum - female Metallic Blue Wasp:  Chalybion or Chlorion? - Chalybion californicum maybe Sphex pensylvanicus ?? - Chalybion californicum - female
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
No Taxon (Apoid Wasps (traditional Sphecidae))
Family Sphecidae (Thread-waisted Wasps)
Subfamily Sceliphrinae
Tribe Sceliphrini (Mud-dauber Wasps)
Genus Chalybion (Blue Mud-dauber Wasps)
Species californicum (Common Blue Mud-dauber Wasp)
Other Common Names
Common Blue Mud Wasp
Common Blue Dirt-dauber Wasp
Nearctic Blue Mud-dauber Wasp (primarily outside of our area, where another member of the genus is "common")
* Note: this species should not be called "the" blue mud-dauber or "the" blue mud wasp as those apply to the entire genus.
Synonyms and other taxonomic changes
Chalybion californicum (de Saussure, 1867)
Pelopoeus califortiicus de Saussure, 1867
Sphex cyanea Fabricius, 1775
Sphex caerulea Linnaeus, 1763
Sphex caeruleus Linnaeus, 1763
Explanation of Names
CALIFORNICUM - from the New Latin californicum ('Californian, of or from California')
10-23 mm
A large, active, blue-black wasp with irridescent blue wings. Frequents flowers for nectar and buildings for nest sites. Compare "Steel-Blue Cricket-hunter Wasp" Chlorion aerarium, which preys on crickets. This is about the same size as Chalybion, and is said to have a longer pedicel (narrow waist between thorax and abdomen). The body of Chalybion looks much more hairy, and more steely-blue, based on specimen photos.
Widespread in North America (1)(2)(3)
Fields with flowers; residential areas
Apr-Oct in NC
Adults take nectar. Larvae feed on spiders.
Life Cycle
Females construct mud nests in sheltered areas, often under the eaves of buildings, and provision them with spiders. Sometimes refurbishes the nests of other mud-daubers, such as Sceliphron.
Probable nests:

Here are some females with prey:
Print References
Works Cited
1.Catalog of Hymenoptera in America North of Mexico
Karl V. Krombein, Paul D. Hurd, Jr., David R. Smith, and B. D. Burks. 1979. Smithsonian Institution Press.
2.BOLD: The Barcode of Life Data Systems
4.A Field Guide to Common Texas Insects
Bastiaan M. Drees, John A. Jackman. 1998. Gulf Publishing.
5.Ascher J.S., Pickering J. (2017) Discover Life bee species guide and world checklist (Hymenoptera: Apoidea: Anthophila)