Cuckoo Wasp

Brilliant Blue Bugger
Location: North San Francisco Bay Area, Inland
January 27, 2012 9:48 pm
I’ve searched your site, and the net in general, but haven’t found a good match for the subject of my attached image, recorded May 7, 2011 in mid-afternoon. Taken in macro mode, when viewing ”actual pixels” the effective magnification is about 4.5X. Body length, excluding legs, is 13/32” ±1/32, or about O.40”.
Our photogenic friend’s carapace has an irridescent metallic sheen that can range from royal blue to teal to green. Here it appears to be royal blue with light blue speckles on the top, while it’s lower hemisphere is teal. At other angles the body appeared green and the tail blue.
Might this be a wasp of some sort?
Signature: zzwerzy

Cuckoo Wasp

Dear zzwerzy,
While it is an easy enough matter for us to identify your lovely insect as a Cuckoo Wasp in the family Chrysididae, it is quite another matter for us to be able to provide you with a species identification.  According to BugGuide:  “they are most diverse in the west: 166 spp. are found in CA alone (10% of all our spp. are CA endemics)” and we haven’t the necessary skills to differentiate between the species. 
BugGuide also states:  “The name ‘cuckoo wasp’ refers to the fact that these wasps lay eggs in the nests of unsuspecting hosts”  and clarifies that with this information:  “Parasitoids feed on the larva of the host and cleptoparasites ‘steal’ the host’s food. The food-stealing behavior of cleptoparasite species resembles that of the cuckoo bird and gave rise to the cuckoo wasp’s name. Hosts of parasitoid species include bees, sphecid wasps, potter wasps, sawflies, silk moths, and the eggs of stick insects. Cleptoparasitic species feed on provisions of sphecid wasp nests, which may include dead spiders, true bugs, aphids, or thrips.” BugGuide describes Cuckoo Wasps as having a “Body metallic blue or green, usually with coarse sculpturing (many pits in surface).” 

3 thoughts on “Cuckoo Wasp”

    • There are Cuckoo Wasps in your area and it probably accidentally found its way into your home. Just trap it in a glass, slide a postcard under the opening of the glass and release the Cuckoo Wasp outside.


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