tags: mystery wasp, mexican wasp, wasp, Image of the Day
Here is an image of a critter for which I have no identification. It is a very large wasp (nearly 2 inches in length), which I photographed in Xalapa, Mexico in October of 2006. it is an evil-looking beast, and I'd like to know if any of your readers can give me more information about it. I'd also like to know what significance (if any) there is to the fact that it is holding one pair of its legs up and parallel to the back.
Image: Dave Rintoul, KSU [much larger]
More below the fold ..
I have learned from a local wasp expert that this critter is probably a scoliid wasp, a small family of wasps with about 300 species worldwide. They prey on beetle larva, which they use to provision the young. Below is a recent note from my local expert, who is also trying to come up with an ID for this critter.
Apparently the huge mandibles and leg armature are related to this wasp's habit of digging after scarab larvae. The mandibles are used to dig and the legs to shove the dirt back from the burrow. So the perching posture may have something to do with the adaptation of the legs to earth moving. I
have not seen any info on perching in the little bit of literature on scoliids that I have in my library.

GrrlScientist is an evolutionary biologist, ornithologist, aviculturist, birder and freelance science and nature writer. A native of the Pacific Northwest, she relocated from Seattle to NYC with her parrots after earning a BS in Microbiology (emphasis in Virology) and PhD in Zoology (Ornithology) from the University of Washington. In NYC, she was the Chapman Postdoctoral Fellow at the American Museum of Natural History for two years, pursuing part of her "dream" research project by reconstructing a molecular phylogeny of the parrots of the South Pacific islands. GrrlScientist and her five parrots are currently relocating to Germany, where she will continue writing her blog while also writing a book and learning German. (Meanwhile, her parrots will continue to nibble on her extensive personal library.) If you appreciate GrrlScientist's writing, you can help pay her living expenses by hiring her to "blog" your conference, speak at your club or write articles for your publication (or by clicking on the Paypal button below). If you read an essay on this blog that you especially enjoyed, please nominate it for inclusion in 

























Comments
I'm amazed by the mandibles. That's a pretty cool wasp.
Posted by: IanR | August 6, 2007 5:42 PM
Damn! I'm not going to tell you again. Keep that screen door closed!
Posted by: cfrost | August 11, 2007 5:52 AM
Here that wasps are abundant near sandy beaches, perhaps they had some kind of sensors on the back legs?(ocassionally they vibrate back legs while perching)
Posted by: Edgar | August 20, 2007 2:52 PM