Girdle on a mesquite twig created by Oncideres rhodosticta. Arroyo Chico, Tucson, Pima County, Arizona, USA. 18 October 2008.
When you see a fresh girdle like this, there are likely mesquite girdler eggs in the distal part of the twig. The mother beetle chews this ring around the twig so the tip of the twig dies and the tree's resin cannot drown her offspring. The grubs develop in the dead twig and usually also pupate and overwinter in it.
Arroyo Chico, Tucson, Pima County, Arizona, USA. 18 October 2008.
Sign of mesquite girdler, Oncideres rhodosticta. Arroyo Chico, Tucson, Pima County, Arizona, USA. 18 October 2008.
Pupae of braconid wasps. Arroyo Chico, Tucson, Pima County, Arizona, USA. 18 October 2008.
I found lots of these in a thicket of climbing milkweed (Funastrum cynanchoides) that was frequented by queen butterflies (Danaus gilippus) earlier in the year. I suspect that these wasps emerged from queen caterpillars.
Hylephila phyleus. University of Arizona Campus, Tucson, Pima County, Arizona, USA. 18 August 2008.
