Squash Vine Borer

clearwing moth question/answer
Hello fellow bug-lovers!
The moth Valerie from Ontario asked about looks an awful lot like the "squash borer moth" that attacks our garden plants (see attached). These buggers lay their eggs in the stems of the fruits of squash, pumpkins, and the like, and their caterpillars consume the interiors of the stems until there’s no surviving fruit. I think they pupate in the soil. I’m not sure of the species, but they are a very interesting pest. I live in Central Minnesota.
Don Dinndorf
St. Augusta, MN

Hi Don,
The moth in your photo is a Squash Vine Borer, Melittia satyriniformis, and what you say about it is true. The photo that Valerie sent is not quite as sharp as your image and makes exact identification difficult, but we can say with some certainty that they are two different, though related species. Clearwing Moths in the family Sesiidae are Wasp Mimics. The caterpillars from this family are borers in the stems, roots and bark of various trees and other plants, and some can do considerable damage.

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