Clue: John Maybury shot Mothra with his Canon SureShot on Rosita Road. Mark Stechbart thought it was a cecropia, but according to Wikipedia, that moth appears no farther west than the Rocky Mountains. Ian Butler says, "That is a Ceanothus Silk Moth, or Hyalophora euryalus. They are sometimes seen in Linda Mar this time of year. I found a live one with broken wing two years ago, and kept it comfortable until it passed away. Now it is tucked away in my closet, and taken out from time to time for show and tell. We are fortunate to have them in our midst!" San Francisco State University biologist and moth expert John R. Blair says, "Ian Butler is correct."