Dave casually mentioned seeing it after coming in from putting out the trash. I jumped up, exclaiming "WHERE!!!", grabbed my camera, and ran out to see. He was bemused at my excitement, since it was so drab and tiny (a mere 2 inches long) compared to the 6-inch colorful mantises he was used to seeing growing up in Maui.
It turns out there is a species of praying mantis native to California (stagmomantis californica). I found a web page by someone who lives about 70 miles north of us who regularly sees tons of them, mostly during the fall mating season. He even has a few photos of decapitated males (ugh!).
Speaking of "ugh", can you imagine living in a place where 2-inch insects are considered tiny? Then again, growing up on a small farm in Southern California, I am unfazed by snakes and black widow spiders (which are exotic to Hawaii people).