I spotted this checkerspot butterfly while hiking the Big Rock trail in Lucas Valley, Marin county, with my friend Jean in May. A few days later I spotted another — just like it? — outside my kitchen window, but it disappeared before I could grab the camera. There are several kinds of checkerspots in the San Francisco Bay Area. I’m thinking this one is the bay checkerspot, which is listed as endangered.

And . . . that’s a blue dick serving up nectar to the butterfly.

I notice that I’ve been photographing a lot of insects lately.

• A humongous dragonfly, spotted in my front yard, about 3 1/2 inches long, feasting on lavender and coexisting with a bee just inches away.
• Houseflies caught between the screen and window in my kitchen.
• Gnats (fruit flies?) on a blousy white poppy.

For another nature story, go to “The Trouble With Daffodils.”