A bluish butterfly caught my eye in the main vegetable garden yesterday, near the base of the tomato plant that I had just finished watering. It (s/he) was methodically getting moisture and nutrients from the damp mulch, opening and closing its wings in a typical fashion. I was hopeful it was a pipevine swallowtail (I REALLY need caterpillars on the big pipevine to do some pruning (that is, chomping!), but it turned out to be a pipevine mimic, a red-spotted purple.
Mimicking the distasteful pipevine (because of the aristolochic acids sequestered from its host plant) helps reduce predation, since birds quickly learn to avoid them.
This one spent quite a bit of time 'puddling' before heading off.