1/500 shutter speed wasn't enough to "stop action".
Have observed these several times, usually at dusk.
Lepidoptera (/ˌlɛpɨˈdɒptərə/ lep-i-DOP-tər-ə) is a large order of insects that includes moths and butterflies (both called lepidopterans). It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies. The term was coined by Linnaeus in 1735 and is derived from Ancient Greek λεπίδος (scale) and πτερόν (wing). Comprising an estimated 174,250 species, in 126 families and 46 superfamilies, the Lepidoptera...