It was dusk, and the lure of the gas station lights was too tempting for this beauty -- a mayfly larva rose to the surface of the nearby Black River, split her outer skin while attached to the surface tension, and rose up with newly-formed wings toward the lights. I found her like this, only recently emerged from her first adult skin (sitting empty next to her), poised and ready for takoff. I beleve this is the female of the species "Hexagenia limbata," a mayfly that burrows in the sediment in the bottom of slow-moving rivers -- an excellent indicator of high quality water!
Mayflies are insects of the order Ephemeroptera, which means "short-lived" -- and they live up to that name! After living their entire juvenile lives underwater (for some species, that's years!), mayflies emerge in one night and live rarely more than 24 hours. They don't even have time to eat, so any mouthparts on the adult mayfly is non-functioning. They emerge, molt, mate, and die, often by the millions at a time in one location.
Many fishemen know this emergence as "the hatch" -- although the little larvae hatched from their eggs months or years prior to emerging from the river as aerial adults. Occasionally, an emergence will be so massive and dense that it actually appears on Doppler radar!