Mayflies are around 3/4" and a brown to yellow color. They have a slender abdomen and 4 wings that are held above the body when resting. Their antennae are small and they have 2 or 3 long trailing hair-like tails.
Mayfly eggs are laid over water, and the nymphs are aquatic. Nymphs will eat debris and other small aquatic invertebrates. When adults emerge, they often swarm during mating for a day or two before dying.
Featued image by Benny Mazur