Size, Shape and Colour: Approximately 5mm to 2cm from head to base of tail in size. Mayflies can be recognised by their short antennae, and either two or three long tail filaments. Their wings are held vertically over their backs when resting. The hind wings are much smaller than the forewings.
Biology: Many species of Mayfly only live for one day! The eggs of mayflies are laid underwater, and the nymphs which hatch from the eggs live for two years in the water. Then on a bright sunny day, normally between May and July the nymph emerges from the water, and the adult mayflies break out of their larval cases. From this moment on, the mayflies have just hours to live. They quickly take to the air in a hurried search for mates. Once mated, the males die. The females lay their eggs in the water and then they die too.
Preferred Foods: The adult Mayflies do not feed. The nymphs feed on organic detritus and gather their food by scraping it together.
Habitat: The nymphs are known to occupy riffles and shallows in lowland areas of large, clean rivers.