Commonly known as the Green Drake mayfly, this species of mayfly is one of the biggest and well known species. The adults have three tails and large hindwings. The aquatic larval form inhabits unpolluted waters such as lakes and fast flowing rivers and streams. The nymphs dig into gravel and sand to make a tubular burrow where they use their gills to move water through it. Therefore they inhabit water bodies with gravel or sandy beds. They feed on small particulate detritus from the water by filter feeding. The species will spend up to two years in this larval form but the lifecycle can be as quick as one year in the warmer climate of Southern England. This species is found in rivers and lakes throughout nearly all of the British Isles. It is less common in the far north.
