The Striped Mayfly is one of Britain’s rarest mayflies.
Like all mayflies the Striped Mayfly spends most of its life under water as a nymph, emerging as an adult in the summer. The nymphs grow up to 35mm and are cream coloured with dark markings and three long tails. Adults are up to 30mm in length and have two pairs of wings; strongly veined transparent front wings and a smaller pair of rear wings. Adults are usually seen emerging from the water in July.
Striped Mayfly nymphs live in the pools and margins of large rivers. They dig tubular burrows in the substrate and feed by filtering fine particulate organic detritus from the water column.
Distribution and threats
The Striped Mayfly is currently listed as Vulnerable in the Red Data Book for Great Britain. They are the rarest species of British mayfly. They are currently known to occur in the River Thames and the River Wye. Threats include loss of habitat and pollution.