Mayfly Abdominal Appendages

Mayflies (Order Ephemeroptera) are characterised by two or three long threadlike tails (called caudal filaments) borne at the distal end of their abdomen. Function and specialisation of the caudal filaments may vary between different stages of the mayfly life cycle. In the sexual reproductive stage, the caudal filaments may be used in the mating flight where the males generally fly in swarms that undulate in the air.  At some stage of the flight males will 'parachute' through the air with their wings held upwards and their caudal filaments spread in a V-shape. Females fly into the swarm and are quickly grabbed by a male. Mating takes place while in flight and when fertilised, the female will lay her eggs. Males usually die soon after mating while females die soon after they have laid their eggs (oviposition).