Angol leírás, sztori

"Palingenia longicauda is an aquatic insect in the order Ephemeroptera. It is known as the Tisa or Tisza mayfly after the European Tisza river where it is found and also as the long-tailed mayfly and giant mayfly since it is the largest mayfly species in Europe, measuring 12 cm (4.7 in) from head to tail.
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Large numbers of P. longicauda larvae will usually hatch and mature during a week in mid June; this natural phenomenon is known as the 'blooming of the Tisza' or 'Tisza blooming' and is a tourist attraction. Adults hatch two times in a short period of time. After hatching the adults only have a few hours to mate before they die..."