The life cycles of mayflies (Insecta: Ephemeroptera) of the Eastern Ukraine. Second report

Abstract

The Life Cycles of Mayflies (Insecta: Ephemeroptera) of the Eastern Ukraine. Second Report.-Martynov, A. V.-This article is the second report on the results of investigation of mayflies' life cycles in Eastern Ukraine. It is shown, that different methods should be used to determine the larval age of the representatives of different families. The paper presents data on life cycles of 18 mayfly species; the larval age structure change during a year for five of these species (Cloeon dipterum, Centroptilum luteolum, Paraleptophlebia submarginata, Ecdyonurus dispar gratificus and Ephemera vulgata) was investigated in detail in model waterbodies. The flight periods of imagoes of investigated species within the Eastern Ukraine are given. Some features of swarming in Leptophlebia marginata and Kageronia fuscogrisea are described. It is shown, that rare European species Metreletus balcanicus has monovoltine life cycle within the region, and overwinters at the egg stage (Us). It is established, that ovoviviparous Cloeon dipterum has 2-3 generations per year (MB-MP) within Eastern Ukraine; the voltinity depends mainly on water temperature in every concrete waterbody. The main part of population of monovoltine Ecdyonurus dispar gratificus overwinters as the egg stage, small its part-as the larval stage.