Dragonfly assemblages in the upper parts of the River Tisza: a comparison of larval and exuvial data in three channel types

Abstract

We studied dragonfly assemblages in the Ukrainian section of the River Tisza, which still shows several natural (unregulated) properties. In 2010 and 2011 larvae and exuviae were collected in the vicinity of the villages Vilok (Вилок, Tiszaújlak), Nove Szelo (Нове Cело, Tiszaújhely), Tiszobikeny (Тисабикень, Tiszabökény) and of the towns Vinohragyiv (Виноградiв, Nagyszőlős) and Huszt (Хуст, Huszt). We collected our samples from 8 sites in the main channel, 2 sites in side channels and 3 sites in two dead channels. We collected 255 larvae and 1587 exuviae, from which 8 species of dragonflies were identified [Gomphus vulgatissimus (Linnaeus, 1758), Stylurus flavipes (Charpentier, 1825), Onychogomphus forcipatus (Linnaeus, 1758), Ophiogomphus cecilia (Fourcroy, 1785), Somatochlora metallica (van der Linden, 1825), Calopteryx splendens (Harris, 1782), Platycnemis pennipes (Pallas, 1771), and Sympecma fusca (van der Linden, 1820)]. We compared the species composition of dragonflies in the three habitats. In the case of larvae in the main channel G. vulgatissimus (48.0%), C. splendens (29.6%) and O. forcipatus (20.8%) dominated, while in the dead channels C. splendens (49.5%) and P. pennipes (23.7%) were found most frequently. In the side channels G. vulgatissimus, O. forcipatus and C. splendens were the most frequent species. S. flavipes appeared only in the main and side channels, while S. metallica and S. fusca were only detected in the dead channels.