We investigated the odonates of Wadi Cherf, a tributary of Wadi Seybouse, and explored the main environmental factors that may be important drivers of the abundance and diversity of Odonata assemblages. PCA analyses demonstrated a significant altitudinal gradient associated with water flow, temperature, vegetation cover, substrate and adjacent land use. Notably, pollution was a dominant…
Mitigation measures carried out at the regulated metarhithron Gurtenbach in Upper Austria were evaluated by a survey of the dragonfly fauna. The assessment method developed in this study was based on the longitudinal distribution of dragonflies along riverine biocoenotic regions (the “Rhithron-Potamon-Concept” explains changes in species composition along a river’s length). Numerically expressed habitat preferences…
In a field study carried out in 2011 and 2014 adult dragonflies were identified as a rapid and easy-to-use means of assessing habitat quality and biological integrity of Mediterranean streams and rivers in the province of Barcelona (Region Catalonia, Iberian Peninsula). The study included sampling sites from five different river catchments: Besòs, Foix, Llobregat, Ter…
Several odonate species are threatened in the Mediterranean basin and some of them show alarming decreasing trends. The distribution and population estimations provided by the IUCN are based on occasional field sampling or non-rigorous methodologies and could be erroneous and misleading. To obtain reliable estimations of the population size and distribution of three threatened species,…
By means of slow-motion film analysis we found new female refusal behaviour patterns against male harassment in a variety of Odonata species. Often, females could escape simply by flying faster than males. Due to the morphological preconditions, there were differences in the two suborders. In Anisoptera, several behavioural specialities were analysed: (a) females of Aeshna…
Slow motion films of fight behaviour of five different species of Odonata were analysed. In all cases biting played a major role. The biting duration depended on the duration of a stable connection between the two opponents. Sitting odonates showed much longer biting than those that were flying. In fights of Anax junius and Calopteryx…
The odonate fauna of Tuva in Siberia, Russia, is documented, based mainly on data from expeditions in 1990, 2000 and 2004, and examination of collections preserved in Novosibirsk. The checklist of Tuvinian Odonata presently includes 47 species. In the southern Ubsu-Nur depression 29 species were recorded (two just there); in the Central Tuvinian depression 34…
The biting midge Forcipomyia (Pterobosca) paludis is the only ceratopogonid species known to parasitise Odonata imagines in Europe. In this study, based mainly on the analysis of about 200 photographically documented cases, data on host species, parasite load and undisturbed position on the odonate body were analysed. The list of hitherto known hosts is extended…
Extensive surveys for odonates were completed in protected areas throughout Guangdong Province, south China during the period 1997-2005. Previously unreported data from these surveys is presented here and, together with published data, is used to catalogue the zygopteran fauna of Guangdong. Checklists are provided for the Zygoptera of Guangdong, Macau and Hong Kong. Sinosticta debra…
Of the 86 Odonata species so far recorded for the Levant, four are considered as endangered (Calopteryx hyalina, C. syriaca, Ceriagrion georgifreyi, Pseudagrion torridum hulae), six as vulnerable (Coenagrion vanbrinckae, P. sublacteum mortoni, Gomphus kinzelbacbi, Onychogomphus macrodon, Brachythemis fuscopalliata, Crocotbemis sanguinolenta), and two as extinct (Rhyothemis semihyalina syriaca, Urothemis edwardsi hulae). The history of odonatological…