Damselflies adapted to forest habitats are expected to be negatively affected by the disturbance of riparian forests, due to the change in insolation when trees are cleared. In this paper, we compare survivorship and behaviour of two populations of Heteragrion cooki by means of mark-recapture methods and focal observations of adults. We found similar densities…
Although the endemic damselfly, Platycnemis subdilatata Selys, 1849, is widespread in the Maghreb, many aspects of its reproductive behaviour, biology and ecology are still unstudied. One particular feature of this species is that its coloration pattern continues to change during maturation and afterwards, which makes it a good model for assessing age effects on behavioural…
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…
How species respond to shifting environmental conditions is a central question in ecology, especially because ecosystems are experiencing rapidly changing climatic conditions. However, predicting the responses of species interactions and community composition to changing conditions is often difficult. We examined the effects of rearing temperature and resource level on larval survival of two ecologically similar…
Oviposition in odonate females is usually considered finished when the female leaves the oviposition site. However, considering that many species lay their eggs within a set of bouts it is difficult to distinguish between the end of the oviposition bout and the end of the oviposition episode because the females can change the oviposition site…
Freshwater biodiversity is currently threatened worldwide. In North Africa, 24.4% of Odonata are regionally threatened with extinction. In this region, freshwater resources are particularly scarce and an increasing shortage of water is expected. To better understand the current threats to the endangered North African damselfly Coenagrion mercuriale we updated information on extinct and extant populations…
Second and third stadium larvae of Gomphus flavipes have dorsolateral cuticular outgrowths in the form of small basal tubercles bearing fan-shaped setae. These sensilla are aligned in two rows on each side of the thorax and abdomen. European species of Gomphus, Onychogomphus and Ophiogomphus that we examined lack these structures, having instead, at most, short…
The reproductive behaviour of the damselfly Chlorocypha cancellata (Chlorocyphidae) was filmed at 600 frames per second. Different flight styles including straight, forward flight, threat and courtship display were analysed with respect to changes in wing beat frequency and phase relationships of fore and hind wings. The analysis revealed significant differences in the flight style between…
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…
Our goal was to investigate whether the loss of riparian forests alters the structure of assemblages and populations of dragonflies and damselflies. We tested the hypothesis that the composition of the odonate assemblages found upstream from dams are significantly different from those found downstream of these barriers. To test the hypothesis, we investigated stream sectors…