An interesting gleaning behaviour by Lestes virens (Charp.) (Zygoptera: Lestidae)

On 1 September 19971 visited the locality Dobra-Kamenec near the town of Frydek-Mfstek (E Czech Republic), alt. 315 m. On the Riss terrace above the River, there is a pond (15x20 m) where, in a sun-lit Juncus vegetation was a web of an unidentified spider. It was approximately rectangular in shape (12x10 cm), some 20 cm above the water, supported by Juncus blades. A male L. virens was perched on a blade, some 15 cm from the web, oriented vertically, heading down the web. The web was sun-lit, and from the dragonfly position all fibres could be seen very clearly. In its centre was caught a small leafhopper (Homoptera). Suddenly the dragonfly took off, flew towards the web, and approached the leafhopper. During several seconds it touched the web 6 times with stretched legs. Finally the dragonfly managed to get the leafhopper out of the web and flew to the nearby Juncus blade, where it started to consume the catch. The spider, still sitting on the blade to which the web was fixed, did not seem to have noticed the loss of the prey.