Directed aerial displacement requires that a volant organism's airspeed exceeds ambient wind speed. For biologically relevant altitudes, wind speed increases exponentially with increased height above the ground. Thus, dispersal of most insects is influenced by atmospheric conditions. However, insects that fly close to the Earth's surface displace within the flight boundary layer where insect ai...

Dorsal ocelli are small cup-like organs containing a layer of photoreceptor ceils, the short axons of which synapse at the base of the cup with dendritic terminals of ocellar nerve fibers. The ocellar ERG of dragonflies, recorded from the surface of the receptor cell layer and from the long lateral ocellar nerve, contains four components. Component 1 is a depolarizing sensory generator potentia...

The female of Cordulegaster vanbrinkae is described and illustrated, basing on four specimens collected in Gīlān and Māzandarān Provinces, northern Iran. Their characters and variability are shown and compared with females of other Cordulegaster species.

Farming expansion has negative impacts on freshwater biodiversity. However, the effects of agricultural land use are not similar across taxa and depend local context. For instance, understudied in Neotropics (one leading regions cropland expansion). Knowledge aquatic insects from South American subtropical grasslands (Pampa) is even more incipient. We tested whether landscape modification relat...

We collected environmental and habitat data for nymphs of 12 dragonfly species (Odonata: Anisoptera) from 91 stream sites throughout eastern Texas, including urban non-urban locations. Understanding the relationship dragonflies to structure other variables is crucial purpose conserving these insects better using them as predictive tools water quality assessments, refining tolerance values. The ...

We present the concept of network traffic streams, and the ways they aggregate into flows through Internet links. We describe a method of measuring the size and lifetime of Internet streams, and use this method to characterise traffic distributions at two different sites. We find that although most streams (about 45% of them) are dragonflies, lasting less than 2 seconds, a significant number of...

Dragonfly wings resist millions of cycles of dynamic loading in their lifespan. During their operation, the wings are subjected to relatively high mechanical stresses. They further experience accidental collisions which result from the insects' daily activities, such as foraging, mating and fighting with other individuals. All these factors may lead to irreversible wing damage. Here, for the fi...

Fluorescence is emitted by diverse living organisms. The analysis and interpretation of these signals may give information about their physiological state, ways of communication among species and the presence of specific chemicals. In this manuscript we review the state of the art in the research on the fluorescence emitted by plant leaves, fruits, flowers, avians, butterflies, beetles, dragonf...