Genus Cheilosia (Diptera, Syrphidae) with more than 300 Palaearctic species is the most speciose group of hoverflies in Europe. One of the most widespread taxa with unclear taxonomic status is Cheilosia vernalis (Fallen, 1817). This species shows great morphological variation in external morphological characters. A subdivision of the taxon has been suggested, but the male terminalia of the diff...

The diversity of hoverflies in five different habitats of the Parque Estadual de Vila Velha, Ponta Grossa, Paraná, Brazil, from September 1999 to August 2002 was studied. These five areas had been exposed to various types of anthropogenic disturbance at different times, which resulted in different stages of plant succession. In total, 2,841 specimens of 151 species of Syrphidae were collected u...

Using infochemicals to develop a push-pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion ...

Studies of insect flight have focused on aerodynamic lift, both in quasi-steady and unsteady regimes. This is partly influenced by the choice of hovering motions along a horizontal stroke plane, where aerodynamic drag makes no contribution to the vertical force. In contrast, some of the best hoverers--dragonflies and hoverflies--employ inclined stroke planes, where the drag in the down- and ups...

Measures of biodiversity change such as the Living Planet Index describe proportional change in the abundance of a typical species, which can be thought of as change in the size of a community. Here, I discuss the orthogonal concept of change in relative abundances, which I refer to as shape change. To be logically consistent, a measure of the rate of shape change should be scaling invariant (h...

Examining variations in pollinator effectiveness can enhance our understanding of how pollinators and plants interact. Pollen deposition and seed production after a single visit by a pollinator are often used to estimate pollinator effectiveness. However, seed production is not always directly related to pollen deposition because not all pollen grains that are deposited on a stigma are compatib...