David Element's Wildlife Web Page Flies 3

David Element

Wildlife Photography

and Digital Video Images

_______________________ Flies 3 - Hoverflies 3

Chrysotoxum bicinctum

Sphaerophoria scripta

Helophilus pendulus

Helophilus trivittatus

Myathropa florea

Parhelophilus sp.

Sericomyia silentis

Volucella bombylans (form bombylans)

Volucella pellucens

Xylota segnis

Xylota sylvarum

Most of the above hoverflies (apart from the Parhelophilus sp.) may be identified to species level by examining the markings closely. The bumblebee mimic Volucella bombylans exists in several different recognisable forms, each superficially resembling a different species of bee. This subterfuge is certainly convincing to the human eye, but close examination will reveal that there is only a single pair of wings, a feature typical of almost all fly species (bees have two pairs). In hoverflies a false wing margin adds authenticity to this disguise, giving the illusion of a second set of wings. The hindwings are actually reduced to small club-shaped counterbalances termed "halteres" and the absence of true hindwings is clearly no handicap when it comes to flight. Although the photographs shown are a fairly random selection, the flies are illustrated in order of classification when compared with the species list in Stubbs and Falk's excellent reference work 'British Hoverflies'.