Posted by Andre Megroz on 25-10-2016 17:17
#1
Switzerland, St. Gallen (650 m), 18/10/2014.
Thank you
André
Edited by Andre Megroz on 06-11-2016 21:10
Posted by Juergen Peters on 25-10-2016 19:35
#2
Hello André,
to attract the attention of the Syrphidae specialists you should post this in the Syrphidae subforum.
It has no dark borders around the tergites, so I suspect (as a non-expert), that it is not the usual
R. campestris.
Posted by Sundew on 26-10-2016 22:27
#3
There are 3 species:
R. borealis, R. campestris, R. rostrata. A female
R. borealis can be ruled out because the arista bears no long hairs, the snout is not short and strongly curved, and the tibia 3 has no black tip. (The male would look different, having a black thorax and scutellum, but your picture shows a female.)
As Juergen pointed out, a typical
R. campestris has a dark abdomen edge, because (beside the hind margins) the
side margins of the tergites are darkened. Legs, face, and scutellum are duller and darker in colour than in the third species
R. rostrata. In the latter species, the abdomen edge is not darkened, the thorax is somewhat more bluish, and face, legs, and scutellum are orange-yellow rather than dull brown. Therefore I would call your fly
R. rostrata. The only uncertainty is that the snout seems rather long and straight (like in
R. campestris) instead of shorter and a bit curved downwards. However, the non-dark abdomen edge is stressed in all descriptions, so
R. rostrata should be OK.
Regards, Sundew
Edited by Sundew on 26-10-2016 22:31
Posted by Andre Megroz on 06-11-2016 21:14
#4
Thank you,Sundew, for your explanations.
André