Posted by Eugene K on 18-07-2020 20:26
#1
2020_07_06 Russia, Novgorod district.
Please, help id.
Edited by Eugene K on 18-07-2020 20:29
Posted by Sundew on 19-07-2020 02:00
#2
There are three similar
Chalcosyrphus species in your region:
C. femoratus,
C. valgus, and
C. rufipes. In a Swedish paper (
https://docplayer...hidae.html) a key is given, which I just translated. - I would exclude
C. femoratus that I saw some years ago (see
https://diptera.i...d_id=48510, because your fly does not have yellow haltere knobs.
C. femoratus males have long hairs on tibiae 1 and 2, but your fly is a female, so this character is not helpful.
C. valgus and
C. rufipes can be told apart by the colour of the short, spiny bristles on the underside of the middle tarsus. In
C. rufipes these bristles are black, whereas
C. valgus has yellow bristles. Unfortunately, this character is not visible in your picture, so we are stuck with "
Chalcosyrphus spec.", sorry!
Regards, Sundew
Posted by Philippe moniotte on 11-02-2021 18:47
#4
Arista entirely reddish points to valgus, it seems.