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From today, aprox 65 km NW of Stockholm, Sweden. This fly popped up when I was concentrating on another insect on this flower. Only got this mediocre shot. I think it is a Syrphid, and not a Conopid?

Edit: Changed subject (Unknown species)
Edit: Changed subject (Conops sp)

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Hello
I think, it's not a syrph, it's a species of the family Conopidae maybe Conops quadrifasciatus Degeer, 1776

Louis

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I think it is more likely to be something like Conops flavipes - it is too dark for C quadrifasciatus. However there are probably other species in Europe that it could be.

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Thanx Louis and Nigel. I've googled for photos of the Conops found in Sweden, but I have trouble seeing which one fits ...

Found in Sweden (Fauna Europaea):
Conops flavipes (Linnaeus 1758)
Conops quadrifasciatus (De Geer 1776)
Conops strigatus (Wiedemann in Meigen 1824)
Conops vesicularis (Linnaeus 1761)

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I think the black frons, silvery pleural stripes, unthickened yellow legs and large yellow theca all suggest Conops quadrifasciatus. The females are much darker than the males.

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I agree with Tony.
C. quadrifasciatus is very variable.
C. flavipes has always, surprisingly enough, strongly bicolorous hind femora: half yellow, half black.


Theo Zeegers

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Thank you very much T & T!

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Hello
What means theca ?
This word is'nt in the glossary

Thank you
Louis

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The theca is a ventral projection on the fifth abdominal segment. Together with modified seventh and eighth segments they form a clasping organ which is used to hold onto the host bee while the egg is laid. The female theca may be very large, so that it may be mistaken for a male which has smaller genitalia.
Good examples of the theca can be seen in Gerard's pictures - see http://www.dipter...hoto_id=35 and http://www.dipter...hoto_id=52.