Thread subject: Diptera.info :: Gymnocheta magna

Posted by Jaakko on 06-04-2010 08:15
#1

Hi,

As Gymnocheta viridis might already be in flight in Central Europe, I'll post this one as a reminder. G. magna is a bit later species, however at least in Finland the flight-times of the two overlap. Latest viridis in my collection is from July 12! The female magna specimen here is ~12 mm, so as big as the biggest viridis. The mouth edge is a good feature distinguishing the two!

Best,

Jaakko

Posted by Jaakko on 06-04-2010 08:16
#2

A close-up on the head profile.

Finland, Om: Raahe, Hakotauri, July 3, 2006. K. Varpenius leg.

Posted by Jaakko on 06-04-2010 08:17
#3

And a G. viridis female head profile for a comparison.

Posted by ChrisR on 06-04-2010 09:25
#4

Thanks - I have never seen G.magna - nice to know what it looks like :D

Posted by Zeegers on 06-04-2010 20:20
#5

Magna is in Central Europe really much later, end of May.

Very extremely rare in peat bogs.

So any Gymnochaeta on a tree stem in a forest in April will be viridis without any doubt (but this can be falsified).


Theo

Posted by Jaakko on 08-04-2010 08:00
#6

Hi,

My impression is that this magna was collected from a suburban park-like seashore (sparse trees, meadows..). I'll find out more soon.

In Finland viridis is commonly seen also on peat bogs and mires, usually in more nutritious parts of the bog with higher vegetation. In these biotopes they also occur fairly late in the season (until July) and some specimens are quite dark. I have sent examples to Christer Bergström and Joachim Ziegler but they also find these otherwise not differing from "regular" viridis. Quite irritating!

I've decided to collect all late-season Gymnochetas to be sure...