Diptera.info

Posted by Thoma2008 on 08-07-2023 07:43

Hello,

(Body-)Length about 2.2 mm

Found at the edge of mixed beech forrest. 7th July 2023
Konstanz, Germany, Lake Constance area, Position 47.692528 N, 9.177509E
480 m above sea level.

Peplomyza sp.? Peplomyza litura or Peplomyza discoidea?

Thank you,
Thomas

Edited by Thoma2008 on 30-07-2023 08:38

Posted by Thoma2008 on 30-07-2023 08:38

I found following criterion

"As can be seen from the accompanying photographs, Peplomyza litura is quite easily identified by the rather smoky-brown wings that are almost black in their rear half. The thorax is also streaked and the eyes are a rather vivid red. All the legs are entirely pale-coloured – there is one other British species of Peplomyza, P. discoidea, which looks very similar to P. litura except that all the legs are partly dark-coloured."
https://stories.rbge.org.uk/archives/23236

This is in line with the photos from P. discoidea presented at https://www.gbif.org/occurrence/gallery?taxon_key=1569881 and the photos for Peplomyza litura https://www.gbif.org/occurrence/gallery?taxon_key=1569883

Furtheremore the dark colouration in Peplomyza litura is less present in the frontal lower part of the wings when compared to P. discoidea.

=> Peplomyza litura.

Please feel free to disagree with me! I am just learning....

Thomas

Edited by Thoma2008 on 30-07-2023 08:39

Posted by Thoma2008 on 30-07-2023 09:19

Dear Jürgen,

Thank you for your kind reply.

Good argument! Honestly, I was not aware that this species is also present in this area.... That makes it more complicated!

Do you know of any critera to distinguish both species based on photos? I may then look on other photos I took if I can find those criteria.

I do not know if the following is a strong or non-relevant criterion for the distinction of Peplomyza intermedia and Peplomyza litura (=> please disagree). Based on the photos I have seen from Peplomyza intermedia, there are just two but broad dark bands on the back whereas P. litura has four smaller ones. For example:
https://www.biodiversity4all.org/taxa/1087570-Peplomyza-intermedia
https://www.kozanek.com/en/insects/3289/59/3232/
https://www.izeltlabuak.hu/faj/peplomyza-intermedia

If (!) this should be a strong criterion, I would still end up with Peplomyza litura.

Best regards,
Thomas

Posted by Juergen Peters on 30-07-2023 16:21

Hello Thomas,

sorry, but I can't tell you anything more. I'm no expert, I only read of Peplomyza intermedia, with made all my own Peplomyza "identifications" rather worthless... :|