Thread subject: Diptera.info :: ID Thereva

Posted by Patrick Le Mao on 25-11-2013 20:27
#1

Hello

This Thereva was photographed in a little swamp on a sand dune near Saint-Brieuc (Brittany) on August 27th, 2013.

It could be Thereva nobilitata, but I am not really sure of my identification...

can you help me?

Patrick

Posted by Patrick Le Mao on 25-11-2013 20:27
#2

another picture

Posted by Ectemnius on 27-11-2013 09:59
#3

Hello Patrick,

Your ID is correct. Although this is a atypical specimen. The marking on the frons is not shaped like an old rayban pilot sun glass. Also its straight and touches the eyes over a considerable distance. That could point in the direction of T. valida. But that species has less dusting on the front of the abdominal tergites and has a more greyish habitus.
Still, identification of Thereva off a photo is usually very difficult.

Greetings,

Ectenius

Posted by libor on 27-11-2013 10:32
#4

Ectemnius, my first impression from the picture was absolutely the same as yours: strange nobilitata. Remark to your last sentence: identification of Thereva under microscope is also difficult ;-)

Posted by Ectemnius on 27-11-2013 11:22
#5

Hah! You are absolutely right libor! :)

Posted by Patrick Le Mao on 27-11-2013 17:31
#6

Thank you very much...:D

I know that Thereva is very difficult to identify, so I'm very pleased with your answers