Thread subject: Diptera.info :: Dysmachus trigonus?

Posted by Paul Beuk on 11-06-2007 22:10
#1

Checking before I put them in the gallery.
About 10 days ago (3 June) I stumbled upon these two flies in copule. Even though the tempreature was running towards the 30's I could come very close (my camera is not that much state of the art) and shoot a few shot. The sun prevented me to see if any was really any good, but i am quite satisfied. Size about 12-13 mm (each), on bare, sandy soils.

Posted by Paul Beuk on 11-06-2007 22:11
#2

Close up.

Posted by Paul Beuk on 01-07-2007 17:07
#3

No one?

Posted by Cor Zonneveld on 01-07-2007 21:35
#4

Yours look not quite so bristly as mine, which Mark van Veen IDed as trigonus.

Posted by Paul Beuk on 11-10-2007 07:51
#5

Danny? Can you tell more?

Posted by conopid on 11-10-2007 13:59
#6

Paul,
i find that the best feature to determine Dysmachus trigonus is the "fans" of long hairs at the margins of the tergites. These show up best when viewed dorsally. I cannot make these out in your photos, but the angle is not good for viewing this feature. Did you get any dorsal shots?

Posted by Danny Wolff on 11-10-2007 19:29
#7

Hello Paul,

yes, I think it is Dysmachus trigonus. Other Dutch species with (nearly) completely black legs would not fit other characters seen in your image. Do you have a detail of the genitalia? Shape of the ovipositor is very characteristic in trigonus.

Greetings, Danny

Posted by conopid on 12-10-2007 08:44
#8

Paul,
I agree with Danny. On closer inspection of the third photo, you can easily see some of the fans of hairs sticking out above the abdomen - on the opposite side of the abdomen from the camera.

Edited by conopid on 12-10-2007 08:47

Posted by Paul Beuk on 12-10-2007 08:54
#9

I have to dig up the original images.

Posted by John Smit on 12-10-2007 10:25
#10

The easiest characters for ID-ing this species in the Netherlands is the combination of black legs and the bristles on the thorax, going all the way to the head, in stead of being restricted to the posterior part.

John