Thread subject: Diptera.info :: Large hairy Syrphids: both Criorhina ranunculi? --> confirmed

Posted by Juergen Peters on 17-04-2008 21:25
#1

Hello!

Many Syprhids on the wing today here (northwest Germany), although it was only 10-12 ?C (but mostly sunny). The most spectacular rested on a tree trunk at the forest. At first glance I thought of one of the Bombus pratorum queens taking a break Wink. Length about 15 mm.

A few minutes later I saw another, smaller one with orange haired abdomen end resting on the ground (last picture below). Are both Criorhina ranunculi? Thanks!


Large picture (1600x1200, 196 KBytes):
http://www.foto-u..._M_big.jpg
Wing venation more closely:
http://www.foto-u...nation.jpg

Edited by Juergen Peters on 18-04-2008 15:14

Posted by Juergen Peters on 17-04-2008 21:26
#2

Second picture.

Posted by Juergen Peters on 17-04-2008 21:26
#3

Third pic.

Posted by Juergen Peters on 17-04-2008 21:27
#4

The individual with the orange abdomen.

Posted by Dieter on 18-04-2008 08:54
#5

Yes, both are Criorhina ranunculi. Different colour forms are common among bumble bee mimics (e.g. Merodon equestris, Volucella bombyans, etc.).

Cheers,
Dieter

Posted by Juergen Peters on 18-04-2008 15:14
#6

Dieter wrote:
Yes, both are Criorhina ranunculi. Different colour forms are common among bumble bee mimics (e.g. Merodon equestris, Volucella bombyans, etc.).


Many thanks for confirmation, Dieter! So no difference in sexes. The only other difference I could see, was the slightly less size of the orange individual. Both males? Or is the white haired one a female?

Edited by Juergen Peters on 18-04-2008 15:15

Posted by Dieter on 18-04-2008 17:46
#7

All females, check the frons. The size differences are normal intraspecific variation.

Cheers,
Dieter