Thread subject: Diptera.info :: Visualizing and defining costal breaks

Posted by kschnei on 12-07-2019 17:27
#1

Hi all,

I'm fairly new to keying Diptera. It's clear that costal breaks are both important and difficult to see at times. Can someone give me tips on how to best see costal breaks? I have a scope with a rather weak transmitted light at the base, do I need to get a more powerful light source underneath the specimen? And do I need to see a complete break in the vein, or just lack of pigment, or...?

Thanks!
Ken

Posted by Tony Irwin on 12-07-2019 19:47
#2

The key thing when viewing coastal breaks is to view at the correct angle. Looking at a flat wing at 90 degrees seldom works. Hold the specimen at an angle, so that you are looking obliquely towards the base of the wing. It takes some practice, so find a specimen which you know should have costal breaks, and work on that first. Good luck! :)