Joe Botting's picture

Unidentified fly

Observed: 13th May 2013 By: Joe BottingInvertebrates expert

A medium-sized (from memory, 5-6 mm) fly resting on a dandelion. Metallic purple abdomen with unusual shape. Venation similar to Anthomyidae. Any ideas?

Species interactions

No interactions present.


dejayM's picture


I can't help Joe
I searched for Fly Triangular Abdomen (which it isn't specially!) and failed but was fascinated by this site
Do look (and play!)

Wildlife Ranger's picture


Joe Botting's picture

Thanks both... but still no answer.

Thanks for the link, Derek - not seen that before, but it's great fun!

I guess it's nothing too rare, WLR, or we wouldn't both have it at once... curiouser and curiouser. I've called in some dipterist backup, so hopefully will have a suggestion or two soon...

Neil Harvey's picture

Don't think the abdomen is purple...

I think the apparent colouration is from the wings. If you look at the tip of the abdomen beyond the wings, it is plain black.

Sorry, though, I can't help with i.d. - an Anthomyiid seems likely.


Wildlife Ranger's picture

Abdominal Colour

The ab I think was irredescent purple (on my obs) - not just the usual wing refraction I spent a while trying to get the ab without the wings I could be wrong I'll add a few more combinations


Joe Botting's picture

Mine too...

Thanks for the suggestion, Neil, but I'm pretty sure it's not right. The purple abdomen is why I photographed it in the first place. I appreciate it looks like it could be iridescence (but then, why no trace of it over the rest of the wing?), but I'm pretty certain that's not the case.

I wonder whether we'll ever get to the bottom of this one... but I'm still waiting for a response from a specialist dipterist I'm in touch with, so you never know.

Wildlife Ranger's picture

The Blues....

There you go Joe - Never find a Dipterist when you need one :-) LOL