Thread subject: Diptera.info :: Oestrus ovis

Posted by John Webley on 25-08-2006 18:44
#1

Am I right in thinking this is Oestrus ovis? Taken in Kent, UK today. About the size of a Bluebottle.
Thanks

Posted by John Webley on 25-08-2006 18:58
#2

I've changed the file name. I think that may be the problem

Posted by Zeegers on 25-08-2006 19:01
#3

John

No. This is a Muscid (probably Phaonia). Oestrus is very rare these days and has the bend in vein M, discussed in a previous recent post on Tachinidae.

Theo Zeegers

Posted by ChrisR on 25-08-2006 19:01
#4

Doesn't look like Oestrus to me - looks more like a muscid.

Posted by John Webley on 25-08-2006 19:51
#5

The fly recently identified as Phaonia is attached. The fly I've posted today was significantly bigger and wrinkled at the back. Do they vary that much

Posted by crex on 25-08-2006 21:14
#6

Please do crop photos a bit more. The flies are small as it is ... ;)

Posted by John Webley on 25-08-2006 21:48
#7

Fly taken today cropped a bit more. This fly was about Bluebottle size.

Posted by John Webley on 25-08-2006 21:50
#8

Fly taken several days ago and identified by the group as Phaonia Pallida. Smaller, about housefly size.
Hope the new images help.
John

Posted by Tony Irwin on 25-08-2006 22:00
#9

John Webley wrote: Do they vary that much?

Yes, they do. We have 46 species of Phaonia in Britain - ranging from all orange (like pallida) to some that are plain grey to ones that have a chequered abdominal pattern and striped thorax. They are all much the same shape, though!
When you do see Oestrus, you'll recognise it straight away. There are some good images at http://www.icb.us...estrus.htm, but beware of image searching with Google for it - I found a Pollenia and Hypoderma as imposters! The last time I found Oestrus in Britain was about 20 years ago on an army firing range - the sheep were worth more dead than alive, so the farmers didn't bother treating them.:(

Posted by John Webley on 25-08-2006 23:16
#10

Oh dear. Proof of the dangers of unscientific attempts at identification. I thought it looked similar to the illustration in Colyer & Hammond but now see the error of my ways.
Any thoughts on which one this is would be appreciated.
John

Posted by ChrisR on 25-08-2006 23:50
#11

I agree with the rarity and distinctiveness of Oestrus ovis. I was lucky enough to catch one in a malaise trap a few years ago in the week the local Wildlife Trust moved a flock of sheep onto the site I was monitoring (Hartslock NR, South Oxon). :D When I showed it to friends most had never seen one and even expert dipterists said they'd only seen one about 25 years ago!