The Society for the study of flies (Diptera)
Affiliated to the British Entomological and Natural History Society (BENHS)
You are not logged in.
#1 2009-11-16 15:07:10
- Shrumpy
- Registered user
- Name: Janet Graham
- From: Merionethshire
- Registered: 2008-08-09
- Posts: 3
Polietes species
I caught this fly in a small wood by the coast in Merionethshire on 11th October 2009. It keys out in The Muscidae (Diptera) of Central Europe as Polietes meridionalis but this appears not to be a British species. Unfortunately I do not have a copy of Fonseca and I have no information on P. hirticrus. Does anyone know if my fly is P. hirticrus or if P. meridionalis has either spread to Britain or is an occasional migrant?
Janet Graham
Offline
#2 2009-11-16 19:30:40
- Howard Bentley
- Committee
- Name: Howard Bentley
- Registered: 2008-07-07
- Posts: 280
Re: Polietes species
Polietes meridionalis has recently been taken a number of times in southern England - a fact which is pending publication. I have taken it myself in two different localities in Kent this autumn. You give no indication of the size of your fly - P. meridionalis is as large as the common P. lardarius, while P. hirticrus is smaller. Your fly certainly looks like meridionalis - it appears to have a yellow anterior spiracle (that of hirticrus is dark), and the rather orange colour on the face suggests that it isn't lardarius. Check that the prosternum is hairy - in hirticrus it's bare. Of course none of this is conclusive - working from a single photograph of a Muscid will very rarely produce certainty.
Howard.
Offline
#3 2009-11-16 20:33:02
- Shrumpy
- Registered user
- Name: Janet Graham
- From: Merionethshire
- Registered: 2008-08-09
- Posts: 3
Re: Polietes species
Dear Howard,
Thank you for replying to my query.
My fly is 11mm long, which is actually larger than my specimens of lardarius. I have checked the prosternum and it has quite long hairs on the margins. The anterior spiracle is conspicuously yellow and there is definite yellow on the face.
I caught the fly in a small alder wood, immediately behind sand dunes on the coast south of Tywyn (SH 594979).
Janet
Offline
#4 2009-11-17 11:13:03
- Chrisbentley
- DF Members
- Name: Chris Bentley
- From: Rye Harbour, East Sussex
- Registered: 2008-03-11
- Posts: 37
- Website
Re: Polietes species
I have a similar specimen from East Sussex (so not a million miles away from Kent). Howard, If you're going to the muscid course in March next year is there any chance of comparing my specimen with yours?
Offline
#5 2009-11-17 18:58:54
- Howard Bentley
- Committee
- Name: Howard Bentley
- Registered: 2008-07-07
- Posts: 280
Re: Polietes species
Yes Chris, no problem. Janet, yours really does look like P. meridionalis. Any chance that we might see you on the Muscid course?
Offline
#6 2009-11-18 16:09:23
- Shrumpy
- Registered user
- Name: Janet Graham
- From: Merionethshire
- Registered: 2008-08-09
- Posts: 3
Re: Polietes species
I shall retain the specimen but I probably shan't have the oomph to attend the Muscid course. It might be interesting to collate the dates of all the P. meridionalis sightings and see if they coincide with any observed moth migration events.
Offline
#7 2009-11-30 17:43:52
- falky
- Registered user
- Name: Steven Falk
- From: Kenilworth
- Registered: 2009-11-30
- Posts: 379
Re: Polietes species
Hi Howard,
I've been waiting for this opportunity to say how excited I am that somebody else is gaining a passion for muscids. I spread myself too thinly to perhaps give the group all the time I should, but leading the workshop will be a good deed for the cause. I smiled when I saw your note in the last Bulletin. I checked my series of Polietes lardaria last week (perhaps 30-40 specimens - would be more if I had'nt assumed it was going to be more than one common species). Anyway, the majority of my females are meridionalis, and the majority of males are lardaria, but it is clear that meridionalis is widespread, and certainly not rare in Warwickshire and the Sussex downs. Be careful with the couplet in the European key - females of both species have much broader parafacialia than males (so that key character is flawed), and bristles on hind tibiae clearly vary. But yellow ant. th. spiracle and deeper golden dusting of face are pretty clear cut. Well spotted. Would you like my data for any paper? Correspond using my Warwickshire Museum E-mail (stevenfalk@warwickshire.gov.uk). Recently finished my New Forest Mire survey, and Lispocephala fuscitibia proved to be the most frequent Lispocephala of the mires and clearly associated with Marsh St Johns Wort Bog Pondweed 'soakaways'. I'll have some material to give away at the workshop.
Best wishes, Falky
Offline