News
A Blepharipa sighted in Sussex
The diptera.info forum has been very active with tachinid sughtings this year. One photo in particular from Gordon Jar caught my eye - a Blepharipa sp. caught in his back garden in Sussex. The debate went on for a few days as to which one it might be - schineri or pratensis - the former being rarer in Europe but already on the UK list - the latter being common in Europe but only known as close as Guernsey.
Unfortunately Gordon hadn't collected the specimen so we only had the photos to go on - ironically taken while it was sitting in a collecting pot and on his hand! The concensus at the time suggested it might be pratensis, which would have been a new species for mainland UK but without a specimen to back it up we wouldn't have been able to add it!
In the end I had a brainwave, while watching a particularly boring World Cup match on TV, and I emailed some photos to Peter Tschorsnig in Stuttgart. He is quite sure that (accepting the limitations of determining flies by photo) it is schineri, which is rather a relief for us because it is already on our list (albeit a very rare species) and that means we can accept the record into the scheme database - horray!!!
Phytomyptera minutissima - new to the UK list
Ivan Perry lent me some 'difficult' specimens at the 2005 BENHS exhibition to have a look at. One in particular was interesting because he had run it through the Central European key (available on the downloads page) and it came out to Elfia (Phytomyptera) minutissima.
Sure enough, it keyed perfectly so I thought I'd try 'digi-scoping' to take a digital photo through the microscope and then send this to Peter Tschorsnig for his comments. This method doesn't always work of course but this time we were lucky because the sinuous vein M proved to be very characteristic and Peter was able to confirm it was P.minutissima (Elfia in the Central European key has been merged with Phytomyptera).
Anyway, well done Ivan - I still don't know how he manages to see so many marvellous flies each year! Watch for a paper in Dipterists Digest officially adding it to the UK list.
Watch out for Tachina magnicornis & Gymnosoma nudifrons
A few years ago I chatted recently to Theo Zeegers in Holland and he suggested that Tachina magnicornis might be worth looking out for in England. In Holland it occurs rarely on sandy heath in similar habitats to Gonia picea so he suggested it might be in locations such as Kent or the New Forest in August.
He also mentioned that sightings for Gymnosoma rotundatum should be checked against the Central European key because this is a difficult group to identify and nudifrons is actually commoner in Holland than rotundatum.
Of course it doesn't mean they are here yet but we have found new species every year and with global warming anything is possible.
Carcelia laxifrons - new to the UK list
After chatting to Peter Tschorsnig about the Carcelia revision (see below) he suggested we try getting in tough with 2 authors of a 1897 paper which said they had reared Brown-tail moth from Carcelia lucorum. Peter said this would be an unusual host of that species - but an ideal host for C.laxifrons.
We did some detective work and thankfully the authors still had the specimens and lo-and-behold, they turned out to be Carcelia laxifrons!
Watch Dipterists Digest in 2006 for the paper adding it to the list and the reworked Carcelia key..
Reworking of the key to UK Carcelia spp.
In response to a recent addition to the British list (Collins,
Gibbs & Raper 2002), we have decided that a revision of the
key to British Carcelia spp. is required. Carcelia
are an enigma - a couple of species (lucorum and tibialis)
are relatively common while the others (atricosta, bombylans,
gnava, puerula and rasa) are exceptionally
rare. In fact they are some of the rarest of the British Diptera
with no more than 10 records per species.
One of the problems with this group has been that the standard
British key (Belshaw 1993) covers only about half the European species.
With so many of this genus being very rare and potentially existing
in very low numbers it is thought that there could be specimens
in collections that have been either misidentified as one of the
species in the old key - or left as ’indet’.
With this in mind we have had all our own personal specimens of
the rasa/puberula group confirmed by Hans-Peter Tschorsnig
(Stuttgart Museum), the Euopean tachinid expert. His work confirmed
most IDs but turned up some more bombylans amonst the catch.
Our next step will be to look through the larger British collections
(Natural History Museum and Oxford University Museum) and use our
specimens as a reference collection to aid our IDs.
The result of this work will be a new key to the British Carcelia
spp.
Tachinids to look out for this summer:
Sturmia bella, a very recent addition to the UK list (see
New Tachinids page) but has been surfacing
in quite a few surveys in 2000 and 2001. This fly has colonised
rapidly and is likely to occur anywhere in Southern England - its
hosts appear to be the larvae of species of medium to large butterfly
of the orders Nymphalidae & Satyridae. Any fly that keys through
Belshaw to couplet 171, but does not then feel comfortable as either
of the choices in coulet 172, and is ~10mm in body length with faint
orange marks on the antereo-ventral side of the abdomen and a conspicuous
’comb’ of hairs along the hind tibia may be Sturmia bella.
Last year the first Sturmia bella appeared in my samples
on 19.viii.2001.
Ectophasia crassipennis is a common tachinid throughout
Europe but has never been recorded on the British mainland. However,
it began to colonise the Channel Islands in 1996 and has become
more and more common each year (Charles David, pers. com.).
For this reason I feel it is only a matter of time before we get
the first records along the south coast. It’s closest relative here
in the UK is Phasia hemiptera, but it differs from this species
in having more orange on the abdomen (hemiptera is mainly
brown) and having a spotted, lightly-shaded wing (hemiptera
has a uniform, dark-shaded wing).
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