Brachyopa weekend

[Roger K.A. Morris]

Stuart and I went to two woods just south of Peterborough today. I took several Brachyopa - larvae from a sap run in horse chestnut that will doubtless be B. insensilis. In Archers Wood I saw at least two Brachyopa flying around oak trunks and another around Ash - I caught the latter and thought at the time that it was a bit bigger than normal - it proved to be B. bicolor. We then went on to Brampton Wood and noted Brachyopa at a stack of aspen logs. At the time I thought this might be B. pilosa - which it was.

A good day, but quite fascinating because I would have expected B. scutellaris. The only other records of note were a female Cheilosia griseiventris and a male Heringia heringi.

Look out for trunks in sunlit locations.

Regards all

Roger

[conopid]

Hi Roger,
I have never seen Brachyopa in Shropshire in twenty years of looking! Even though I religiously look for flies on sunlit trunks when in old woodlands. Mind you I rarely see sap runs. Interestingly I regularly see Ferdinadea cuprea on tree trunks.

I visited a small wet woodland yesterday and found Heringia pubescens, Cheilosia antiqua, Neoascia podagrica and N tenur and a fleeting glimpse of a red tailed Criorhina ranunculi. Interestingly, though masses of Epistrophe eligans have been out around Shrewsbury, this wood, some twenty miles north, had not a single E eligans flying.

At Attingham Park, Shrewsbury, there has been an immense emergence of Melanostoma scalare and Platycheirus albimanus taking place all week, towards the end of the week huge numbers of Syrphus vitripennis joined the show. The season is certainly well under way now.

[Roger K.A. Morris]

Hi Nigel

I'll bet the Brachyopa are there - I think there is a bit of fieldcraft involved - maybe I'd better run a brachyopa course!

Don't look for sap runs just take a careful look at sunlit parts of oak/ash and poplar trunks between 18 inch and 3 ft above the ground.

I'm sure they are there - I found lots in a poplar plantation near Ludlow.

Regards

Roger

[conopid]

Hi Roger,
I bet they are there too. I just can't find them. I have a feeling that I have been looking too high up the tree. I don't think I concentrate much on the bits of trunk at the 18 inch level, so maybe that's where I have gone wrong. Will try again this season, with my eyes aiming lower!

[chris webster]

I can't find them either Nigel. Well, I've seen a few on Beech trunks in recent years, but nothing there today. I checked every sunlit tree I could find today, at the appropriate level, but only came up with F. cuprea. Plus innumerable snails.
Sap runs are hard to find too, though I've noticed that Red Admirals can locate them on Oaks.
Portevinia maculata were flying today near Reading, in their usual patch of Ransoms. There's plenty of that plant in the wood, but the colony sticks to the same small area for some reason.
My front garden consists of an Elder tree and masses of Blackfly. Proving very popular with aphidophagous types as usual, though the neighbours don't like it much.

Chris.

[Roger K.A. Morris]

Hello Chris

The thing to look for on beach is big fallen trunks with the bark still well attached - the brachyopa can be found running over the bark. Do please hold on to material - they are tricky and species on beech can be very interesting.

I have found them round very small sap runs on beech but also just flying round beech trees. The best I found was a run of felled beech with sap exuding - there were a great many (B. pilosa)!

Regards

Roger

[conopid]

The value of an on-line master class from Roger cannot be underestimated! I spent an hour around woodland at Attingham Park, Shrewsbury today, following Roger's advice and found two Brachyopas, thus breaking my twenty year duck!

Best of all one of them looks to be B bicolor. I took this one resting on an oak trunk at 2 metres height. The second, a B scutellaris was flying about the base of a Sycamore. Both trees were in sunlight. Both are males. I am well chuffed.

I'll get the B bicolor to Roger for checking in due course.

[Roger K.A. Morris]

Excellent Nigel

Sounds like a weekend masterclass would be a great benefit to others - perhaps next year we should do this.

Important point is holding on to specimens - the only way of sorting B. bicolor!

Look forward to LOTS of Brachyopa

Regards

Roger

[conopid]

And today, on an evening stroll around Attingham park, although I did not turn up any further Brachyopa, I found two Xylophagus ater on tree trunks.

[John O'Sullivan]

I had to wait for this weekend for my Brachyopa, and it was a pleasure to find about ten B.pilosa at Marston Thrift, Beds., on 10th May. All were hovering by, or sitting on, stumps of pines, evidently cut some time ago. I caught five, and all were males, as were two others that I saw well: I doubt that there was a female among the ten. Present in the same clearing was a fine female Cheilosia albipila, and there were plenty of other species present in the wood. All in glorious weather, too.

Happy hunting.

John

[Roger K.A. Morris]

That is a fascinating record John - I think you need to get the specimens looked at - they could be a bit interesting as I've never come across Brachyopa at pine - might just be NTB and at the very least a VERY interesting association record so worth a note in Dipterists Digest.

Regards

Roger

[chris webster]

Continuing the Brachyopa hunt, I examined approx 100 mature beech trees in a wood north of Reading today [Sunday], finding only one with a significant sap run. This tree was the focus of activity though, with a female Criorhina ranunculi and male C. floccosa examining the rot holes at the base, though not the sap run.
There was one male Brachyopa hovering close to the sap run, which was on the shady side of the trunk, in comparative gloom. I could see no sensory pit on antennal segment 3, and the front quarter of the scutellum was dusted, without central groove. So I take this to be B. insensilis, though there are no horse chestnuts in that wood. The hind femora were slender, especially when compared with photos of B. bicolor. Is this a good diagnostic feature?
Roger will despair of me, but I didn't retain the specimen. My reward for that was that I immediately found my first ever Brachypalpoides lentus, a male loudly buzzing around the base of another beech.

Chris.

[Roger K.A. Morris]

Correct Chris

I utterly despair!!!!

Why oh why can people not hold onto specimens - when I and a few others are gone there will be a complete lack of reliable data on species' distributions and few capable of rectifying the problem! That is only twenty years hence so get your thinking caps on - especially those with paid jobs pontificating about "biodiversity action plans" (sorry not a personal dig but a generalised point).

If you look at the data we now have 275 species and people that give dubious ID to everything and cannot back their records up - biodiversity is utterly buggered - we might just as well pack up and go home - god knows why I spenk £5k pa from my personal income trying to make sure that national coverage is effective - I might just as well go to South America for a couple of trips and do something that will be valued because quite frankly the UK is slipping from its premiere position to that of a nonentity also-ran!

Don't think this is preserving biodiversity - it will destroy it because no-one will know what they are looking at with any certainty - we are letting down the past generations - Darwin, Wallace, Huxley and many more. In many ways this is playing into the game of those non-believers such as Buckland.

Roger

[conopid]

Count to ten Roger…..

Although there are plenty of people unwilling (it seems) to take specimens, there are still plenty who are. However I share your concern that the next generation of entomologists are showing a worrying tendency of avoiding taking specimens. This practice, or non-practice, seems to be based on a misplaced concern that specimen-taking will damage populations of rare species, or worse still out of some silly romantic notion of never killing anything unnecessarily (how many of the people who refuse to kill the odd fly, will happily drive everywhere in their car, indiscriminately slaughtering untold numbers of insects and other beasts?).

Maybe we should start meeting this problem head on. What might be needed is a really concerted effort by the recording community to get universities, conservation charities, etc to emphasise the chronic need to develop a new generation of competent entomologists, who understand the need for reliable data and the need to collect and curate specimens. Perhaps the Dipterists Forum could join forces with BWARS and others to promote the cause, with some well targeted literature – particularly aimed at all the environmental management/biodiversity management graduate studies at universities, where many of the next generation are being trained.

If it’s any consolation I have certainly retained my Brachyopa specimens and I always retain any specimen that cannot be identified for certain in the field. The down side of this is that I have far too many boxes of dead flies, some of which I must pass on to a museum at some point.

[Roger K.A. Morris]

Hi Nigel - points well made.

I know the feeling about specimens and boxes - I used 6,000 continental length pins last year and am now buying pins at a rate of 10,000 a time (£230 just for these plus another £150 for the A1s)! God knows what the storebox real-estate is.

I'd be more than happy to do something to address the issue - but as you know we already run several courses each year when we religeously emphasise the need for collection. I fear that the only way is to take a robust approach to records and then not get any!

Keep up the good work - lots of interesting stuff at the DF field meeting last weekend ibncluding I think a good haul of Cheilosia pubera - which cannot be done by jizz.

Regards

Roger