Sunday 19 January 2020

Wednesday 8 January 2020

Tuesday 11 June 2019

Sawfly mines in elms

Today was too rainy to find adult sawflies, but I did take a look at some leaf-mines in local elms in S Norfolk. I've been interested in these for a while, given that some sources say one species is involved - Kaliofenusa (was Fenusa) ulmi, whilst others list two species - K. ulmi and K altenhoferi.

The apparent differences between these two species are (per Liston 1994, Br.J.Ent.Nat.Hist. 7, 15-18):

a) differences in fine detail of the structure of the head, and the terminal antennal segments, of the adult - no good unless I manage to rear some out (v hard with sawflies) or find the adults in flight (v hard with Tribe Fenusini in my experience so far).

b) species of elm, with K. altenhoferi found on Ulmus minor, U procera and possibly hybrid elms; whilst K. ulmi is on Ulmus glabra. OK, but there has been a lot of discussion recently about speciation in elms, with potentially over 60 British species. Perhaps elm specialists can tell me if what was previously called U. glabra (Wych Elm) is sufficiently different to all the others??

c) position of mine, with K. altenhoferi mines apparently starting mostly in leaf-margins, vs. K. ulmi mines starting mostly in the leaf-blade interior (and "even completed mines often do not touch the leaf edge"). There are rather a lot of "mostly" and "often" here, and Liston also notes that parasitoids may cause mines to cease earlier than might otherwise be the case.

I took the following photos today - 11th June 2019. The majority were in small-leaved hedgerows elm suckers in Shotesham at ca TM24829975. The last two images are of a mine from a larger-leaved elm - perhaps a Wych Elm? - in Poringland at about TG26260349.

One could arguably make a case for both species here, but I'm not sure I'm buying it. Many of these mines (apart from the last) were from the same cluster of trees and were surely relating to the same species. Opinions very welcome.

Note - I believe that the form of the mine, larvae and frass rules out other potential leaf-mining species, but please do say if you think they might be something else.

Given the two clusters of frass, I wonder if this might be two mines that have run into one? 


Not reaching the middle so altenohoferi?





Not quite reaching the edge so ulmi?
Not reaching the middle so altenhoferi?

Larger leaf from Poringland, mine nowhere near the middle - so altenhoferi (but if Wych Elm should be ulmi?)

close-up of previous




Monday 28 May 2018

Sawfly adventures in May (most of, and a bit of April)

My blog remains somewhat sporadic, but this is partly for the good reason that it's because I've been finding lots of sawflies. I'm finding the process of catching, labelling, curating, pinning, identifying somewhat heavy going, but am persevering in the hope it gets easier in due course. Anyway, I haven't left myself much time for blogging, but here's a quick update since last time. I'm including things I've currently identified, although there's lots more (well about 50 more specimens) I've still not sorted out yet.

Sun 29th Apr - found Macrophya alboannulata in the garden (Shotesham), under an elder (the foodplant). Wasn't aware of this "new" (i.e. 1980s!) split, so good to learn about it.

Tues 1st May - Dolerus nigratus netted in Thetford.

Fri 4th May - caught Dolerus nigratus by hand early morning in Shotesham. Later at the Nunnery Lakes in Thetford, found 7 sawflies but to date have only identified Athalia cordata successfully (most of the others are Nematinae which I'm leaving til later in the year).

Sat 5th May - in Shotesham, found Macrophya alboannulata, Dolerus niger, D. nigratus and D. triplicatus. Also went for a hunt around Ashwellthorpe Wood and found 11 sawflies, including Athalia cordata, Nematus lucidus, Claremontia alternipes, Eutomostethus ephippium and Pachyprotasis rapae.

Sun 6th May - in the garden, the rolled rose leaves of Blennocampa phyllocolpa were beginning to be in evidence, and closer inspection lots of the tiny adults were visible around the roses.

Mon 7th May - bank holiday, so we went for an early morning trip to the beach at Covehithe (Suffolk, I know, sorry). I was pleased to find Pamphilius hortorum here, as well as the tiny Hoplocampa chrysorrhoea.

Tue 8th May - back in Thetford, I was surprised to net Strongylogaster multifasciata by the river in an area apparently devoid of ferns, which this species is normally found on.

Wed 9th May - a lunchtime walk at Thetford Nunnery produced Athalia cordata, A. lugens, Dineura stilata and several Hoplocampa crataegi (small sawflies beaten from hawthorn blossom)

Thu 10th May - went over to Shropshire to attend the annual conference of the NFBR (National Forum for Biological Recording). In the evening, we found Dolerus sanguinicollis in the grounds of the FSC's Preston Montford headquarters.

Fri 11th May - still at Preston Montford in Shropshire, in the evening I was shown my first Iris Sawfly Rhadinoceraea micans by Ian Wallace (national caddisfly expert), plus also noted Aglaostigma fulvipes.

Sat 12th May - a small group of us from the conference went on a field trip to Brown Moss in Shropshire. I found several sawflies, and Ryan Clark kindly netted me several more. To date I've identified Dolerus madidus, D asper, Tenthredo colon, Rhogogaster viridis, Birka cinereipes and Apothymus serotinus (the latter as a larva, which I appear to have failed to rear successfully - feeding it the wrong oak perhaps?)

Sun 13th May - back in Norfolk again, lots of Blennocampa phyllocolpa still in the garden, and I found Dolerus picipes elsewhere in the village.

Tue 15th May - at Thetford Nunnery Lakes, my first Eriocampa ovata of the year, plus Dolerus nigratus and D sanguinicollis.

Fri 18th May - a lunchtime walk to the Nunnery Lakes produced the impressive Macrophya annulata plus Hoplocampa crataegi still.

Sat 19th May - spent the day around Shotesham, finding Arge nigripes, Dolerus niger, Aglaostigma fulvipes, Empria alector (I think, would be a new species for Norfolk too), Dolerus vestigialis, Blennocampa phyllocolpa and Macrophya alboannulata.

Sun 20th May - again around Shotesham all day, noting Dolerus nigratus, Ametastegia tenera, Aglaostigma fulvipes and Pontania proxima, the latter in the form of the first galls in leaves of White Willow.

Mon 21st May - lunchtime in Thetford produced Aglaostigma fulvipes, Aglaostigma aucupariae, Pontania proxima (galls) and Dolerus sanguinicollis.

Wed 23rd May- lunchtime in Thetford produced Calameuta pallipes and Athalia lugens.

Thu 24th May - another lunchtime walk to the Nunnery Lakes and I found Tenthredo mesomela and several Athalia circularis; the latter I'm confused about because they're around a patch of Skullcap where I found Athalia scutellariae last year, but these are definitely not that species.

Fri 25th May - again in Thetford, noted a fine Tenthredopsis litterata plus Birka cinereipes and Blennocampa phyllcolpa.

And that takes me up to this weekend, when I've found plenty more around Shotesham and at Surlingham Church Marsh, but mostly not yet identified yet. So that'll do for now.









Wednesday 25 April 2018

April sawfly hunting

Spring was a long time coming this year, being cold well into April. I'd had reports of sawflies early in the month from James Emerson, James Symonds and Neil Marks but I didn't get off the ground until 14th April (when Tim Hodge also reported his first, with Nick Elsey the next day). From here on I had quite a good run to 22nd April, then it went cold again. My finds were as follows:

Sat 14th April: Shotesham Common, by sweeping Juncus I found Dolerus varispinus and Pachynematus lichtwardti (I believe).

Tue 17th April: I found four sawflies at Thetford Nunnery Lakes, one netted from a grassy glade (recognised and later confirmed as my first Nematus lucidus), two from sweeping around willow blossom (both Nematinae) and Hoplocampa fulvicornis was swept from blackthorn blossom.

Wed 18th April: afternoon walk on Shotesham Common where I swept three Dolerus spp and one Cladius compressicornis.

Thu 19th April: I popped out to Two Mile Bottom in Thetford Forest at lunchtime, with the express aim of trying to find Xyela julii, and amazingly was successful, sweeping just one from pollen-heavy birch near pines. I also swept two Dolerus, apparently from pine and birch oddly.

Fri 20th April: I swept one Nematinae on Shotesham Common.

Sat 21st April: I visited Lynford Lake in the Brecks and swept four Nematinae and one Hoplocampa chrysorrhoea. I then moved to Foulden Common, finding Nematus lucidus, Hoplocampa fulvicornis and my first ever Pamphilid, this being Pamphilius sylvaticus; also another Nematid and a Dolerus.

Sun 22nd April: Around Shotesham I found Nematus lucidus, another Nematid and a confusing sawfly which seems to key to Hoplocampa but then doesn't seem to fit. Will come back to this.

Then cold on 23rd-25th. Will report on more finds and any further identification successes next time.

P.S. Other species recorded by other recorders so far this year in Norfolk have included Dolerus gonager, Aglaostigma aucupariae and a great record of Acantholyda erythrocephala.

P.P.S. I'm generally not a great blogger, but will try to keep this going reasonably regularly, without promising any nicely polished or well-illustrated articles.