Squeeky trees, but, very sadly, no birds of the relatively good numbers seen up near the tops of the trees were positively identified.
There was a lovely little pond, could well be worth checking for dragonflies next year.
And there, on the South side of the pond, I hope I found a new leaf miner for me, Stigmella tityrella (Stainton, 1854), with the egg apparently always laid on the underside and amongst the hairs in the angle of a vein directly against the midrib of the Beech leaves! I should have photographed the underside of the leaves, not the topside, for a clearer view of the mine. However this error did mean that I picked up the leafhopper feeding marks as well.
The mines of S. tityrella are said to characteristically weave dramatically from side to side, but generally remain within the single leaf segment created by the midrib and two adjacent main veins. Sometimes this typical pattern can be seen but on the other hand the pictures on the web of some mines are much, much straighter than others - e.g. in Suffolk? Overall the identification certainly looks pretty good! The moth's specific list number is 0077, and a common name for the adult is the Small Beech Pigmy Moth.
However it is worth looking at the left hand leaf, and seeing how, given a very restrictively sized segment near the tip of a leaf to start off with, the mine actually crosses a main vein at the very margin of the leaf, and doubles back into a second segment, but this time heading inwards towards the midrib again. Perhaps a careless adult left this egg too close to the tip of the leaf? I wonder how often this happens.
These couple of mines were a fantastic sight, with such a clear and interesting "behavioural" separation of the two species Stigmella tityrella (seen here at Bod Petrual) and Stigmella hemargyrella (seen earlier this year at Oldbury Hill, see below), with only these two Stigmella species reported on Beech on the UK Leafminer site. These particular mines appeared to be empty of their creators (mine activity listed as June-July and August-October, with earlier flight periods of the adults), apart from the full distribution of "uncoiled" frass in the main sections of tunnel, and the narrower central line of frass in the first narrower section of tunnel. Sadly I felt I didn't have the time to search for any more mines on this site, and no other galls or mines were seen in the few dozen leaves so quickly and cursorily checked.
This species is found across UK and Europe as far as the Russian border. According to the rather limited NBN Gateway, S. tityrella has been recorded as scattered records across North Wales for example as mines in Coedydd Aber NNR, (September, 1973), Maenan (September, 1974), Maentwrog and Glan Conwy (September, 1975), Church Island, Menai Bridge (September, 1980) and as unspecified field observations in Burley Hill Quarry (Summer, 2000) and Weston Rhyn and Preston Mountford in Shropshire (July 2010). It hasn't been recorded on the NBN near Glocaenog, but this may be just lack of recording effort, or more likely, limited inputting to the Gateway.
In Norfolk or Northamptonshire (Eakringbirds), where it seems to have been actively looked for, it can apparently be found in about half the squares looked at, according to the County organisation. In East Sussex however it doesn't seem to be densely concentrated, and the County records seem to be limited to October - perhaps as mines again? The mines are said to be found in "green islands" in leaves over the autumn/winter period - so well worth looking for.
It has also been found in Kent, but there are even fewer NBN records here. There are only three listings in the whole of the county, two from the 1970s and one from 1990, with very limited details, so its something I should still keep my eyes open for in my own county!! The BBCS Kent Moth Report indicated significantly more records than this, thanks to the redoubtable David Gardiner!
Compare the blog on the 13th of September at Oldbury Hill, for the other Stigmella species that I have seen on Beech, Stigmella hemargyrella (Kollar, 1832), whose eggs are laid mainly on the upper, but on either surface of the leaf, and not against the midrib, so tends to tunnel from the margin towards the midrib. The mine often crosses at least one vein, and the frass, initially a thin central line, is said to be "coiled" from part way along the mine, although the frass trail commonly narrows again somewhat, later on in the final stages of the mine as the caterpillar approaches pupation (I wonder why?).
S. hemargyrella also initially seems to be recorded very patchily across the country with only one record on the NBN Gateway in Kent. However reference to the BBCS Kent website and its Moth Reports again indicates a wider distribution and a greater degree of abundance than listed in the NBN. Adults are also said to be easily collected on beech trunks from the beginning of May until the middle of June; the adults of the less common summer generation fly from mid-July to early August. This micro-moth is specific list number 00081, with a "common" name of the Beech Pigmy Moth, although it doesn't seem significantly smaller than S. tityrella.
S. hemargyrella has more or less the same overall phenology and European distribution as S. tityrella. From the pictures on the web I would personally say that frass patterns in both species are quite unreliable, and should not be used on their own as definitive ID. On the NBN gateway in North Wales, S. hemargyrella was found with S. tityrella in Maenan in 1974 and Burley Hill Quarry in 2000, but not in the other S. tityrella North Wales sites. I would guess from these overall indicators that S. tityrella is a little more commonly recorded than S. hemargyrella. There are no NBN records North of the Great Glen for either species although S. tityrella was logged close to Inverness itself.
Here is a rather nice overall world website for some of these leafminers, the Nepticulidae, http://nepticuloidea.info/
Fantastic, what a lucky one-off spot, another step towards completion of the Fagus sylvatica list, four of the seven possible leafminers have now been definitely spotted, in just over half a dozen visits to beech woods throughout the UK!
There was a lovely little pond, could well be worth checking for dragonflies next year.
The mines of S. tityrella are said to characteristically weave dramatically from side to side, but generally remain within the single leaf segment created by the midrib and two adjacent main veins. Sometimes this typical pattern can be seen but on the other hand the pictures on the web of some mines are much, much straighter than others - e.g. in Suffolk? Overall the identification certainly looks pretty good! The moth's specific list number is 0077, and a common name for the adult is the Small Beech Pigmy Moth.
However it is worth looking at the left hand leaf, and seeing how, given a very restrictively sized segment near the tip of a leaf to start off with, the mine actually crosses a main vein at the very margin of the leaf, and doubles back into a second segment, but this time heading inwards towards the midrib again. Perhaps a careless adult left this egg too close to the tip of the leaf? I wonder how often this happens.
These couple of mines were a fantastic sight, with such a clear and interesting "behavioural" separation of the two species Stigmella tityrella (seen here at Bod Petrual) and Stigmella hemargyrella (seen earlier this year at Oldbury Hill, see below), with only these two Stigmella species reported on Beech on the UK Leafminer site. These particular mines appeared to be empty of their creators (mine activity listed as June-July and August-October, with earlier flight periods of the adults), apart from the full distribution of "uncoiled" frass in the main sections of tunnel, and the narrower central line of frass in the first narrower section of tunnel. Sadly I felt I didn't have the time to search for any more mines on this site, and no other galls or mines were seen in the few dozen leaves so quickly and cursorily checked.
In Norfolk or Northamptonshire (Eakringbirds), where it seems to have been actively looked for, it can apparently be found in about half the squares looked at, according to the County organisation. In East Sussex however it doesn't seem to be densely concentrated, and the County records seem to be limited to October - perhaps as mines again? The mines are said to be found in "green islands" in leaves over the autumn/winter period - so well worth looking for.
It has also been found in Kent, but there are even fewer NBN records here. There are only three listings in the whole of the county, two from the 1970s and one from 1990, with very limited details, so its something I should still keep my eyes open for in my own county!! The BBCS Kent Moth Report indicated significantly more records than this, thanks to the redoubtable David Gardiner!
Compare the blog on the 13th of September at Oldbury Hill, for the other Stigmella species that I have seen on Beech, Stigmella hemargyrella (Kollar, 1832), whose eggs are laid mainly on the upper, but on either surface of the leaf, and not against the midrib, so tends to tunnel from the margin towards the midrib. The mine often crosses at least one vein, and the frass, initially a thin central line, is said to be "coiled" from part way along the mine, although the frass trail commonly narrows again somewhat, later on in the final stages of the mine as the caterpillar approaches pupation (I wonder why?).
S. hemargyrella also initially seems to be recorded very patchily across the country with only one record on the NBN Gateway in Kent. However reference to the BBCS Kent website and its Moth Reports again indicates a wider distribution and a greater degree of abundance than listed in the NBN. Adults are also said to be easily collected on beech trunks from the beginning of May until the middle of June; the adults of the less common summer generation fly from mid-July to early August. This micro-moth is specific list number 00081, with a "common" name of the Beech Pigmy Moth, although it doesn't seem significantly smaller than S. tityrella.
S. hemargyrella has more or less the same overall phenology and European distribution as S. tityrella. From the pictures on the web I would personally say that frass patterns in both species are quite unreliable, and should not be used on their own as definitive ID. On the NBN gateway in North Wales, S. hemargyrella was found with S. tityrella in Maenan in 1974 and Burley Hill Quarry in 2000, but not in the other S. tityrella North Wales sites. I would guess from these overall indicators that S. tityrella is a little more commonly recorded than S. hemargyrella. There are no NBN records North of the Great Glen for either species although S. tityrella was logged close to Inverness itself.
Here is a rather nice overall world website for some of these leafminers, the Nepticulidae, http://nepticuloidea.info/
Fantastic, what a lucky one-off spot, another step towards completion of the Fagus sylvatica list, four of the seven possible leafminers have now been definitely spotted, in just over half a dozen visits to beech woods throughout the UK!
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