Agelastica alni, by golly

Walking through the pretty woodland nature reserve of Fron Wyllt, I looked at the leaves of some Alders by a small bridge over the rapidly flowing stream.

On the first day I noticed that they had been a bit frazzled.

On the second day I actually thought about it, and wondered whether they were sawfly/slugworm larvae that might be responsible. It sort of occurred to me (very slowly) that I might not have seen this damage on Alder before. It looked a little like the shredding or skeletonisation of beetle larvae damage (as I have seen regularly on Viburmum in recent years) or slugworm damage (as I have seen in the past on Birch). Eventually I found a larva which I thought I recognised as a slugworm style of sawfly larvae. A nasty-looking glossy black caterpillar.

When I got home I saw references to Alder Sawfly, but that is white and spiky, so it was not that. By chance I came across many US references to an Alder Flea Beetle with very similar larvae and blue adults. But this apparently doesn't occur in Europe. I was now intrigued and I finally came across references and photos relating to Agelastica alni, a beetle thought to be possibly extinct, but rediscovered and apparently spreading across several parts of the UK. Oddly enough, it looks very similar to the Flea Beetle from the US.

Here is a photo of a larva on apparently fresh damage, near the base of the leaf.

And another, with slightly older damage,

Here is a photo of older damage, no larva seen.

And a photo of skeletonised leaves against the sky, indicating what potential damage could be done to the Alders along our streams and rivers.

This is the site where the worst damage was seen,

Ganoderma on Horse Chestnut by the Meanders Bridge, near Hope Farm

 A nice cross-section of the conk, hopefully the right way up:

The tree is not looking at all well, with badly cracking bark:

Alder leafmines

Phyllonorycter klemannella, (Fabricius, 1781), the Dark Alder Midget 

The first and possibly much the commonest mine I found today was Phyllonorycter klemanella (=kleemannella), the Dark Alder Midget. I was only looking on a few lower branches of an alder on the north side of the Bourne opposite Easterfield Bungalow.

These mines were both away from the midrib, and also close to the midrib. They showed no strong creases (so the mines were not Phyllonorycter rajella, larvae June and July), and it is the right time for the second generation of these larvae in the year, July- August. The mines were not long and thin enough to be confused with Phyllonorycter froelichiella, which is also un-creased, but with grey larvae, usually a bit later in the year, such as September-October. All these are underside mines on Common Alder, as opposed to Phyllonorycter stettinensis, which is strongly creased, characteristically yellow-green and on the topside of the leaf over a vein, larvae May and July-August but can be as late as November.

There were active green fresh mines but there were also other older mines, some emptied, which might have been from the first generation, May-June, or already-hatched mines from the second generation. Here is a supposedly typical fresh oval mine of Phyllonorycter klemanella (=kleemannella). 

Here is another mine, from the upper side of the leaf.

Phyllonorycter stettinensis (Nicelli, 1852), the Small Alder Midget

I did also find two, or a few more, examples of Phyllonorycter stettinensis, on the upper side of the leaf. This is yellow green, with one strong central crease, the timing is right for the second generation  but in this photograph it is NOT over a lateral vein, as described in Bladmineerders. A second mine was over a lateral vein, so that is OK!

This mine is apparently much more typical, over the vein,

Phyllonorycter froelichiella (Zeller, 1839), the Broad-barred Midget

I may have found one or two examples of this leaf-miner, but it is a bit early for this particular species. Also this particular mine does look as though there is the start of a single crease in the mine, which would be unexpected in froelichiella, so maybe this is a misidentification. With this crease it could be rajella.

I need to check back, but I don't seem to have ever seen froelichiella for sure - I will check through as much as I can.

.Phyllonorycter rajella (Linnaeus, 17589), the Common Alder Midget

Why haven't I found this species on the leaves of this tree? The larvae should be found in June/July and more in September/October, and I would have expected to find it by now.

Heterarthus vagans ( ), 

This is a possible, but not definite, identification,

Dasineura ulmaria, a Leaf Gall midge on Meadowsweet

 

Possible ID. Found somewhere along the River Bourne walk on a Meadowsweet plant.

Butterflies at Leybourne

Nice walk through the recently created meadows today with the trainee group of butterfly surveyors, and saw one or two Small Coppers, Common Blues, Small Whites, Large Whites, four Painted Ladies and lots of Gatekeepers and Meadow Browns. A possible Red Admiral was seen.

A couple of Speckled Woods over on the path around the Ocean, nice to see.

Iteomyia capreae, a willow leaf gall initiated by a gall midge larva.

 

Found somewhere along by the River Bourne. 

BBQ near Harrietsham

Red Admiral on the lawn, and a nice collection of perhaps rather crowded trees. One of the purple plums had a couple of Ganoderma applanatum brackets on a dead stump. I rubbed the edge of the spore surface and it turned brown immediately - the spores?

Sweet Cicely I thought at the bottom of the garden, in the hedge by the side road.