Wednesday, 5 September 2012

Enough for a page

At last I have enough to fill a page.

The Angelica is sadly going to seed now, and I only managed a few visits in dry weather. This is one of the many male wasps that have been thrown out of the nests to forage for themselves:

Male wasp on Angelica
These males can be recognised by their long, droopy antennae and their slow movement over the flowerheads.

Leucozona glaucia has certainly been scarcer this year. I'm not sure if this has been caused by last year's excessive rain or this year's excessive rain.

Leucozona glaucia hoverfly

Amblyteles armatorius is one of the few Ichneumonids that can be identified without microscopic analysis:
The Ichneumonid Amblyteles armatorius
There are many similar species, including Ichneumon extensorius, which has the same colouration, but is half the size, at around 10-15mm long.

One of the problems with identification of Mirid bugs is that some of them change colour in the later part of the season, so there are different confusion species at different times of the year. Stenodema holsata is brown in its first season, but will be green next year:

Mirid bug Stenodema holsata
New to my Species Index.

Compare with Stenodema laevigata (which is longer and thinner) on this earlier post.

I was working a line of Alders tonight and found this mine:

Mine of the Agromyzid fly Agromyza alnivora on Alder
Agromyza alnivora is a rarely-recorded fly with a wide distribution range, and I have only found it twice. Alder is a very common tree, so there must be some reason for its scarcity. I notice that the mine is very long and tortuous, starting near centre-right and wandering roughly clockwise twice before descending down the right-hand side to the crescent-shaped exit point (bottom centre).  This is a very much longer mine than I would expect to see from a miner of this size, so I can only assume that it is a very inefficient feeder (Alder is clearly a very nutritious plant, given the number of species that feed on it). This, in turn, will increase opportunities for competing organisms to dominate and for parasites/predators to attack. If I had to hazard a guess, I would say that this is a species that is relatively new, or is on the way out.

The Peacock butterfly relies on Nettles for larval food, so I'm always a bit puzzled that I see most of my local specimens in an area where there are no nettles (that I know of) for hundreds of metres in any direction.

Peacock butterfly
This area is at the edge of recently-harvested coniferous plantation, so perhaps there is some 'memory' of nettles in previous decades.

Moths to light include:

Large Yellow Underwing (a clear sign of the progressing year):

Large Yellow Underwing
Rosy Minor:
Rosy Minor

The extremely variable Common Marbled Carpet:

Common Marbled Carpet

And a new (to me) micromoth:

Epinotia nisella

Epinotia nisella is a Willow feeder. This specimen is not of the usually-illustrated form, but is more like the mainland European specimens.

New to my Species Index.

1 comment:

Gill said...

"Leucozona glaucia has certainly been scarcer this year" - it certainly has, I've only seen one (and that wasn't very bright blue) which is a shame as it's one of my favourites.