Monday 18 August 2014

Underwings, August 2014

Peacock, Aglais io.  Nymphalidae.   High Elms Country Park, 4 August 2014.
Peacock, Aglais io.  Nymphalidae.   High Elms Country Park, 4 August 2014.
Butterflies that overwinter as adults have underwings that disguise or camouflage them.  They are usually very different from the top sufraces, which are often flamboyant.  This Peacock is probably our most colourful butterfly, but look at this black underwing, with subtle jagged cross-lines.

Red Admiral, Vanessa atalanta.  Nymphalidae.   High Elms Country Park, 4 August 2014.
Red Admiral, Vanessa atalanta.  Nymphalidae.   High Elms Country Park, 4 August 2014.
This Red Admiral is from the same family, the Nymphalidae.  Here, only the hind wing is disguised, with wonderful marbling like the inside of an old book cover.  If you should only be able to see the rear underwings, that whitish blotch at the top distinguishes this species.  Actually, this one does not usually overwinter in this country at all.  Most of those we see have come across from Europe.

Brimstone, Gonepteryx rhamni.  Female.  Pieridae.   High Elms Country Park, 4 August 2014.
Brimstone, Gonepteryx rhamni.  Female.  Pieridae.   High Elms Country Park, 4 August 2014.
 The Brimstone, whose males are bright yellow and whose females are very pale, has a different sort of disguise.  When its wings are closed it looks remarkably like a leaf. 

Silver-washed Fritillary, Argynnis paphia.  Nymphalidae.   High Elms Country Park, 4 August 2014.
Silver-washed Fritillary, Argynnis paphia.  Nymphalidae.   High Elms Country Park, 4 August 2014.
Butterflies that overwinter as caterpillars do not have such a need for disguise, but not all of them are showy beneath.  This Silver-washed Fritillary, a large and pretty butterfly, is relatively subdued.

Common Blue butterfly, Polyommatus icarus.  Lycaenidae.   High Elms Country Park, 9 August 2014.
Common Blue butterfly, Polyommatus icarus.  Lycaenidae.   High Elms Country Park, 9 August 2014.
This is a favourite.  The Common Blue is a delightful sight flitting around a meadow.  The upper surfaces are either blue or brownish with orange spots; the females are quite variable in this respect, but the males are always blue.  The pretty underwings are often on show, but you need to get up close to fully appreciate them.


Wednesday 13 August 2014

Crowborough Moths, July 2014

Argyresthia goerdartella.  Argyresthiidae.   Crowborough, July 2014.
Argyresthia goerdartella.  Argyresthiidae.   Crowborough, July 2014.
 I was able to set out my light trap overnight in Crowborough in July.  It was in a garden in the edge of the countryside and I got lots of nice moths, though nothing rare or unusual.  This Argyrestha is a tiny golden beauty that glints from the trap and can be found all over the place at this time of year.

Peppered Moth, Biston betularia.  Geometridae.   Crowborough, July 2014.
Peppered Moth, Biston betularia.  Geometridae.   Crowborough, July 2014.
This Peppered Moth is much larger and very conspicuous in the trap.  It is the species that is often used, incorrectly, as an example of natural selection.  The idea sounds great, with dark forms suddenly becoming common during the industrial revolution, but actual evidence of disguise against a dark background being a survival factor has not been forthcoming.  This is the most common form, and its foreshortened outline and peppered appearance is unmistakeable.

Oak Hooktip, Watsonalla binaria.  Drepanidae.  Crowborough, July 2014.
Oak Hooktip, Watsonalla binaria.  Drepanidae.  Crowborough, July 2014.
The Hook-tips also have a distinctive shape, living up to their name.  This is the one I see most often, oaks being common in this area, and in Crowborough too.

Knot Grass, Acronicta rumicis.  Noctuidae.  Crowborough, July 2014.
Knot Grass, Acronicta rumicis.  Noctuidae.  Crowborough, July 2014.
This was new to me.  There are several rather similar Acronictas and care is needed to distinguish them.  You can clearly see the black circles which are typical of the family Noctuidae - they almost all have round, or roundish, markings in that position, and a more kidney-shaped mark lower down which is quite vague and faint in this species.

Lesser Swallow Prominent, Pheosia gnoma.  Notodontidae.   Crowborough, July 2014.
Lesser Swallow Prominent, Pheosia gnoma.  Notodontidae.   Crowborough, July 2014.
This one is unmistakeable.  There is also a slightly larger Swallow Prominent, but I have never seen one.  All the Prominents have big crests on their thoraxes.

So, I thought I had a good selection.  I have seen most of these moths in my Hayes garden trap, but not all at the same time or in such numbers.  I am hoping to go back again in August!

This is the trap itself, in the back garden:

Skinner 15 watt actinic moth trap in Crowborough.  27 July 2014.
Skinner 15 watt actinic moth trap in Crowborough.  27 July 2014.
All the kit fits into that shopping bag on the right, making it truly portable, and the battery lasts all night.

This was taken at 5:06 am, around first light, and it wasn't very bright.  The iPhone 5S took it at ISO 400, and the result when seen at full size is full of artifacts and lacking in detail.  Even reduced, like this, look at the top left to see what I mean.  That's an interesting comparison with my main Canon cameras, on which ISO 400 is indistinguishable from anything less, and I regularly use ISO 1000.  But the iPhone gives great results with enough light.

Saturday 9 August 2014

July Moths at West Wickham

Rhyacionia pinicolana.  Tortricidae. West Wickham Common light trap, 16 July 2014.
Rhyacionia pinicolana.  Tortricidae. West Wickham Common light trap, 16 July 2014.
Let's start with the most colourful moths from West Wickham Common.  These were in July's trap, set on the 15th by Barry Gutteridge, who is now resident there.  I went up at first light on the 16th to photograph the catch.

This one, Rhyacionia pinicolana, is a pine specialist, and a particularly colourful Tortrix.  There are a few mature Scots Pines not far from the trap.

Scarce Silver-lines, Benia bicolorana.  Noctuidae.  West Wickham Common light trap, 16 July 2014.
Scarce Silver-lines, Benia bicolorana.  Noctuidae.  West Wickham Common light trap, 16 July 2014.
This is one of our few truly green moths, a Scarce Silver-lines.  All of our larger moths have English names.  Names have recently been assigned to all the micromoths as well, but they are mostly ridiculous and I tend to ignore them.  (For example, the Rhyaciona at the top has been given the name "Orange-spotted Shoot.")  The older names show a bit more knowledge of the moths they apply to and are often idiosyncratic and interesting, which makes them more memorable, too.

This one is on my measuring paper, marked off in 5mm squares.

Dusky Sallow, Eremobia ochroleuca.  Noctuidae.  West Wickham Common light trap, 16 July 2014.
Dusky Sallow, Eremobia ochroleuca.  Noctuidae.  West Wickham Common light trap, 16 July 2014.
This is one I had not seen before.  The larvae eat grasses, and it's not scarce.  There are many others I have also not seen, which I may come across later.

Gold Triangle, Hypsopygia costalis.  Pyralidae.   West Wickham Common light trap, 16 July 2014.
Small but nicely marked.  This one was on the outside of the trap.  You have to check everywhere nearby when sorting out the catch.

Festoon, Apoda limacodes.  Limacodidae.   West Wickham Common light trap, 16 July 2014.
Festoon, Apoda limacodes.  Limacodidae.   West Wickham Common light trap, 16 July 2014.
This odd, squat little moth is from an unusual family.  The larvae are small oval things that live on oaks.  This one is not common, but where it is found it tends to occur in numbers, so in such places you get the erroneous impression that they are quite common. 

We also had a Yellow Shell and two Tortoiseshell Moths, nice and colourful, but covered elsewhere in this blog recently.

Monday 4 August 2014

More Heterostyly

Purple Loosestrife, Lythrum salicaria.   Central stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
Purple Loosestrife, Lythrum salicaria.   Central stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
Back in May 2013 I wrote a post on heterostyly, the way that some flowers have more than one distinct configuration of their anthers and stigmas.  The usual example is the Primrose, which had two configurations known as pin-eyed and thrum-eyed.  Check that old post for examples.

I said then that the Purple Loosestrife is unusual in that it has three configurations.  I had intended to find examples that year, but I never did.  However, recently I visited a spot where there were lots of specimens, and I found examples of all three.  At the top of this post you can see a flower with both long and short anthers, and a mid-length stigma.

It's also clear that the different lengths of stamens have differently coloured pollen, yellow on the short ones and a dark green on the longer ones.  If I find out more about that I will write it up.

Purple Loosestrife, Lythrum salicaria.   Short stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
Purple Loosestrife, Lythrum salicaria.   Short stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
It's not so easy to show the short stigma because it tends to be hidden in the tube at the base of the flower, but here you can see it, and especially in the lower flower, it's clear that it is positioned below the shorter yellow stamens.

I only got one rather scrappy shot of the third configuration ...

Purple Loosestrife, Lythrum salicaria.   Long stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
  Purple Loosestrife, Lythrum salicaria.   Long stigma.  On the River Medway near Hartlake Bridge, 25 July 2014.
But at least it is very clear that this stigma is mugh longer than both groups of stamens.

So I was pleased with this result!  I found a paper on line that said experimental results showed that all the pollen can fertilise any plant, but pollinating within the same flower resulted in lower fertility.

Not all visiting insects can be regarded as potential cross-pollinators.

Hoverfly, Sphaerophoria species, female, on Purple Loosestrife, Lythrum salicaria.  On the River Medway, 25 July 2014.
Hoverfly, Sphaerophoria species, female, on Purple Loosestrife, Lythrum salicaria.
On the River Medway, 25 July 2014.
This little hoverfly, a Sphaerophoria, is delicate enough to be able to pick up single grains of pollen from the petals, and it will also lick the anthers, but it  never goes inside the flower looking for nectar and always stays quite clean.