Friday, 19 May 2017

Tiger Larva

Larva of Jersey Tiger, Euplagia quadripunctaria.  Hayes, 10 May 2017.
Larva of Jersey Tiger, Euplagia quadripunctaria.  Hayes, 10 May 2017.
 Look at this little beauty, which I found curled up among some bits of grass and other plants I was pulling up. 

Larva of Jersey Tiger, Euplagia quadripunctaria.  Hayes, 10 May 2017.
Larva of Jersey Tiger, Euplagia quadripunctaria.  Hayes, 10 May 2017.
It was curled up and took a long time to uncurl.  It's the caterpillar of a Jersey Tiger moth, a very showy creature that I see large numbers of in my light trap for a few weeks in early summer.  They used to be rare in this area, but no longer.

They are increasing in numbers.  Here's a post on Jersey Tiger moths from 2012, when they turned up in twos and threes.  Last year I had over 30 in my trap one day.

These caterpillars are not fussy about what they eat.

Bright colours are usually a warning to predators that the bright creatures are poisonous or distasteful.  Those hairs have a reputation for being very irritating.  They look a lot like the small spines on some cacti, that can get stuck in your skin and are indeed irritating, so I was not tempted to handle it.

I saw another caterpillar recently, and it's in this post of Jubilee Country Park photos.  That's what you would normally expect a caterpillar to look like.


Sunday, 14 May 2017

Hawthorns

Midland Hawthorn, Crataegus laevigata, and Common Hawthorn, Crataegus monogyna.  Sevenoaks Wildlife Reserve, 25 April 2017.
Midland Hawthorn, Crataegus laevigata, and Common Hawthorn, Crataegus monogyna.
Sevenoaks Wildlife Reserve, 25 April 2017.
Most of the hawthorn bushes we see in the south of England are the Common Hawthorn, Crataegus monogyna.  The bush in the middle distance of this photo is one.  In the foreground is a less common species, a Midland Hawthorn.  Its flowers are just a little more showy than the common sort.  Also, the leaves are in general much less divided.  But this is not the best way to tell them apart.

Midland Hawthorn, Crataegus laevigata, and Common Hawthorn, Crataegus monogyna.  Flowers compared.  25 April 2017.
Midland Hawthorn, Crataegus laevigata, and Common Hawthorn, Crataegus monogyna. Flowers compared.  25 April 2017.
Common Hawthorns have just one stigma in the centre of each flower, and just one seed in the berry later on.  Midland Hawthorns have two or sometimes three stigmas, and two or three seeds in the berry.

Counting stigmas or pips is the only real way to be sure of these.  Because, as is so often the case, you might also come across a hybrid between these two species, Crataegus x media, which has leaves and flowers intermediate between them.  So on the hybrid, the flowers have mostly one, but sometimes two stigmas, and the pips in the berries follow suit.  Here is one we found in May last year:

Hybrid Hawthorn, Crataegus x media.  C. monogyna x C. laevigata. Near Jail Lane, 21 May 2016
Hybrid Hawthorn, Crataegus x media.  C. monogyna x C. laevigata. Near Jail Lane, 21 May 2016
They're common in some places, but often under-reported in the wild because not everyone goes around counting stigmas on hawthorn bushes.  I am told that they have been used in hedging because they are robust, but I have never found the common C. monogyna to be less than vigorous. 

Counting stigmas is MUCH easier than counting the pips, so this is the time of year to look for Midland or hybrid hawthorns them if you are so inclined.  Coloured and double-petaled forms of the hybrid are sold as garden shrubs. 

Wednesday, 10 May 2017

Tentacular Spectacular

Bogbean, Menyanthes trifoliata. Sevenoaks Wildlife Reserve, 25 April 2017.
Bogbean, Menyanthes trifoliata. Sevenoaks Wildlife Reserve, 25 April 2017.
I had to post this photo of the flowers of Bogbean, a water plant in a small pool in Sevenoaks Wildlife Reserve.  The plant looks unexceptional for most of the year.

Bogbean, Menyanthes trifoliata. Sevenoaks Wildlife Reserve, 25 April 2017.
Bogbean, Menyanthes trifoliata. Sevenoaks Wildlife Reserve, 25 April 2017.
It has a short flowering season, so normally you just see these leaves.  But those petals covered with tentacles are amazing.

You can see some of the plant in the background of this photo I took of the same pond in September last year:

New Zealand Pigmyweed, Crassula helmsii.  Sevenoaks Wildlife Reserve, 2 September 2016.
New Zealand Pigmyweed, Crassula helmsii.  Sevenoaks Wildlife Reserve, 2 September 2016.
This photo is of an invasive foreign plant, New Zealand Pigmyweed, which covers most of the edge of the pond.  It has pretty little flowers:

New Zealand Pigmyweed, Crassula helmsii.  Sevenoaks Wildlife Reserve, 2 September 2016.
New Zealand Pigmyweed, Crassula helmsii.  Sevenoaks Wildlife Reserve, 2 September 2016.
But unfortunately it chokes and outgrows any native plant that likes the same habitat.  Here's a quote from the Non-native Species Secretariat:

"Introduced in 1911 as an oxygenating plant for ponds and, since the 1970s, has spread rapidly. Forms dense mats and can impede drainage, causing flooding. Displaces other aquatic plant species and reduces amenity use of the waterbody.

New Zealand Pigmyweed is listed under Schedule 9 to the Wildlife and Countryside Act 1981 with respect to England, Wales and Scotland. As such, it is an offence to plant or otherwise cause this species to grow in the wild."

Friday, 5 May 2017

Some JCP Photos

Scots Pine, Pinus sylvestris.  Jubilee Country Park, 30 April 2017.
Scots Pine, Pinus sylvestris.  Jubilee Country Park, 30 April 2017.
There was a lichen walk in Jubilee Country Park last weekend, led by Ishpi Blatchley, or local lichen expert.  I took the opportunity to take some photos of a range of subjects .. this one shows the male "cones" of a Scots Pine, shedding pollen.  There are lots of little pollen grains stuck to the sort of spider webbing which you can find almost everywhere in the countryside.

Oak Apple gall.  Jubilee Country Park, 30 April 2017.
Oak Apple gall.  Jubilee Country Park, 30 April 2017.
There were several of these galls, looking large and apple-like, on an oak tree that was right behind Isphi as she gave her introductory talk.  I was itching to take a shot but waited until later as that seemed more polite!  These growths are caused by the aptly-named  Oak Apple Gall Wasp, Biorhiza pallida.  There are hundreds of plant galls caused by a range of insects that make plants grow homes for them.  Oaks have more types of gall than most plants.

Larva of Orthosia cerasi, Common Quaker. Jubilee Country Park, 30 April 2017.
Larva of Orthosia cerasi, Common Quaker. Jubilee Country Park, 30 April 2017.
This caterpillar was munching on a Field Maple at the edge of the car park.  It was identified for me later (caterpillars are hard!) as a Common Quaker,  a type of moth that is easy to find early in the year.  I was pleased to get a shot that showed the head and the whole body structure so clearly.  It's not as easy as you might think, because they keep on the move and their heads go from side to side.

Parmelina pastillifera.  Parmeliaceae.   Jubilee Country Park, 1 May 2017.
Parmelina pastillifera.  Parmeliaceae.   Jubilee Country Park, 1 May 2017.
Finally, an actual lichen!  Ishpi was pleased to find this Parmelina pastillifera as she only has three other sightings in the London Borough of Bromley (though it's not rare in the UK as a whole).  This was on an oak branch and Ishpi was drawn to it by its steely glint. 

Parmelina pastillifera.  Parmeliaceae.   Jubilee Country Park, 1 May 2017.
Parmelina pastillifera.  Parmeliaceae.   Jubilee Country Park, 1 May 2017.
I wasn't happy with the photos I took on the day so I went back the next day to improve on them.  I opened the iris and sped up the shutter.  This gives less depth of field, but better sharpness and less motion blur.  (As I take these one-handed, holding the subject in place with my other hand, motion blur can be a problem, especially on a long springy tree branch.)

Those little bumps are isidia, little outgrowths containing both the fungus and alga component of the lichen.  It can reproduce if these growths break off and are scattered.  Their shape on this specimen helps to identify it.


Saturday, 29 April 2017

Sevenoaks Light Trap

Green Carpet, Colostygia pectinataria.  Sevenoaks Wildlife Reserve, 25 April 2017.
Green Carpet, Colostygia pectinataria.  Sevenoaks Wildlife Reserve, 25 April 2017.
This was the first trap of the year at Sevenoaks Wildlife Reserve.  We have been having cold weather, particularly at night, so I didn't expect to see much, but there were 9 life forms in or around the trap.  Four of them were moths .. including this petty Green Carpet, which was resting on the woodwork near the trap.  It's always worth having a careful look around.  Not everything that has been attracted to the light actually goes in.

As well as the moths there was a dead-looking Parent Bug,

Alder Fly, Sialis species. (There are 3 very similar.)   Sevenoaks Wildlife Reserve, 25 April 2017.
Alder Fly, Sialis species. (There are 3 very similar.)   Sevenoaks Wildlife Reserve, 25 April 2017.
an Alder Fly (a type of Caddis fly),

Honey Bee, Apis mellifera.  Sevenoaks Wildlife Reserve, 25 April 2017.
Honey Bee, Apis mellifera.  Sevenoaks Wildlife Reserve, 25 April 2017.
this handsome honey bee, and

Ichneumonid wasp, Ophion species.  Sevenoaks Wildlife Reserve, 25 April 2017.
Ichneumonid wasp, Ophion species.  Sevenoaks Wildlife Reserve, 25 April 2017.
this scary-looking Ichneumonid wasp.  These can deliver a sting, apparently, though I have never been stung by one nor heard from anyone who has.

The other moths were a Brimstone Moth (which I didn't see but which was spotted behind some wiring when the trap was put away), a Common Quaker, a Clouded Drab and this beauty:

Pale Tussock, Calliteara pudibunda.  Sevenoaks Wildlife Reserve, 25 April 2017.
Pale Tussock, Calliteara pudibunda.  Sevenoaks Wildlife Reserve, 25 April 2017.
A Pale Tussock.  They always rest like this with furry front legs outstretched. 

Sunday, 23 April 2017

Two Messed-up Coins

Billon antoninianus of Claudius II Gothicus, 268-270 CE.
Billon antoninianus of Claudius II Gothicus, 268-270 CE.
I occasionally post something about ancient coins.  There are two in this post that I bought recently for very little money.  They both look rather messy and it's hard to make out their designs, which is why they were particularly cheap, though even well formed coins of this era are not at all expensive.

I bought them because they hold information.  You can visualise Roman mints of this era as being very busy and not very discriminating.  The dies they made and used were roughly figured and very stylised.  They didn't filter out mistakes; those went into circulation along with the good coins.

There might have been up to four people working with each die pair.  One would place the blank on the bottom die, which might be held by another worker or maybe fixed in place.  This die would have the head image hollowed out.  Another would place the top die with the reverse image on top of the blank, and yet another would hit it with a hammer, at least once, maybe more than once.

What's happened with the top coin is that instead of the struck coin being cleared out of the way, it has flipped over and has still been half in the die when it was hit again.  So, overlying the head image is part of the reverse design, and on top of the reverse, part of the head.  You can see a sideways image of the crown.

Double strikes are not rare, but they are usually a just a sideways shift of the coin between hits,  so that two similar images are superimposed.  This one is a bit more interesting.

Billon Antoninianus of Tetricus I or Tetricus II, 271-274 CE.
Billon Antoninianus of Tetricus I or Tetricus II, 271-274 CE.
This second coin is more complicated.  One side looks like a mirror image of the other.  A coin has stuck in the lower die, and another blank has been placed on top of it.  This second coin therefore has a normal, raised reverse image from the top die, and a sunken and flipped reverse image on what should be the heads side.  The raised image on the first coin has made a sunken image on this one.  This sort of minting error is known as a brockage.

These are not the only kinds of mint errors.  It is also possible to have a die clash, where there has been no blank between the dies when they have been struck.  This damages the dies themselves, and all subsequent coins made with those dies look wrong.  There's a good example on one of Doug Smith's pages here: Brockages and Clashed Dies which also shows some nice brockages.

You can tell a coin is a die clash if you can find more than one of exactly the same error, as Doug's page demonstrates.  In fact, I have one of the very same type as his:

Silver denarius of Julia Domna, "Emesa" mint, 194 CE.
Silver denarius of Julia Domna, "Emesa" mint, 194 CE.
And at least one other is known to exist. You can see from their outlines that this one and Doug's two are all different coins, but the error is identical.  So they must have been struck from the same damaged die.


Wednesday, 19 April 2017

Suburban Wildflowers

Field Forget-me-not, Myosotis arvensis.  Coney Hall, 10 April 2017.
Field Forget-me-not, Myosotis arvensis.  Coney Hall, 10 April 2017.
I have not been out to any new sites this year, but I keep taking photos of plants I see near my home.  Here are some photos of suburban wildflowers from one particular footpath that runs between two roads.  It's unusually rich in flowers, both showy and inconspicuous.

It's common to find Wood Forget-me-not in the suburbs because it is planted in gardens and seeds itself easily.  But this looks like its field relative, with smaller flowers. 

Field Forget-me-not, Myosotis arvensis.  Coney Hall, 10 April 2017.
Field Forget-me-not, Myosotis arvensis.  Coney Hall, 10 April 2017.
Most of these photos show several wildflowers because they all grow close together.  In this shot, surrounding the forget-me-not are some Cornsalads and, at bottom right, a Common Chickweed.  Just below the centre is a Petty Spurge, which has tiny green flowers that you can only make out in this shot if you already know they're there.

Cornsalad, Valerianella species.  Coney Hall, 10 April 2017.
Cornsalad, Valerianella species.  Coney Hall, 10 April 2017.
This is a bigger specimen of the Cornsalad.  I won't be able to tell the species until it fruits.  It's not at all common and is really a weed of arable land.  I was pleased to find one little plant on Hayes Street Farm last year, and then I could never find it again when it should have had fruits.  This one will be harder to lose track of.

Cut-leaved Crane's-bill, Geranium dissectum.  Coney Hall, 10 April 2017.
Cut-leaved Crane's-bill, Geranium dissectum.  Coney Hall, 10 April 2017.
A Cut-leaved Crane's-bill with a couple of small flowers.  Also in this photo are leaves of some other wildflowers.  In the centre, a Common Field Speedwell.  At bottom right, a Dove's-foot Crane's-bill.  At bottom left, a Lesser Celandine.  Middle left, some small Ivy-leaved Speedwells.

Common Field Speedwell, Veronica persica.  Coney Hall, 16 March 2017.
Common Field Speedwell, Veronica persica.  Coney Hall, 16 March 2017.
Here's a flower on a Common Field Speedwell.  There are half a dozen common speedwells.  You can tell this one by the leaf shape and that it has a single blue flower from each leaf axil.

Cow Parsley, Anthriscus sylvestris.  Coney Hall, 10 April 2017.
Cow Parsley, Anthriscus sylvestris.  Coney Hall, 10 April 2017.
This is just the start of the Cow Parsley season.  Many country lanes will be lined with a froth of white in a week or two.  It's very common and grows fast and well. 

In the foreground are some more Lesser Celandine leaves.  The blue flower in the background is a Garden Grape-hyacinth, and true to its name this is a garden escape.  The wild variety has a much more subdued flower colour.

Green Alkanet, Pentaglottis sempervirens.  Coney Hall, 10 April 2017.
Green Alkanet, Pentaglottis sempervirens.  Coney Hall, 10 April 2017.
This Green Alkanet is one of the commonest of our local wildflowers, as well as being one of the showiest.  It grows furiously all spring and summer, flowering all the time.  You could cut this down today and it would be flowering again in two weeks. 

Behind it is some Groundsel, which has no petals on its small yellow flowers.  In the foreground are some I've already shown: Cornsalad, Field Forget-me-not and Petty Spurge.  Growing up the fence are some stems of Cleavers, not yet in flower.

So, you can actually do quite a bit of botanising along 25 yards of one footpath!  And there are a dozen other species, too,  not all in flower at the same time.