Goldeneye, in lichen form

Running backwards into the Devils Dyke Pub to get out of the fierce hail certainly wasn’t the intended end to today’s outing. We had been caught out on a grand scale; a band of completely unforecast precipitation left our clothes so sodden that not even a hot chocolate and four-cheese pizza could warm me up. But was it worth it?

Birders may be used to the sight of a goldeneye floating out on a windswept gravel pit or reservoir at this time of year. Although the diving duck breed in trees, the nesting sites are solely in cavities in larger trunks and at latitudes further north than the UK. So, how many British birders can say that they’ve seen a goldeneye in a tree? I doubt many of them – yet as of this morning I can, but not sensu stricto.

The goldeneye lichen, Teloschistes chrysophthalmus, is named after the bright orange apothecia borne on blue-tinged stalks. The apothecia are disks containing the asci, which in turn contain the spores which will be carried on the wind to colonise new sites. Indeed, this is likely to be how the goldeneye lichen arrived in the UK. In the 19th century there were several sporadic records along the South Coast, and this decreased to only two in the 20th century. Yet, since 2007, recolonisation has been in full swing and there have been records from most South Coast counties along with an outlier in Herefordshire. It is still a fairly rare species, but definitely on the increase. It is not completely known what might be driving the recolonisation. Increasing temperatures could be a factor, yet in the early 19th century when well-established populations could be found in the south, it was relatively much colder than modern times.

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The bright orange apothecia really stood out on this drab, dull day

For this sighting I am indebted to @apeasbrain who first found the lichen last weekend and who provided brilliant directions (only the one individual plant has been found so far, like a needle in a haystack). However, it turned out that despite the lichen being the main instigator for my visit to Devils Dyke, it was not the only highlight. Just past the Hawthorn on which the lichen is growing, the path descends into a copse of Ash trees. On one of these trees I managed to spot some movement, out of the corner of my eye. At first glance I took it to be a ladybird larva, but I knew something wasn’t quite right. On arrival home, I realised it was in fact a pre-adult Endomychus coccineus, known vernacularly as the False Ladybird. This was a species I’d been wanting to see for months, so it’s a bit embarrassing that I didn’t recognise it immediately – but coupled with the Teloschistes, the incredibly painful scramble back to the pub once the hail set in was absolutely worth it.

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Teloschistes chrysophthalmus becomes my 100th lichen and Endomychus coccineus my 250th beetle. Together they put me on 69 new species for the year so far, a good pace I think!

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Photo-Stacking at the Angela Marmont Centre

On Wednesday I was very lucky to be able to visit the Angela Marmont Centre at the Natural History Museum in London. The Angela Marmont Centre for UK Biodiversity is an amazing place for naturalists in the United Kingdom that is available for anyone to use. With such a range of resources such as the photo-stacking equipment; a huge library; and the whole of the British collections, it really is invaluable.

I have used the photo-stacking equipment here once before and I really do think it is a very clever piece of kit. It takes lots of photos (I took around 65 for each specimen) all at different focal points and then merges them together using software called Helicon Focus. With all of the different focal points on the specimen covered, there is no part of the specimen that is out of focus and it is all very sharp. This produces a clear image that can show many different features, excellent for identification or illustration of species.

I think that photo-stacking is incredibly useful for a number of projects. For example, if you were writing an identification guide and space was limited, you could in many cases show all the features of an organism in just a single photograph. Also for illustrating an article or a short piece of writing where there is a limit to the number of photographs, you could include just a single image with all of the key features clear and visible.

Below are a few of the photo-stacked images that I took using the equipment. You can find all of the images of the identified specimens on this page. I still have some photographed specimens that I need to identify, and I will post them on that page once I have put a name to them.

Stenodema calcarata labelled

 This Mirid bug is just 8mm from head to end of the abdomen. Its distiguishing feature is the two short spines on the hind femur. This separates this species and the very similar Stenodema laevigata.

 

 

Poecilus cupreus labelled

This is the largest specimen that I photographed, 13mm. This rather big Carabid beetle was swept from a patch of nettles, much to my surprise!

Agriotes pallidulus labelled

This is a very small Elaterid, or click beetle, only 4mm long. When they are threatened they often roll onto their backs and catapult themselves upwards to escape predators and they make a ‘click’ sound as they do so.