Sunday, 27 August 2017

Frack to bunt

Today was a further meeting of the Northamptonshire Diptera Study Group. Two locations were to be visited - Sulgrave and Helmdon. Sulgrave was first up so, stupidly, I went to Helmdon.
No damage was done really because the weather was glorious and I recorded a large number of spiders and insects (actually, to be honest, only a handful of spiders and harvestmen but lots of insects).
The most obvious spider species was the Four-spotted Orb Weaver, Araneus quadratus.

Araneus quadratus. A female on comfrey. Roadside near Helmdon,
Northants. 27 August, 2017

Currently the females are broadly similar in size to the Garden Cross Spider, Araneus diadematus, but once a female A. quadratus is swollen with eggs, a few weeks time, she will be considerably bigger and at one time featured in The Guinness Book of Records as the heaviest British spider. I accidentally netted a Garden Cross Spider and the photograph allows the similarities and differences to be seen.
Garden Cross Spider. Roadside near Helmdon, Northants.
27 August, 2017
The white cross on the back of A. diadematus is actually formed by cells swollen with guanine, a widespread substance in animals and, to a lesser extent, in plants.
Another animal, this time not a spider, was not seen until I discovered it in my net. This was the Bishop's Mitre Shieldbug, Aelia acuminata, and it was not surprising that I hadn't spotted it for it has the shape and colour of a dried grass head.
Bishop's Mitre Shieldbug. Roadside near Helmdon,
Northants. 27 August, 2017

With the next sweep of my net I secured - deliberately this time - a female Oak Bush Cricket, Meconema thalassinum. It is a widespread species with the long female ovipositor typical of the genus. Unfortunately all the specimens in the net proved quite difficult to photograph, while another species, Roesel's Bush Cricket, wouldn't allow a photograph at all but fortunately it is a very distinctive insect. Catching one was quite unnecessary. 
Oak Bush Cricket from roadside nr Helmdon, Northamptonshire.
27 August, 2017
The roadside verges supported a rather good flora with Ragwort, Jacobaea vulgaris, quite prolific and attracting many insects, particularly hoverflies. It is a plant with a bad reputation but even less welcome, particularly along watercourses, is Indian (Himalayan) Balsam, Impatiens glandulifera.
Indian Balsam in damp ditch near Helmdon, Northants.
27 August, 2017
Here it seemed to be content with a damp ditch and formed only a small patch, unlikely to pose a problem, but in some areas such as along the River Nene east of Northampton, it is a rampant weed and it is illegal to introduce it into the wild. It must be admitted that it is a beautiful plant, and bees love it although the cloying fragrance is rather odd.
The insect life was prolific and although I avoid taking specimens unless absolutely necessary (probably letting 99% go free) I still set off home, passing the rest of the recording group going in the other direction, with much work ahead of me.


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