Tuesday 10 March 2015

Ground Beetles (Carabids) workshop

When we were kids in the 90's, my bro and I would squabble over who got to be the first to read the new issue of 'Bugs' magazine (I think that was what it was called). It came with free 3D specs for a double-page center image of a terrifying invertebrate, plus collectible glow-in-the-dark pieces of a spider model. It was also where I first read about the obnoxious habits of carabid beetles such as the Bombardier, which can spray a nasty concoction of boiling chemicals from their rear ends into the faces of predators... Those rascals.

Beetle body-plan: the weirdly named Sausage Ground Beetle (Carabus granulatus)

Last Saturday I visited the British Entomological and Natural History Society at Dinton Pastures, Reading to take part in the Ground Beetle (Carabidae) identification workshop. This is the 4th BENHS workshop I've been along to now and each one is uniquely fascinating.

Entomologist John Walters with the BENHS collection of Carabids

Today's course was jointly run by entomologists Mark Telfer (of Pan-species listing fame) and John Walters. It began with a presentation introducing the Carabidae family of beetles and their wonderful diversity in the UK. These include your classic black Ground Beetles, stunning Peacock Beetles, monstrous Tiger Beetles and the relatively tiny Bembidions.

Mark's precisely labelled and positioned specimens

Beetles are like living tanks with awesome customized add-ons which vary depending on their lifestyles. Being almost entirely predatory, carabids are monsters of the undergrowth with huge, curved jaws, massive eyes and spiked sprinting legs... Pimp My Beetle wouldn't work as a TV show, as they are already too damn pimped. 

Carabus granulatus (Sausage Ground Beetle) under the microscope. 
My Sony Xperia phone seems to take fairly good images this way 

The classroom session involved selecting specimens from the workshop collection and trying out different identification books and keys, including handy worksheets produced by Mark and John. These guys are on a mission to make the study and identification of insects (entomology) more accessible to beginners...

A detailed identification key to the features of Carabid beetles

But these brilliant worksheets were much more user-friendly

Superficially similar: Carabus granulatus on the left, Carabus arvensis on the right.

Of course is it always a beautiful day whenever microscopes are involved! Fortunately we had the opportunity to step outside for some live beetle handling/wrangling, learning about useful identification features out in the field:

Beetle wrangling (like a boss)

A live Violet Ground Beetle (Carabus violaceus) in the hand. 

The idea is to firmly grasp the middle and hind legs, which mostly immobilizes them so you can then examine from all angles. Their nip doesn't hurt too bad (unless you have open cracks on the sides of your thumb, then it bloody hurts).

Flipping the beetle

Momentary distraction with 3 Red Kites flying over our heads

At the end of the day, Mark demonstrated mounting a dead beetle specimen onto card... not your classic hallmark type of card (although I bet Mark wouldn't mind receiving one like that).

My first mounted Gatwick beetle specimen: Black Clock Beetle (Pterostichus madidus)

I had a sort through some of the Gatwick pitfall-trap sample jars, in which we had just 2 very common carabid species: Pterostichus madidus and Abax parallelepipedus.

So I'm 2 species down with some way to go before I amass a collection like Mark's. Hmmm, I forgot to ask when exactly he started off...

Mark Telfer's Website : A great resource for beetle identification keys and literature.
John Walter's Website : Beautiful natural history illustrations as well as downloadable identification keys
British Entomological and Natural History Society : Field meetings and indoor workshops, open to anyone with an interest in the astounding diversity of UK insects and other invertebrates.

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