Saturday, 23 April 2011

Some you win...

After a couple of recent incorrect identifications (of a grass and a spider), I'm a more wary individual. This morning I approached the moth trap with an air of uncertainty. As far as macro moths go, I'm on fairly safe ground. Micro moths are a bit more of a challenge, but I do have accessibility to all of the literature that I need. Other invertebrates are a different matter. Take spiders for instance. I have a copy of the Collins Field Guide to the Spiders of Britain and Northern Europe by Michael Roberts. That, to my small mind, must be enough of a reference to confidently identify anything that comes my way (save for a foreign stowaway in a box of bananas). My assumption is wrong. I've struggled to match the living spider, or a decent macro image of one, with the plates in the guide. Last week's Thursley spider was a case in point. It could be that all spiders are highly variable and that students of the arachnidae look towards other features to get a correct identification other than 'plumage'. I will not be giving up though.

Back to this morning s moth trap. No moths quickened my pulse, but my pan-species list radar was alerted to an ichneumon fly with a dark tip to its reddish-brown abdomen. My only, woefully inadequate reference in print to such beasts is Chinery's Collins Insect guide (which is a great generalists starter). I turned to the ichneumon plate and illustrated was Netelia testaceus, a dead ringer for what I had trapped. I then read the text for this particular species, expecting to be informed that there were several similar species, but was cheered to learn that 'there are several similar species, but only testaceus has a dark tip to abdomen'. Result! A safe tick!

Or is there somebody out there that will tell me otherwise...

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