live insects under the microscope

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I’ve been trying out an ‘insect restrainer’ for examining live insects (and arachnids) under the microscope, and am pleased with the results. The restrainer is made from the top half of a glass-topped collecting tin, and a circle of plastazote cut to the same size:

For spiders and some types of insect, the restrainer allows them to be held firmly, but gently, while under the ‘scope for identification and photography. They can then be released, unharmed as far as I can tell. Examples – the big Tegenaria house spiders need close examination of the male palps for identification, and here is Tegenaria gigantea in the restrainer:

And here is the underside of the harvestman Paroligolophus agrestis – the essential character for confirming females of this one is the tip of the operculum, on the underside – easy to do, but only if the creature will lie still, and upside-down, under the microscope or hand-lens:

And a weevil, Aspidapion aeneum, which feeds on Hollyhocks in my garden. For this one you need to see the furrow on the top of the head, between the eyes:

The restrainer makes it quick and easy to check IDs for some species. The photos are not the best quality (they’re taken with a fairly low-spec Canon Ixus 900ti, through the microscope and through the glass lid of the restrainer), but they do make it possible to keep a record of the ID features without having to keep a specimen every time.

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new books

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Had an enjoyable day at the AES Exhibition last weekend, great to catch up with loads of people I haven’t seen for ages. Some new books out too, including:

  • The latest (vol. 5 part 17c) in Mike Morris’s series of weevil keys for the Royal Ent Soc. These keys are becoming much more nicely laid-out and user-friendly since the Field Studies Council started producing them for the RES, and this new key is a great improvement over the keys in Joy, which is probably all most of us have had access to up till now. However, they’re still a challenging group, and not for the first time in this set of keys I hit a problem with a specimen that didn’t really fit the keys. Maybe it’s me getting it wrong of course, but I’ll need to check it next time I’m near a museum.
  • And also the latest in the series of Surrey wildlife atlases, this time on bees, by David Baldock. This covers all the solitary and social bees recorded in the county, and as well as the usual dot maps there are informative species accounts, a very welcome new key to bee genera (by Graham Collins), and a set of 48 superb colour plates. Highly recommended, available from Surrey Wildlife Trust.
  • A new AES book on the larger water beetles, by Peter Sutton. Nicely written text full of anecdotes and clearly showing the author’s enthusiasm for this group of beetles. Keys to the larger species and lots of background information.

new species: moth and fly

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The latest edition (vol. 120(5), Sep/Oct 2008) of the Ent Rec has two papers describing new species for the British Isles:

  • the Raspberry Clearwing moth, Pennisetia hylaeiformis (Lepidoptera: Sesiidae), which has larvae that develop in various species and cultivars of raspberry, and has been found in south Cambridgeshire and north Hertfordshire so far, but no reason why it couldn’t be found in Berkshire as well.
  • Pherbellia stackelbergi, a snail-killing fly (Diptera: Sciomyzidae) so far found only in Ireland, but rather similar to P. brunnipes which has records scattered across the UK.

new species of bug

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A few days ago Ian Thirlwell sent me this photo of a large (18mm long) bug for identification. Ian had found next to his moth-trap in Portsmouth, and rather spectacular it looked too. It is Leptoglossus occidentalis, a species that seems to be turning up all of a sudden on the south coast, with further examples reported at:
http://www.flickr.com/photos/wildhastings/2813195575/

and:
http://www.dungenessbirdobs.org.uk/latestins22008.html

The first British record that I can find was in Weymouth in 2007, see page 2 of:
http://www.hetnews.org.uk/pdfs/Issue%2010_Autumn%202007_820Kb.pdf

Ian’s may be the 6th or so British record, and it is a nice-looking bug, but it may also be the latest invasive pest species to reach our shores, so good and bad news I think.

Update (18 October): there’s more news of this bug at:
http://www.britishbugs.org.uk/index.html

Now being seen inland as well.

reactions to insects

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Spent today manning the Bucks Invertebrate Group stall at a family wildlife fun day for Bucks County Museum. I used a video microscope to show off insect (plus spider, centipede etc.) specimens (alive and dead), plus some quizzes and games.

Most people, and nearly all the kids, were fascinated by the insects under the microscope, but the quiz produced a range of responses. I asked people to sort a selection of insect photos into three categories: good to have in a garden (“friends”), bad to have in a garden (“foes”), or not sure/neither good nor bad. The photos included a range of species, from Garden Snail and Large White butterfly caterpillars to hoverfly and lacewing, bees and wasps, etc. I reckoned that the snail and caterpillars could reasonably be classed as “foes”, but the others were neutral or good. Perhaps unsurprisingly many people (adults and children) tended to put more into the “foes” category. Wasp, ant, and often the bees as well, went straight into “foes”, presumably as people couldn’t get past the fact that they can sting (if you annoy them). And not at all surprisingly the lacewing and hoverfly larvae (see photo) went straight into “foes” on the grounds that people didn’t know what they were and therefore assumed they must be bad.

An answer sheet was provided with some information about what the photographed insects actually did for a living, and this seemed to achieve its task of giving people a little more insight into the benefits of having insects around. But still couldn’t persuade everyone that wasps were a good thing. One adult demanded to know what was the “purpose” of wasps, what good did they do, with the implication that things didn’t really have a right to exist if they didn’t benefit humans. However, she did eventually agree with me that perhaps other creatures had a right to live on their own terms.

Peppered Moth extinction – let’s celebrate!

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I’ve been enjoying Martin Wainwright’s blog (Martin’s Moths) – lots of mothy goodness but also examples and anecdotes about how moths are perceived in a wider cultural context. Martin’s day job is as northern editor for the Guardian, and his latest blog post links to one of his articles, where he correlates the news that more people are living to a hundred with the decline in the melanic form of the Peppered Moth. It’s a fascinating read, and full marks to Martin for getting some proper moth science into a national newspaper article.

However, the language used implies that the decline of the melanic Peppered Moth might be something to worry about – Martin’s article says that the decline “looks terminal” and talks of “extinction” of the melanic form, and I’ve noticed similar language in other articles. I’m not sure what it means to say that a genetic variety of a moth is extinct – presumably the form could reappear if conditions change again (e.g. if sooty pollution were to return)? And in any case, the loss of this form is all good news isn’t it – the reduction in this form of pollution is surely a success story? And the Peppered Moth as a species is still doing okay, thankfully.

There’s plenty of actual species that are declining fast, but the evolution of Peppered Moth forms is something to celebrate for once!