Longhorn beetle project

Figure 1: What possible delights await me with the R. N. Baxter collection of Longicorns (Longhorn) beetles?

Figure 1: What possible delights await me with the R. N. Baxter collection of Longicorns (Longhorn) beetles?

For the past week and a bit I’ve been working in Entomology with my own project on Longhorn beetles (Family: Cerambycidae).  This is a great project for me to work on as it allows me to go through every stage of the process in dealing with incorporating new insect material into the collection.

Figure 2: These delights!

Figure 2: These delights!

Longhorn beetles are an interesting family of beetles; which are themselves an interesting order of insects.  There are more beetles on planet earth than any other animal.  They make up to 30% of all described animals and there are around 500 recognised families and subfamilies.  Many people are familiar with seeing ladybirds and ground beetles crawling around, but then might be surprised when they fly away!  Beetles have a folded underwing protected by their hard forewings to assist them when they need to make a quick getaway!

Figure 3: If this was a Longhorn beetle wasp mimic of the Voice (BBC's X-Factor alternative); I'd want number 17 on my team!

Figure 3: If this was a longhorn beetle wasp mimic version of the Voice (BBC’s X-Factor alternative); I’d want number 17 on my team!

Longhorn beetles are cosmopolitan (meaning they’re found worldwide) and are often characterised by their long antennae (though confusingly some have short antennae!)  Some of the longhorn beetles that I am working with are wasp mimics; I would definitely do a double take if one of these came flying past!  (Though I would not try and bash it with a rolled up newspaper; my tactic, of leaving a wasp or bee be, has thus far proved the best course of action for me.)  The beetles mimic wasps to try and avoid being eaten.  Anyway, enough Hymenoptera, longhorn beetles, including the titan beetle which some people consider the largest insect of all (body length up to 16cm; sadly not pinned by me), are bloody marvellous!

Figure 3: Cerambycidae; the 'Hob-Nobs' of the insect world!

Figure 4: Cerambycidae; the ‘Hob-Nobs’ of the insect world!

The first step in the process is to pin the beetles.  This requires the ‘relaxation’ of the specimens so that they are less likely to break upon the pin being thrust through their carapace (top right of the forewing if you must know).  I relaxed the beetles by dipping them for thirty seconds to a minute in freshly boiled water.  I felt bad for using so much energy in this process but needs must I suppose!

Figure 4: Pinning insects requires serious concentration and a steady hand.

Figure 5: Pinning insects requires serious concentration and a steady hand.

Once pinned on the plastazote the beetles could be carefully manipulated using forceps and a paintbrush so that the limbs were in the right position.  It’s important that the beetles don’t take up so much room in the case so the antennae were manipulated to run down the body, occasionally using pins to hold them in place.  Unfortunately, sometimes parts of the insect, particularly antennae and legs can come off at any stage in the process.  These can be glued using PVA onto a small piece of card and pinned with the specimen, though they are not usually important identifying characters so it isn’t an issue if they aren’t.  You can also glue important parts back on to the insect, but this is only done with large insects or if the thorax and abdomen have broken apart.

Figure 6: Manipulating this beetle's antennae is a tricky process.

Figure 6: Manipulating this beetle’s antennae is a tricky process.

The insects were pinned with a variety of pin thicknesses depending on their size (some of the small beetles were even pinned using small micro-pins on small strips of plastazote to avoid the possible damage of using thicker pins; these are called stage mounts).  The pins are continental stainless steel pins to avoid the effects of verdigris that I’ve touched upon in a previous blog post.  The copper in brass pins can react with the fats in an insect’s abdomen and cause the insect to fall apart.

Figure 7: Micropins and a magnifying glass (plus an even steadier hand) are required for the really small beetles.

Figure 7: Micropins and a magnifying glass (plus an even steadier hand) are required for the really small beetles.

Of highest importance is that all the information (e.g. date collected, species, provenance etc.) that came with the beetles was pinned next to them and they were assigned a joint number.  This is so that the information can be incorporated onto KE-EMu at a later date, and put onto the new labels.  My next task is to input the information from the beetle’s package onto their new labels.  This is achieved through a convenient label-producing software Dmitri owns.  Once this is done I can accession the beetles and input them onto KE-EMu before putting them into a case with the new labels.  Simples! (Incidentally meerkats are quite partial to a beetle or two!)

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About Trainee Curator

I will be writing a blog about the next twelve months spent as a trainee biological curator based at Manchester Museum.
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One Response to Longhorn beetle project

  1. Anna. says:

    Amazing really what can be done to a long expired beetle. Fascinating.

    Sent from my iPhone

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