Beetles For Id

[Klaas Reißmann]

Hi Rowan,

carding is a method that is done by more and more coleopterologists in Germany and the other european countries. The convenience is, that there is no needle, that possibly damages any character that is important for ID. If you dissect genitalia, the genitalia is glued on the card and can't get lost. So there even will be no confusion in genitalia owning to which beetle. Your beetles are more secure of damage, because the card bumps into obstacles, not the beetle.

The disadvantage is, you have to identify your beetles before carding, if there are any characters on the downside of the beetle. Or you have to undo the carding and to card again.

In small beetles the chance is very big to damage any characters, so it is useful to card them. Many coleopterologists even card the big ones, but that depends on what you prefer.

Regards
Klaas

P.S.: So you need water-based glue.

[Jason Green]

With bugs, where do you place the pin? I go straight through the scutellum's centre (or slightly off-centre if it's patterned), with little in the way of wing-displacement. I only ever hold insects whilst pinning; tricky yes, but a higher chance of the insect 'pinging' out your grip and ending-up somewhere you'll never find it again if using solid forceps. Your fingers have more 'absorbency' which prevents damage in my opinion. I have yet to damage one!

I'm hoping to get upgraded eye-pieces for my microscope so will be afforded the chance to examine my tiny pinned Apion spp. for damage caused through micro-pinning. I, however, suspect there will be little caused as the pin only affects one side. When I carded-up stuff I hated having to dissolve the glue with water and risk damaging them by lifting-off then re-sticking.

[rowanalder]

Hi guys,

Klaas,

Thanks for the info on carding. A friend of mine uses acetate sheets (Like the old over head projector sheets) as a base for carding so some of the underside characters can be seen. I know that some areas would be obscured by the glue but it seems a good idea. The genitalia stuck on the same card as the insect is a good idea. I need to disect a couple of my specemins so I will give it a go. I might give it a go again next time I get a couple of specemins. Would PVA glue do the job? Thats what I've used in the past.

Jason,

Sorry I ment scutellum not pronatum getting mixed up with my insect anatomy. Sorry I ment using the forceps for putting the pin in, when using the smaller pins I usually struggle to see where the pin is going like in the small Apion weevil in the photo I had not realised that I had put it in the left hand elytra until I looked down the microscope.

Thats a thing I need to do, my microscope is ok for some of the larger species but as for the smaller ones like the Apion I will have to leave them for now, it will help when I start disecting aswell. It does seem a bit of a pain having to disolve specemins off if they have been mis identified and need to see some of the underside characteristics.

Thanks again guys,

Ro

[Jason Green]

Originally Posted by rowanalder

Would PVA glue do the job? Thats what I've used in the past.

You can get water-soluble glue from most craft outlets. The benefits is that you can just add a drop-or-two of water and the clear-dried glue dissolves easily, and if you get a bit covering the genitalia/tarsi or whatever then you can still see through it once dry - unlike with PVA.

[Jason Green]

Originally Posted by rowanalder

...I usually struggle to see where the pin is going like in the small Apion weevil in the photo I had not realised that I had put it in the left hand elytra until I looked down the microscope.

Me too; I've left-hand pinned an Apion before. I've also penetrated a femur and drawn the leg down underneath. Oh, and disconnected a few sternal-plates to leave hanging-off. Still, pinning beetles is no more risky than with wasps or flies. In fact, with beetles less underside characters are used due to the masses carding and so ventral-examination is less called-for.

To me it is more about ease, and uniformity with the rest of my reference collection.

[Matt Smith]

If pinning, bugs should be pinned in the same way as beetles, off centre through the right eltron / hemilytra. Don't center pin as you risk dmaging characters on the scutellum or down the centre line of the insect.

[Klaas Reißmann]

Hi Rowan,

the acetate sheets are an old story. I never tried them, because you have to be very carefully. A guy working on weevils was using them, when he asked for some holotypes of weevils of the Natural History Museum of London. He dissected the genitalia of them all and glued them on acetate sheets. Half a year later, after he send the beetles properly back to the museum, he got those weevils send back, because the genitalia flipped of the sheets and only because he took photographs of them he could relate the genitalia to the right beetles.

I have no idea how to say it, but I try. Fact is, that you can buy two different types of acetate. As far as I remember it was some loaded negativ and some loaded positiv. And on one of them the glue does not stick properly, but flipps of after a while. The idea itself is not to bad, but I, too, think, that so many characters are hidden behind the glue, that there is no real use for this acetate sheets.

But try and error.

Regards
Klaas