Staphs

ger · #1 (**permalink**) 10-09-2011, 04:22 PM

Can anybody help with these:

The first one keys out as Staphylinus dimidiaticornis is this right??

The next two images (the same species) i get down as far as subfamily Aleocharinae...can't get any further (they are about 4mm long)

I tried the final two images(both of the same individual) but i just get lost in the key!!

Sorry about the poor photo quality. All were taken in pitfalls in dry heath on the Brandon mountains SW Ireland. I was trapping for Carabidae, but I got many more staphs.
Ger

Jason Green · #2 (**permalink**) 10-09-2011, 04:29 PM

I can't comment on the first, but the Aleocharines are a difficult sub-family. I have a couple of these carded-up, but until I have 100x power to examine the tarsal-ratios I won't be able to work on them. Your last looks like a Staphylininae sub-family member - do you have the late Lott's c2010 key?

Are you keeping yours in alcohol, or carding them up?

ger · #3 (**permalink**) 10-09-2011, 08:53 PM

Yes using Lotts key.....compared to the Carabidae...they are a really tough group....i now see why people leave them be!!!! I have a number IDed that i would be fairly sure of, but FAR more that I would not be at all sure of!! They are just so abundant around here they can't be ignored!! They have fascinated my kids ever since they accidently trapped one with a Nebria brevicolus....that poor little blighter lost his head...quite literally.

I'm a teacher...I use Industrial meths for the beetles, dry them and store them in tubes so that i can take them out and show my students!!!....Close up!!!...I would love to card them...but i wouldn't be inclined to let anybody touch them then!!!!

What key do you use for the Aleocharinae?
Ger

Jason Green · #4 (**permalink**) 10-09-2011, 08:59 PM

I think the Aleocharines will be covered eventually by the latest RES series.

What does the meths do?

ger · #5 (**permalink**) 11-09-2011, 12:55 AM

The meths dries them out and shrinks the staphs a little just like alcohol except that the methanol contained within it (ours has 5% methanol added) creates a bit of a health and safety bother as its far more toxic than the ethanol alone...hence i leave the beetles dry out well before handling. I find they suit my purpose that way, of course they are too brittle to move, but they survive being taken in and out of a bottle and being dropped onto a hand quite well....I have baked them in low heat to try get this effect without the alcohol, but the results are...well....
best left unsaid!!!...

Ger

Jason Green · #6 (**permalink**) 11-09-2011, 06:25 PM

I'm still a little confused as to the use of meths. Is this used in the pit-fall or as an alcohol-replacement during storage between examination? Whatever, I really would encourage that you either card them up or do as I do - micro-pin. The Alechorines are often checked for tarsal-ratios, and any liquid that will shrink them may affect subsequent IDs.

Carding is relatively easy and the UK-standard method in specimen preparation. Just relax them in an airtight container with a bit of table vinegar-soaked tissue for a week. Then, laying them on their back open the legs outwards to reveal the ventral surface - and if they stay outwards they are relaxed adequately. Now just turn over and drop on a piece of card thinly pre-glued with something clear and water-soluble then arrange the legs symmetrically, including the antenna and both sets of palps.

To micro-pin, just put an A1 through the right-hand elytron. Not as difficult as it sounds - I had success with a 2mm Tachyporine/Coproporus-type thing. Just set on cork post-pinning, arrange legs as with carding then remove pin+specimen from base after four days then stage on a 10mm Nu-poly block on a large G3. This way, you can do ventral stuff too!

I think storing them dry in tubes will eventually lead to breakage, or at least specimens with legs set over needed anatomical parts.

Just a few thoughts!

ger · #7 (**permalink**) 11-09-2011, 11:22 PM

Thanks Jason,
I will give carding a go!
I thought i had to buy a pile of specialized equipment for it!!!
I was trapping in Ethylene glycol and cleaning them up with meths afterwards. As for changing in size...I find that a killer.... not only when they dry out but when they swell in the pitfall traps (especially those traps that are down for a while). Its a major problem for me since i've started on the staphs as even the ones that are more readily identifiable swell to proportions that are well outside the size allowance for that species....

Oh well!!!
Ger

Jason Green · #8 (**permalink**) 12-09-2011, 02:10 PM

Glad to hear you'll give carding a go. It sounds to me like your specimens swell around the membranous joins between abdominal segments/appndages, and so as the specimen dries these parts will be weak links and the whole insect's structural integrity would be susceptible to breakage when being tipped out of tubes - disaster averted!

Carding can be difficult at first - don't be put-off by a couple of initial failures, the trick lies in relaxing. I find a bit of tissue soaked with table-vinegar in an air-tight container for a week to be fantastic. Card them up under the microscope, of course.

Are you labelling them?

ger · #9 (**permalink**) 12-09-2011, 10:06 PM

Hi Jason,
Yes i will have to label of course, do you have special cases to place them in?
Thanks for all the advice

Ger

Jason Green · #10 (**permalink**) 12-09-2011, 11:01 PM

I forgot to say - once carded, cut them out into rectangles leaving a border around the insect of about 2mm. Really though, once you have a range of sizes of insects just create three templates - one small, then medium and large (though there'll be exceptions).

Now, stick a G3 pin through the base of the card (behind the insect's rear tarsi) and leave only about 5mm between the blunt tip of the pin and top-surface of the card - enough for forceps to grip it.

Labelling - you'll need an indelible-ink pen with a 0.2mm nib (I use Mitsubishi Uni-pin pens) and card of about 200+gsm, preferably acid-free. Write down the date of catch, 6-fig. grid-ref + place name, habitat, capture method and your own name (for space, I just put J. Green). Below this will go the data-label. This will have the sex marked, along with the species name you come up with along with your name or that of a determiner, and the year of determination. Both now go under the specimen-card. My labels are 12mm-square, practice writing carefully and check others can read them.

I use a museum-style glass-lidded and plastazote-lined box for mine, about 20x30cm I think, about £18 from Watkins & Doncaster.

Try to get a few varied expert opinions on your labelling and carding before you do too many in case you wish to add more text to labels or arrange insects differently. I currently ned to re-do about 120 specimen's labels because the original ones didn't contain everything they should! Nightmare job, it was originally 330! Ouch...