Thread subject: Diptera.info :: New trip

Posted by Nikita Vikhrev on 27-05-2007 05:34
#1

Andrey Ozerov, Black and me have just come back from 2 days trip in "Central Chernozemny Nat Res". It is 550 km south Moscow and it is a very rare site of undisturbed (never ploughed) wet step with oak forest in low places.
Nobody worked with Diptera fauna there so far.
Altougether we pined around 1000 of flies.
Image: step with Stipa pennata (Stipa joannis) and Salvia nutans.

Posted by Nikita Vikhrev on 27-05-2007 05:37
#2

image

Posted by jorgemotalmeida on 27-05-2007 16:41
#3

1000 flies??? :o:o:o
you are very crazy. :)B)

we are very curious about the most unusual flies over there. ;)

Posted by Nikita Vikhrev on 29-05-2007 08:22
#4

Unfortunely not as crazy as I wish, final count gave 600 flies only:(

Posted by ChrisR on 01-06-2007 22:40
#5

You need a bigger net! ;) But seriously, unless you run malaise traps it's not easy to hand-catch diptera and be selective about the orders you catch - so it's a pretty good catch for 2 days :) Any more habitat photos? Looks really intriguing.

Posted by Kahis on 31-07-2007 23:49
#6

Sorry about waking an old thread, but I missed it the first time around.

600 flies sound about right in my experience :) My daily (pinnd) catch when hunting full-time is around 100-150 flies per day if weather co-operates. 100*3*2 = 600 :)

The fact that I am not picky about families helps a lot. But micropinning all those chloropids and (worse) agromyzids takes a lot of time which cancels out some of the gain ;)

Posted by Paul Beuk on 01-08-2007 06:17
#7

Hehe, why start pinning if you can put them in alcohol. Much less labelling as well. :P

Posted by Nikita Vikhrev on 01-08-2007 07:52
#8

put them in alcohol means that someday in future you will have a free time to pin. My experiens show me that such a "sunny future" never exist in reality, so I found that to do everything "here and now" is the best rule for me:D
Nikita

Posted by Paul Beuk on 01-08-2007 11:56
#9

Why would I pin them at all? Material most often is easier to examine in alcohol. The only problem is dusting that in some groups is poorly visible by a quick (but not complete) dry of the specimen solves that problem.

Posted by Susan R Walter on 01-08-2007 14:13
#10

I thought wet specimens meant problems if they had soft hairs that would get matted, or long hairs which lose their natural aspect ie sit flat and stuck to the body, when in life they would be more upstanding, and quite often the direction a bristle is pointing is an important character.

I'm curious because it looks like I might acquire a load of wet specimens from central France - the by product of someone else's beetle surveying using vane traps.

Posted by Tony T on 01-08-2007 18:52
#11

I think storing Diptera in alcohol that are intented to be pinned in the future is a bad idea. As Susan said, hairs matt; and oils and fats are likely to dissolve out of the specimen and cause staining of the cuticle. Also the flies become brittle. I collect flies alive individually in small plastic vials. About every 30 mins. if the day is hot (above 25 C) I transfer the vials to a cooler. They will remain alive at 5 C for several days if necessary. Flies are then labelled and placed in a freezer, -19 C, until I have time to process them. Out of curiosity I just took out a 10.5 mm muscid that was collected 7 May 2007. It looks like it was collected yesterday, legs are still flexible.

Posted by Nikita Vikhrev on 01-08-2007 19:04
#12

1. Soon I will get material collected by my friend in Siberia, in alcohol. So, I will try how it is.
2. Meanwhile I pin and will pin. May be I'm oldfashioned, may be I'm semiChinese - I like tradition:D
Nikita

Posted by Paul Beuk on 01-08-2007 19:14
#13

Susan R Walter wrote:
I thought wet specimens meant problems if they had soft hairs that would get matted, or long hairs which lose their natural aspect ie sit flat and stuck to the body, when in life they would be more upstanding, and quite often the direction a bristle is pointing is an important character.
That is what you get when you transfer specimens from alcohol to dry air to be pinned without any treatment. The higher the alcohol percentage, the less effect you will see on ahirs and pollinosity, though you might see shriveling of legs and sinking of eyes in relatively soft species.
There are at least two ways to prevent significant distortion of specimens in the way you described, though there may be some other changes apparent. First is critical point drying, second is a series of treatments the treat specimens that dry by air temperature using other chemical sthan alcohol, which will leave them in near perfect shape as well (colour may be slightly affected). I will see what I can dig up on papers and if I can put them in the downloads.

I'm curious because it looks like I might acquire a load of wet specimens from central France - the by product of someone else's beetle surveying using vane traps.
As long as the material remains wet, there should be no problem.

Posted by Kahis on 01-08-2007 19:27
#14

Nikita Vikhrev wrote:
1. Soon I will get material collected by my friend in Siberia, in alcohol. So, I will try how it is.
2. Meanwhile I pin and will pin. May be I'm oldfashioned, may be I'm semiChinese - I like tradition:D
Nikita


There are several ways to dry & pin alcohol-stored material. Freeze-drying and vacuum-freezing gives almost perfect results, but it is expensive and time-consuming.

As a quick&dirty alternative I have used a acetone bath. Specimens are removed from alcohol, pinned while wet, and then immersed in acetone overnight. The time isn't critical, a few hours is enough for small species and times up to several days cause little apparent harm. Later the flies are removed from the acetone. Ay this time the wings of many smaller flies will fold; resting the wings against some thick paper and carefully moving it will usually open the wings. The paper should not be very absorbent, otherwise it will drain all acetone away before you have time to sort out the wings.

There also downsides: acetore-processed specimen are often slightly paler than natural and very brittle. I do not know how well they keep with time; the oldest syrphids processed this way are about 5 years old and they show now long-term harm.

A few hours in acetore will also help preserving colours of many semi-transparent yellow diptera like Lauxaniidae, Drosophilidae, Syprhidae. I do this regularly with nearly all yellow species if I have the time. An acetone bath will totally stop the darkening from from many syrphid suffer during drying especially the handsome Chrysotoxum are prone to turn almost black :(

If you are interested in more details, I could prepare a article on this site with photos of the equipment I use for this purpose.

EDIT. Oh yes, you need to use fresh acetone. As soon as it turns slightly yellowish from grease, fine hairs will start to stick together when dry and you'll get ugly specimens.

Edited by Kahis on 01-08-2007 19:33

Posted by Paul Beuk on 01-08-2007 19:36
#15

If you are interested in more details, I could prepare a article on this site with photos of the equipment I use for this purpose.
What are you waiting for... :D

Posted by Kahis on 01-08-2007 19:53
#16

Paul Beuk wrote:
If you are interested in more details, I could prepare a article on this site with photos of the equipment I use for this purpose.
What are you waiting for... :D


Money. Fame. Respect. Unconditional love. The usual stuff :)

But first I have to catch some demo flies. I'll be back in a few days.

Posted by Paul Beuk on 01-08-2007 21:21
#17

Kahis wrote:
Money.
at chance here.
Fame.
Having recenyly passed the 1000 mark in posts here, you must have it.
Respect.
See previous.
Unconditional love.
Just come and get that hug. If you insists I might throw in a couple of kisses as well. :P
The usual stuff :)
You can get that in the grocery shop around the corner. At least, that is where I get mine. :D

Posted by Susan R Walter on 02-08-2007 12:41
#18

Thanks guys, with a big smoochy kiss to Jere if that's what he needs to get through the day. A useful discussion, and I will certainly try the tip about acetone for yellow diptera.

Tony's method is exactly as I used to do, and ideal for me, but unfortunately, my husband did not grow up in a household where dead fauna was habitually kept in the freezer, and last year objected so strongly at the build up of specimens by the end of the season that I had to change tactics. This year I have resorted to freezing specimens to kill them, quickly pinning anything that is really important, and keeping the rest loose in small containers.

To be honest, I am not sure what sort of condition the French material is going to turn out to be in, but I had assumed I might need to keep it permanently in alcohol.

Edited by Susan R Walter on 02-08-2007 13:47

Posted by jorgemotalmeida on 02-08-2007 14:05
#19

Kahis wrote:
Money.


Paul Beuk wrote:
at chance here.


Is it really possible to get money doing articles for diptera.info??


Kahis wrote: Fame. Respect.

Paul Beuk wrote:
Having recenyly passed the 1000 mark in posts here, you must have it.


I think Jere is famous here. :) Undoubtely.


Kahis wrote:Unconditional love.


Paul Beuk wrote:
Just come and get that hug. If you insists I might throw in a couple of kisses as well. :P



LOL :D That's the real LOVE! B):D:D Then you can slurp a little saliva... :D lol


Kahis wrote:The usual stuff :)


Paul Beuk wrote:
You can get that in the grocery shop around the corner. At least, that is where I get mine. :D


LOL :D or through the net. :P

Posted by caliprobola on 02-08-2007 14:52
#20

You can get that in the grocery shop around the corner. At least, that is where I get mine.
but Paul lives in the Netherlands you know, that's where all the Belgians get their usual stuff too :D

Posted by Paul Beuk on 02-08-2007 15:45
#21

jorgemotalmeida wrote:
Kahis wrote:
Money.


Paul Beuk wrote:
at chance here.


Is it really possible to get money doing articles for diptera.info??

Should have read: Fat chance here.

Posted by Paul Beuk on 02-08-2007 15:46
#22

caliprobola wrote:
You can get that in the grocery shop around the corner. At least, that is where I get mine.
but Paul lives in the Netherlands you know, that's where all the Belgians get their usual stuff too :D
I guess that tells us more about you than about me. :D

Posted by caliprobola on 02-08-2007 15:57
#23

... i get my kicks out of flies nowadays :D

Posted by Tony T on 03-08-2007 03:20
#24

Kahis wrote:

As a quick&dirty alternative I have used a acetone bath. Specimens are removed from alcohol, pinned while wet, and then immersed in acetone overnight. The time isn't critical, a few hours is enough for small species and times up to several days cause little apparent harm. Later the flies are removed from the acetone.

Read the rest of Kahis's comments.

Acetone is the standard way to preserve Odonates and also to 'freshen up' just about any insect. It is extensively used for degreasing Lepidoptera. I wrote a short article on such degreasing and am including 2 of the figures here to illustrate part of the method. 1] Obtain a polyethylene dish just deep enough to accommodate an insect pin; 2] Make a hole in the top to hold a wine bottle cork; 3] Pin the fly into the cork (Fig 3); Fill the dish with enough acetone that it just covers the fly when the lid is placed on the container (Fig. 4).
For flies one could use many smaller corks in the lid and thus 'freshen up' many flies at once.

Posted by Smoggycb on 19-04-2008 16:28
#25

I recently (yesterday) got my hands on a small number of flies from a water trap that I immediately put into alcohol. With such a short immersion time in alcohol, could I get away with pinning them soon without any of the treatments described above?

Posted by ChrisR on 21-04-2008 00:47
#26

I'd guess so - it usually takes a while (a week?) before the alcohol completely drives out the water from the specimens. I used to get quite good results if I pinned after just 3 days in alcohol but leave them in for weeks/months more and you have more shrivelling. But you'll only know for sure if you try one ;)

Posted by Steve Pelikan on 25-04-2008 22:20
#27

I've had to work with lots of flies from water traps recently and found that if I manipulate them into a decent posture while hydrated, transfer them to 90% isopropanol for a while (a day or so dries 'em out pretty well), let them air dry, and mount them on points or with adhesive to the side of a pin, I end up with usable specimens.

Though I admit: dusting and aspect /posture of fine hairs isn't important for my taxa.

The whole process is actually faster per specimen that pinning freshly collected flies. And gluing them to a pin makes them smaller in a drawer.

Posted by Smoggycb on 26-04-2008 01:09
#28

Thanks Chris and Steve. They seem to have pinned out rather well, and while I haven't looked at them properly yet the dusting doesn't seem to have come out of it too badly after such a short immersion in alcohol. A pleasant surprise!