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 Pinning flies and wasps and some curious questions.
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| ChrisR |
Posted on 12-09-2007 19:16
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 Administrator Location: Posts: 7699 Joined: 12.07.04 |
Yes, keeping flies in 98% (absolute alcohol) is usually only necessary if they are being used for DNA analysis. This grade of alcohol will dehydrate specimens more and will also be more difficult to curate because the spirit evapourates too fast. Diluting it to 70% slows down evapouration and dehydration, but for soft-bodied flies it is always preferable to take them through a rehydration/extraction process to prevent the specimen from shrivelling up when the alcohol evapourates. But for tachinids I haven't found this necessary.  |
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| jorgemotalmeida |
Posted on 12-09-2007 19:43
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 Member Location: Posts: 9295 Joined: 05.06.06 |
yes. I know.  I will send some for DNA analysis. |
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| crex |
Posted on 04-10-2007 11:21
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 Member Location: Posts: 1996 Joined: 22.05.06 |
Very informative thread. A few more newbie questions. - How do you hold the flies when pinning not to break bristles etc? They are generally quite fragile, I believe. - How do you arrange the legs and wings in the right position? I think lepidopterists use (rice) paper to pin down the wings when drying. - How do you know what pin size to use? Are there a rule of thumb for this? - If killed in alcohol. Can the flies be pinned directly or do they need to be dried first? ... or maybe you never pin flies that have been in liquid? |
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| jorgemotalmeida |
Posted on 04-10-2007 11:56
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Member Location: Posts: 9295 Joined: 05.06.06 |
"How do you hold the flies when pinning not to break bristles etc? They are generally quite fragile, I believe." I put the fly on the table and simply I push the pin manually against the table (of course, I use a protection to avoid damage for table).  Then I use another pin to help putting the fly in the middle of the pin. Of course, I do this with 100% concentration and holds the fly very gently. There are specific FORCEPS SOFT that can help you to handle soft and very fragile specimens. "How do you arrange the legs and wings in the right position? I think lepidopterists use (rice) paper to pin down the wings when drying." Gently with a forceps soft, for example. Or with a normal pin! "If killed in alcohol. Can the flies be pinned directly or do they need to be dried first? ... or maybe you never pin flies that have been in liquid?" YES. You can pin the flies even AFTER they have been in ethanol. |
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| crex |
Posted on 04-10-2007 15:08
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Member Location: Posts: 1996 Joined: 22.05.06 |
jorgemotalmeida wrote: Newbie wrote: How do you arrange the legs and wings in the right position? I think lepidopterists use (rice) paper to pin down the wings when drying. Gently with a forceps soft, for example. Or with a normal pin! I guess the fly must not be too dry to be able to adjust the wings. I thought the wings (and legs) might revert back to original position when trying to move them. There must be a reason the butterfly collectors use pin and paper to set them in the wanted position. |
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| jorgemotalmeida |
Posted on 04-10-2007 15:33
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Member Location: Posts: 9295 Joined: 05.06.06 |
crex wrote: jorgemotalmeida wrote: Newbie wrote: How do you arrange the legs and wings in the right position? I think lepidopterists use (rice) paper to pin down the wings when drying. Gently with a forceps soft, for example. Or with a normal pin! I guess the fly must not be too dry to be able to adjust the wings. I thought the wings (and legs) might revert back to original position when trying to move them. There must be a reason the butterfly collectors use pin and paper to set them in the wanted position. right, crex. It is important to pin the fly very early because they turn very brittle with the time. Not just for wings, but bristles as well. |
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| ChrisR |
Posted on 04-10-2007 16:54
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Administrator Location: Posts: 7699 Joined: 12.07.04 |
The way people arrange a specimen when it is pinned is largely dependent on the way the insect is identified. Lepidopterists mainly use wing pattern so it's important to arrange the wings so all 4 are visible. With Diptera it isn't so important to pin them like that and in fact I prefer specimen side-pinned with wings at 45-degrees so that areas under the wings (the legs and pleurae) are also clearly visible. How do you hold the flies when pinning not to break bristles etc? They are generally quite fragile, I believe. Flies are quite soft and floppy until they have dried so any pinning and arranging must happen while they are soft and pliable. In a relaxed state they can be handled easily with pointed forceps. Once pinned the specimen is always held using the pin. How do you arrange the legs and wings in the right position? I think lepidopterists use (rice) paper to pin down the wings when drying. I side-pin into a sheet of foam and if anything needs holding (not wings - usually genitalia or legs) I use more small pins, crossed to hold the parts firmly. How do you know what pin size to use? Are there a rule of thumb for this? In general you should use the largest diameter pin you can without damaging the specimen (within reason). It is a thing you learn with experience and by seeing other specimen collections though. My advice is to go to a museum and ask to see their collections. If killed in alcohol. Can the flies be pinned directly or do they need to be dried first? ... or maybe you never pin flies that have been in liquid? Flies out of alcohol tend to be fairly floppy but stiffer than if freshly caught. The worst thing with alcohol is that the genitalia are usually locked fairly tightly and when the alcohol evapourates some soft-bodied flies can dehydrate and crumple. I am lucky because tachinids don't usually have this problem so they would just need to lay on some paper for a few minutes to drain away most of the alcohol and then thay can be pinned. Chris R. |
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| romunov |
Posted on 25-03-2009 10:55
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Member Location: Posts: 52 Joined: 13.02.09 |
Would be nice to see some of your flies being pinned and drying. Mine look like they're being give a session of acupuncture. |
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| romunov |
Posted on 13-04-2009 16:12
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Member Location: Posts: 52 Joined: 13.02.09 |
Is there a preference for fixating the specimens (poison, freezing...)? Has anyone noticed any up or down sides of any method? |
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| Johl Daniel |
Posted on 26-04-2009 14:07
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Member Location: Posts: 6 Joined: 22.04.09 |
I like Tony T's collection Johl daniel |
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| Tom van Noort |
Posted on 12-04-2012 10:02
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Member Location: Posts: 2 Joined: 12.04.12 |
I find the boxes from www.ento-meier.de superior. They are quite expensive though. www.kabourek.cz has good stuff too. |
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| Martin Cooper |
Posted on 03-05-2012 22:53
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Member Location: Posts: 628 Joined: 01.05.12 |
Hello Dipterists, Just a quick post to say how useful I have found this thread. So far I've just examined flies that have died and fallen to the floor of my conservatory. However they are fragile and hard to manipulate to check features against the keys. So I'm thinking that maybe I should join the mainstream and start pinning fresh specimens. On the basis of this thread and Chris Rapers excellent article at http://chrisraper...rating.htm I have placed an order for pins, plastazote and forceps with Watkins and Doncaster, along with a drilled pinning block to standardise the positioning on the pins, although I have only the haziest idea of how to use this. Thanks to Diptera.info for providing such a valuable resource! Martin |
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| ChrisR |
Posted on 03-05-2012 23:35
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Administrator Location: Posts: 7699 Joined: 12.07.04 |
Welcome to the forum Martin - I'm glad you enjoyed my article. I am planning more in the future that should cover other aspects of entomology and expand on some of the stuff I started in my blog. Feel free to message or email me if you want to ask anything. There are some very good dipterists in your part of the world so I'm sure you'd be welcome to go out in the field with some people this year.
Manager of the UK Species Inventory in the Angela Marmont Centre for UK Biodiversity at the Natural History Museum, London. |
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| rafael_carbonell |
Posted on 30-09-2012 13:52
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 Member Location: Posts: 648 Joined: 23.03.06 |
@Chris I have began to pint flies laterally, but all the way, my main problems are in how to shape legs unfolded downwards and wings at 45ยบ. I do some "acupunture" with small pins to fix the legs in the best way and wait some minutes. I usually take them out of Barber liquid (a relaxing liquid, it might work as well as ethyl acethate). I am working with flies collected in liquid traps (a solution to attract the olive fly) so I got hundreds of Muscidae, Sarcophagidae and Calliphoridae and, I has short experience, I found the legs folded in the body and is quite difficult to see the meron. Is there an easy may to manage with them? |
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| ChrisR |
Posted on 30-09-2012 14:40
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Administrator Location: Posts: 7699 Joined: 12.07.04 |
@Rafael I tend not to worry too much about making the wings and legs perfect but if you do want to make sue that the meral bristles are visible then I think you are doing the correct thing - use micropins to hold them in the correct position. The advantage of lateral pinning is that this kind of manipulation (and more importantly the male genitalia) is possible because you pin it against a large piece of foam. When you get more experience you won't need to look for meral bristles - you will just know which family the flies fall into. I know of Barber's fluid but I tend to use normal water - just make some tissue paper wet and lay the flies onto it for 24-36 hours. Ethyl-acetate has the opposite effect - it dries specimens and makes them harder and more brittle. That's why you tend to only use ethyl-acetate on greasy specimens that are already pinned The most important thing to work on with sarcophagids is to expose the male genitalia - you can ignore the females if you have lots of good males. When sarcophagids are not soft they will be very hard to manipulate, so try to pin them as fresh as possible or very well relaxed otherwise you will rip-off the genitalia, trying to fold them open
Manager of the UK Species Inventory in the Angela Marmont Centre for UK Biodiversity at the Natural History Museum, London. |
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