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Post by luehdorfia on Aug 15, 2017 15:51:03 GMT
I have a strange problem with the very fresh Brimstone females that I caught last year. They were super fresh, probably the first day on the wing last year with their delicate whitish cream colour. When I looked at them in the display case one year later I could not believe my eyes. Some how the wings have become a greenish colour that seems to get inside the wing from the outer wing and slowly crawls into the center. I have put them into the case after they were completely dry. They were deep-frozen for two weeks before I put PDB into the case. No other specimens in the same display case show any signs of humidity, or any discoloration, they are also stored super dry in a cupboard. I really cannnot explain to myself what is happening here.
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Post by luehdorfia on Aug 15, 2017 15:53:07 GMT
In order to see it better I increased the contrast, so that you see it at once. In reality it is really easy to see and the green is not normal in fresh females.
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Post by Adam Cotton on Aug 15, 2017 17:13:22 GMT
I wonder whether this is a chemical reaction between the wing pigment and PDB.
Adam.
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Post by Paul K on Aug 16, 2017 0:24:47 GMT
I wonder whether this is a chemical reaction between the wing pigment and PDB. Adam. It is quite possible, I've heard it somewhere before but in regards to dichlorvos. I used both but never have any problems. ... I have to go check my female Paul
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Post by trehopr1 on Aug 16, 2017 3:33:10 GMT
I wonder if the extreme cold which you subjected these fresh specimens to --- is the culprit here. Perhaps a chemical reaction between the fresh pigments and cold. One could stretch one's imagination a tad and say that superficially the specimens look like they have "frostbite" which is gradually spreading.... Maybe, this is not so far from the truth. Speaking for myself, I have had very few occasions or reasons to ever freeze anything. My material comes off the spreading boards and is transferred to some Schmitt boxes that I have until I have time to actually add them to the main collection. Usually within a month I then add them; which is when I do my final check for any un- wanted guests/pests. I don't fumigate the "holding boxes" because it is during their month stay that I want any potential pests/ larvae to show themselves among the soon to be added specimens. This technique has worked for me without fail. My specimens than go into insect drawers which have naphthalene. If I get something in trade or from an old collection than they also go into the "holding boxes" for a month.Of coarse, I check the boxes for activity weekly to nip any potential problems --- in the bud. I will also add that I have always found the color white and green to be particularly sensitive to just about everything; especially light, humidity, chemical off-gassing, and body oils. I think that by adding extreme cold to the mix "without having credible evidence of specimen infestation" than you are accidentally just providing another factor that could go wrong on some specimens. I can well picture that specimens exposed to extreme cold for a week or two might develop frost on the outer margins of their wings as well as legs and antennae. Even if it is not necessarily visible to your naked eye.
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Post by Paul K on Aug 16, 2017 4:02:27 GMT
Actually my female is also with a little tint of green rather than creamy yellowish but the wings are evenly coloured. It could be just the pigment problem. When specimen is aging it changes the colours. Blue/greenish Graphium sp. are good example as they turning yellow.
Paul PS I have noticed that your male also starts to get green.
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Post by luehdorfia on Aug 16, 2017 5:04:36 GMT
Thanks for your answers. Yes I can see that the male also starts to get a little bit green, I will continue to watch this, and see what happens in half a year, losing these females is not nice but still not as bad as if that had happened to something very rare.
It could probably be both, the deep temperature and the PDB, the wings were really really fresh, they even still had a little silvery shimmer on them, perhaps that's why they could react with the PDB or these very fresh scales could be hurt by deep temperatures. Perhaps I will try again with a reared female next year, to find out why that happened and to avoid something like that in the future.
It's still really sad... they were so nice, it's so rare to catch anything wild that fresh and then the whole small series on the same day, one batch.
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Post by luehdorfia on Aug 16, 2017 5:06:37 GMT
My reason for deep freezing specimens is that we have this tiny tiny dust mites that you can't see normally, and when I leave my specimens on the spreading boards too long without any precautions then I directly have damaged scales...and to kill the dust mites before putting them in the collection I freeze them and then use PDB
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Post by trehopr1 on Aug 16, 2017 5:46:58 GMT
Luehdorfia, perhaps what you have at work on your drying specimens are actually Psocids (book lice); not necessarily dust mites. You mentioned that you place your drying specimens in a cupboard as they dry. The perfect place for Psocids. It is a dark place with other adjoining cupboards which may house food or even old shelving paper and the adhesive which holds it in place. All of this is acceptable food to Psocids. Bookshelves are also notorious havens for psocid activity. Starch is present in book bindings . Try buying yourself a good 3 or 4 large clear Tupperware containers with clear lids and locking down handles. Large enough to hold 1 or 2 of your spreading boards each. They only need to be 7 or 8 inches high. Place each board in the container for drying and toss in 5 or 6 naphthalene moth balls. Should never again have an issue with pests or the need to freeze.
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Post by nomad on Aug 16, 2017 7:29:49 GMT
Brimstones are in fact a greenish-white. I believe the pigment has just darkened in the drying process, the colour is even and I see no problem with your specimens! Having seen a lot in museums they are pretty normal to me.
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Post by luehdorfia on Aug 20, 2017 16:18:18 GMT
nomad I hope so, but I still do think that the females changed their color slightly, and I think I solved the mystery, on another photo I saw that I put some moth stripes into the same box, they are made of green paper... I think the PDB might have somehow damaged that moth stripe and some of the green pigment got into the very fresh brimstone wings.Next time before using PDB I will take everything else out of the box. trehopr1 thanks for that idea, you are probably right. We have hundreds of books in the room where I spread my specimens, I even placed the spreading boards sometimes on top of bookshelves since it was really hot during summer and I thought five or six days will not do any damage, I never saw any book lice. Do the tupperware containers have to be airtight? How will the specimens dry if it is an airtight container?
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Post by luehdorfia on Aug 20, 2017 16:22:12 GMT
trehopr1 this is one of the specimens that I took of the board where I really wondered how that damaged happened. There are a few small spots on the hindwings without scales, it does look like having been eaten away somehow. I could not recall having seen that damage during spreading it, but then I was not sure if that damage happened during being on the spreading board or while being in the display box. Would you consider that book lice damage? It is definitely not from flying.
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Post by luehdorfia on Aug 20, 2017 16:25:14 GMT
Also on these burnets, I am not sure anymore for the two specimens on the left side, if these wings are just normal flight wear or if they have been damaged by book lice or anything else. As one can see the two on the right side are completely fine and fresh, but the two on the right look really old, and I am very sure that they were fresh when I caught them. Is there happening something in that box? What should I do to kill any pesticides immediately, PDB is already in there.
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Post by trehopr1 on Aug 21, 2017 3:28:33 GMT
Luehdorfia, regarding your question on the tupperware with the locking down handles; I would say they are pretty much airtight as the lids are held in place by the pressure exerted by the handles. You could always place an oversize book across the center of the lid (width-wise) so that it overhangs both edges if you have some doubt. Make sure you have 4-6 naphthalene moth balls inside and your specimens should dry out nicely. Don't put any PDB at all inside as it is very much stronger and reacts negatively with plastic. The fumes literally "warp" the plastic lids so as to "bow" or "bulge" the middle edges upward or outward so you than lose the lock-down effect. As to your beautiful arctiid moth I would say that it looks to me like the work of psocids. Psocids and dermestid larvae work in differing ways although the unfortunate outcome is the same --- eventually. Psocids do their dirty work usually while specimens are being dried out or "set" for the collection. Because psocids are so small and their food demands so minuscule any organic matter is attractive so it's only natural they first come in contact with the wings of specimens. They then it seems begin in earnest to "skeletonize" the wing membranes between the veins. Eventually, if their are enough of them and their work goes un-noticed much of the wings go missing and than the protein rich body is worked upon. Dermestid larvae are usually introduced to a collection much after the setting stage. Most commonly through newly added specimens which have not been given a good month's stay in a stiffly charged naphthalene container. Some people freeze new additions than take them out and freeze them again. I've never seen the need myself to go to those lengths; unless I of coarse knew I was acquiring something from an infested collection. Additionally, of coarse ill fitting lids or boxes will also allow dermesrid larvae entry as well. Unlike psocids, dermestid larvae seem to go for the largest protein source --- the body. They make entrance holes sometimes and yet other times they simply ravage all different parts of the body leaving behind a fine dust along with some larger bits and crumbs flaked off while feeding. The wings and antennae drop off and in time even these become fair game. Psocids tend to leave behind a much finer particulate "sooty" dust. I once saw a riker mount which had been at some time infested by psocids. The butterflies bodies were just fine sooty piles of dust and the wings were only dark sooty "impressions" of where wings once were. That riker must have just been crawling with guests for a long time.... As to your burnet moths; it looks to me like an oiling / greasing issue at hand. Those appear to be very greasy little moths as all in the photograph appear to have dark, greasy bodies. Could be that when the wings get sufficiently greased the scales and even the membranous tissue absorb it and the color appearance is altered. The specimen on the top left shows this best. The specimen below it on the bottom left is probably about 1/2 way there to looking just like the worst one. Give it a little more time... The 2 on the right look wonderful and may not ever be affected. Some collectors might suggest an acetone bath for those "greasers" which will leach out the body grease however, I remain concerned that acetone still affects the pigments in such a manner that the color (at least in leps) is never truely the same once applied. When it comes to greasy species (and there are only a few I have encountered) I simply weed out the "greasers" as I replace them with new fresh captures. Do it long enough and you eventually wind up with a small series of fine specimens that did not grease up. I've had good success with my Regal Moth specimens (Citheronia regalis) and my Cossid Moths. These are my humble opinions and I hope they aid you in saving your hard won treasures !
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Post by wollastoni on Aug 21, 2017 8:14:37 GMT
Agree with all what trehopr1 said, I would add that dermestids can also attack your specimens on the spreading board, especially if like me you let them on the board for one month. It happened to me. Adults in your home may lay eggs on them, and you will make "the fox enter the chicken house" if you don't freeze your specimens after spreading them. I always put all new specimens in the fridge (at the lowest possible temperature), for 5/7 days, before adding them to the collection.
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