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Post by africaone on Jan 27, 2012 7:56:24 GMT -8
Sometimes I have light brown lucanid (such as Homoderus or some light orange/brown species such Prosopocoilus "planeti", african ones) with the elytra or the thorax completely discolored becoming heavy brown, darkened.
In many cases this seem relied to moisture or decay.
My question is :
is it possible to come back to the original light color by any kind of method ?
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Post by zdenol123 on Jan 27, 2012 9:10:37 GMT -8
no....moisture is nasty thing even with Leps
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Post by simosg on Jan 27, 2012 11:13:45 GMT -8
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Post by lucanidae25 on Jan 27, 2012 12:07:15 GMT -8
It's the fat within the body and temperature, fat melts in room temperature and once the fat is in the cells; it's very hard to get it out. You can try acetones with only 2-3% water but keep changing the acetone untill it's clear, only then I will take it out and dry them or dry them very slowly in the fridge for 1-2 months.
You can only do so much to restore the colours in dried specimens, you really need to do it with live specimens and dry them yourself by using the same method above.
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Post by zdenol123 on Jan 27, 2012 12:37:58 GMT -8
changing colours by grease and moisture are two different things  . While grease can in most cases disappear by using acetone or "technical benzin", discoloration caused by moisture will never disappear...Thierry questioned moisture, so here I am... |
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Post by simosg on Jan 27, 2012 12:43:28 GMT -8
He said that it seemed, not that it is moisture, these are two different things too. So where you are?  Hannes |
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Post by africaone on Jan 27, 2012 13:58:00 GMT -8
i suppose it is moisture as it is for a non (or poorly) dessicated specimen that wait too long in a plastic bag.
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Post by simosg on Jan 27, 2012 14:21:54 GMT -8
I would cut one of the elytras and touch the body there. If it feels greasy, you know if grease or moisture is the reason.
Hannes
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Post by lucanidae25 on Jan 27, 2012 23:52:02 GMT -8
The cell structures between beetles and butterflies are totally different. Moisture dosen't cause any damage to colours in beetles, it's the bacteria and fat that causes the colour to change. I would start all over again by finding live specimens and dry them yourself, this will be the only way to make sure the colour dosen't change when dried. I dried all those specimens myself from live by using that acetone method. Colours havn't changed at all. Prosopocoilus fabricei takakuwai 82mm Odontolabis femoralis waterstradti 92mm Odontolabis femoralis femoralis 95mm Odontolabis versicolor 67mm Attachments:
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Post by africaone on Jan 28, 2012 1:44:55 GMT -8
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Post by lucanidae25 on Jan 28, 2012 1:54:15 GMT -8
Too bad just have to live with it!!! ;D  |
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Post by lucanidae25 on Jan 28, 2012 2:13:47 GMT -8
I spent the past 15 years trying to preserve the yellow with all my beetle specimens but it's only possible with live specimens. Especially with most the Buprestidae in Australia. Trust me I still havn't found a better way to preserve the yellow in beetles yet. Attachments:
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Post by africaone on Jan 28, 2012 2:51:54 GMT -8
yes i know this in africa i. e. for Pachnoda that lost their yellow with age that became orange or brownish (a nightmare for collection). In Butterfly i know it is irreversible bescause of the structure of wings with scales (that provides the color). I had yet the cases with cicindelid, clearly grease (a degreasing is always necessary with some genera) In my case of Homoderus it is more rely to an "accident" of moisture (? decay resulting). I had the idea of disassembling completely the specimen, put out any kind of tissues that are inside, wash inside and remounting it.  I don't know if someone yet used this technic that can be used of course for uncommon specimen.  |
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Post by lucanidae25 on Jan 28, 2012 3:14:12 GMT -8
Yes you can remove any tissues inside but how are you going to remove the grease within the elytra cells without using acetone?
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Post by africaone on Jan 28, 2012 3:24:37 GMT -8
washing implies tu use first a detergent and secondly if necessary acetone (or ether). i am looking for idea |
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. While grease can in most cases disappear by using acetone or "technical benzin", discoloration caused by moisture will never disappear...Thierry questioned moisture, so here I am...
I would like but how to find second male Homoderus taverniersi major (41 mm) A1 (except the color darkened) 
