THE PRESERVING OF INSECTS.
Unprepared specimens of insects can be stored in three ways :
a. in relaxed condition
b. in full dry condition
c. in preserved relaxed condition.
a. STORAGE IN RELAXED CONDITION. [ maximum storage 14 months ]
If we use for killing ethyl acetate (or amyl acetate) added to sawdust, tissue paper or foam rubber, we can use for storage the same jar. After collection, add a little more killing solution (to compensate for evaporation during collection) and seal with an airtight plug (the cork is best).
The tissue papers, sawdust (or foam rubber) must be d a m p ,NOT MOIST or WET.
In this manner the specimens can be stored for up to 14 months without any damage. After this time specimens decompose. Antenna and tarsae appendages fall off first in moist cases. This manner protect specimens mostly against pests but not against mould. Therefore it is good to add some anti-mould solution.
b. STORAGE IN FULLY DRY CONDITIONS.
The material must be stored in a dry and ventilated place.
Transfer the specimens from the killing jar to clean sawdust ( the best size of sawdust is that which has been sifted through sieve with mesh size 10 x 10 mm but unable to be sifted through 2 x 2 mm). Add to the sawdust anti-mould solution (creosote, thymol crystals etc.) and an anti-pest preparation ( paradichlorbenzene, nitrobenzene ; naphtalene alone is not effective ), and repeat when necessary.
Specimens can also be stored in paper tubes, boxes, butterfly papers etc. For beetles (in particular) one of the best methods of dry storage is the following manner :
Cut out a piece of cardboard approximately 40 x 50 mm, (depending on the size of the insects - must be least 20 mm bigger in the area than the beetle(s). Place a layer of tissue paper (0.7-l mm thick) on top of the cardboard and add a few drops (or crystals) of anti-mould and anti-pest preparations to the tissue paper and place the beetle(s) on top and then cover with cellophane. Staple the cellophane to the cardboard and tissue paper along its border. (sees Fig.1.)
Write important data on the back side of the cardboard.
³ ³1 1 = the cardboard
[ ³ 2 = the tissue paper
/ ³ 3 = the cellophane
³ ³ [ = staples
3³ ³ O = beetles
CAUTION : Before removing beetle(s), first soak the card board in moisturing solution until the cellophane relaxed.
c. STORAGE IN PRESERVED RELAXED CONDITION.
(sensu Pulpan & Winkler).
The following method is one of the best for preserving relaxed specimens. Not only does this method preserve but it also cleans and gets rid of fats within the specimens, as well as giving good protection against moulds and pests.
Samples can be stored for more than l5 YEARS WITHOUT ANY CHANGE and can be prepared immediately after they are taken out from the preserving solution.
If used CORRECTLY, this method yields the best results.
METHOD : In order to kill the insects the sawdust (or foam rubber) must be MOISTENED ( but NOT TOO DAMP and NOT TOO WET ), with ethyl acetate. The insects are kept in an airtight container with moistened sawdust for 10 - 14 days without if possible, any further addition of ethyl acetate (only after collecting do we add more acetate to compensate for evaporation during collection).
After 10 - 14 days take the insects out of killing jar and place in Petri dish lined with filtration (or tissue) paper that has been soaked in "wavide" solution. (= 4 parts of water, 1 part white vinegar and 1 drop of detergent for every 20 ml solution.). Leave specimens in the closed Petri dish for 24 - 48 hours
( protect against drying !).
NOTE : Specimens which are already in a full relaxed condition after removal from killing jar must also be placed in a Petri dish for the same time.
After this time period remove the specimens from the Petri dish and place them on clean filtration (or tissue) paper, lightly dry their surface and immediately transfer them to jar conp6np6 taining c a r b o n t e t r a c h l o r i d e = CCl4 or b e n z i n e (as a medical pure benzine NOT GASOLINE). [ Those chemicals are dangerous, and at least the former has been banned for us in the U.S. please be carefull]
Label the jar with appropriate identification data and store indefinitely.
Specimens stored using this method remain clean, and fat free and their colors are enhanced due to earlier exposure to ethyl acetate.
Before fixing the specimens for display remove the insects from labeled jar and transfer then to a clean jar containing carbon tetrachloride (or benzine) and wash them to remove any remain fats and sediments.
Immediately fix the specimens in a display posture once they are removed from preserving solutions. Work INDIVIDUALLY, do not forget that specimens dry out very quickly once they are removed from the preserving solution .
If the specimens are fixed in an incorrect posture and have become dry and hard do not return them back to tetrachloride (or benzine). They MUST be returned to their soft and relaxed condition using of the correct moisturing methods.
Note : The above method using carbon tetrachloride (or benzine) were developed for beetles but can be used successfully on other insects as well.
CAUTION : NEVER RETURN DRY, HARD SPECIMENS TO TETRACHLORIDE OR
BENZINE YOU MUST RELAX THEM FIRST !
Tetrachloride could be treated carefully.
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Last modified on Tuesday, 12 November 2019