Specimen recuration or ‘how to fix a broken beetle’

We recently had an enquiry asking for advice on how to fix an entomological display specimen and after some discussion, it was decided that it would be best if the specimen be bought into the collection to be professionally repaired. The specimen was that of a scarab beetle, Chalcosoma atlas (Rhinoceros or Atlas beetle) a relatively large species found in South-east Asia. 
As specimen repair is something that we have to undertake on almost a daily basis and one of the seemingly more baffling aspects of our job (not many people get to say that they glue insects back together for a living after all) we thought it might be interesting to show something of the hands on side of our work. We undertake repairs on a whole variety of dried insects and arachnids, many of which are of historical value. Damage can occur either through pest or mechanical action or from initial poor specimen preparation.

The first image shows the scarab as it was when it arrived. Along with the obvious destruction, there was also severe pest damage, caused by the Flour beetle, Tribolium castaneum. This meant that before any restoration could be done, the specimen needed to be frozen to kill any remaining pests. It was bagged up and frozen at -30°C for six days. Once it was un-bagged and removed from the frame, it was vacuumed thoroughly to remove all the dust and debris caused by the pests. A paint brush was used to gently clean the specimen. 

Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Pest damage has led to this specimen disarticulating in its display case
The restoration had to be done in-situ as the specimen was glued to the glass to with some heavy duty glue and could not be removed. 
The first stage of repair was to reattach the legs; there were two missing, one beneath the right wing and the right front leg, which was also missing part of its claw (these areas are highlighted in red on the image below). The glue we use to fix insects is of conservation grade and water-soluble; this means that it will not have a detrimental effect on the specimen; it does take longer to dry, but has the benefit of drying clear.
Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Areas ringed in red show where repairs have been undertaken on the specimens legs
Once the legs were secure, the head was attached. Foam was required to form a ledge to raise the head to the correct angle; pins were then used to hold it in place for the two hours it took for the glue to dry. The image below, top shows the positioning required. The final stage was the re-attachment of the elytra (front wings). A similar method was used as for the head, but this time towers of white tack were also needed along with the pins to form full support (below, bottom); because the area of attachment was so small, the weight of the elytra needed to be completely supported while the glue dried.
Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Head propped on plastazote block to obtain correct angle
Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
Wings held in posistion with stacks of white tack


Once the glue had dried clear in all the areas, the specimen was finished and ready to be reframed, as seen below- or not as the case may be as the aim of all repair is to do it in such a way that it should be almost impossible to tell that it has been fixed.
Insect, Coleoptera, Scarabaeidae, Chalcosome atlas, HEC, OUMNH, specimen repair
The final appearance of the specimen once it had been repaired

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