This summer I did an internship for one month at an insect museum (sort of) called Le Naturoptère (here) presenting exhibitions about plants and insects to the public, located in the south of France, at Sérigan-du-Comtat (hometown of the famous Jean-Henri Fabre). I had the opportunity to take a look at the exhibitions and help in the gardens, but my real job was in the middle of the collection of butterflies!
Basically, the butterflies collection was a bit of a mess when I arrived because the staff had a billion of things to do and sorting this collection was not at the top of priorities. When I applied for my internship here and said that I had a keen interest in butterflies they were really glad and certain that I could be useful.
There were two boxes of butterflies (like above) and first I had mostly to isolate diurnal butterflies (aka rhopalocera) from nocturnal butterflies (aka heterocera or moth). For those who are not really accustomed to this order of insects, here are the main physical and behavioural differences between them so you will be sure, next time you see a butterfly, to say if it is a rhopalocera or a heterocera:
- thin antennae with a ball/club at the end;
- almost always very colourful;
- never fly during the night;
- when resting, the wings are maintained above the body, a bit like a sailing ship;
- thin antennae or feather-like antennae;
- often with dull colour on the top of the forewings to camouflage and the hindwings sometimes very bright to scare predators with an abrupt movement of the wings;
- mostly fly at night but some species fly also during the day or sunset;
- when resting, the wings are maintained againts the body, like a roof.
Agrius convolvuli, an example of heterocera/moth (with the roof-like wings and dull colours).
Satyrium esculi, an example of rhopalocera (we can see the ship-like wings and the clubs at the end of the antennae).
After I sorted heterocera and rhopalocera, I had to identifies the individuals of the collection that still were unknown, thanks to books and identification keys (I will not explain all the traits and characteristics here because it would really take too long) but I managed to organize the collection for it to be more accurate and complete.
My other job was to prepare specimens from private collections gifted to Le Naturoptère for scientific purpose (some specimens were more than 15 years old). There were more than one hundred of butterflies in boxes and envelopped in folded paper, dried but without the wings properly stretched. First I had to identify them properly, then to soften them thanks to hot steam (basically we have to keep the butterflies for 24 hours in a hermetic box with sand beforehand damped with hot water: the dried tissues of the insect’s body will absorb the water and the wings, antennae and legs will be malleable without breaking). Once the butterfly is softened, the body is pierced with a pin, like here:
Vanessa cardui, a rhopalocera
and placed in a little fissure practiced in a polystyrene plate, like here:
And then, with entomological forceps, plastic paper and pins, I carefully fixed the wings in the perfect place (you have to get an angle of circa 90° between the line of the body and the line formed by the separation between the forewing and the hindwing, like here:
Then I had to let them dry again for at least 48 hours before removing the pins an the plastic paper to place them in boxes with the collection.
My last activity was butterfly hunting: indeed the collection need to be completed with new species, and the species already owned but with old specimens need to get checked, to see if the species is still present in the area or not. To hunt butterflies, you need an insect net and some boxes in a bag to place your catches; then go outside and get ready to run!
Claire Hoarau (I apologise for the errors of translation, some terms might not be scientifically accurate).