Introduction: Dry-Mounting a Scorpion

About: Proudly South African, Enthusiastic about the great outdoors, Natural Sciences, Photography, DIY, and all aspects of the natural world, with arachnids and reptiles being my absolute passion.

Okay, those of you who are familiar to my other Instructables will know what’s coming… A few VERY important things to remember before we take even a single step on the topic of dry-mounting a scorpion.

1. Scorpions are not toys. They are sentient animals just like us. They are extremely important to any eco-system in which they occur. NEVER collect a specimen unless you  have the following things;
A. A bloody good reason!! (Research, Environmental Education etc.)
B. All necessary legal documents. I live in South Africa and am required to possess a collection permit issued by “The Department of Environmental Conservation”, which is the authority here. I can’t give specifics on the details of another country’s’ systems, but be warned that illegal collection of fauna is a criminal offence, don’t take chances.
  C. An applicable knowledge on the scorpion species. Scorpions too have their scarce species. Make sure that your collection will not influence the environment.

2. Collect kindly. Never use anything more than what you absolutely need for your project.

3. Scorpions are not toys.

I will assume that the reader has spent some time reflecting on the above points. Aside from collecting, you can use this Instructable to mount a deceased pet scorpion which (hopefully) was bred in captivity. To summarize the preface, treat scorpions with respect, they’re older than you.

Extra note for scientists: I have avoided all manner of jargon in this Instructable, in particular, morphological names.  If you read the word “head” or “body” somewhere, please excuse me, but filling the Instructable up with “prosomas” and “mesosomas” will just annoy and confuse others. The specimen I used in this Instructable is Parabuthus raudus, a common species in the Kalahari Desert, South Africa.

Safety Warnings
I won’t spend much time on this, aside from the obvious dangers involved in working with potentially deadly animals; this procedure also uses needles and scalpels etc. Play it safe. Oh, and you’ll be working with acetone – don’t go drinking the stuff.
Nothing in this Instructable is inherently dangerous if you approach it with some good old common sense.

Step 1: Background (What Is Dry-mounting?)

Understanding dry-mounting is critical to this Instructable, therefore I've dedicated a whole step to explaining what it is.

Dry-mounting is a method of preserving a scorpion for displaying purposes such as framing or museum cabinets. 

The term “dry-mounted” refers to any specimens which are not preserved in Formalin or other liquid preservatives.

Normally, for scientific purposes, scorpions are always preserved in fluid. Dry mounting isn’t of much scientific value because it involves removing all the internal organs and essentially rendering the scorpion nothing more than a stuffed version of the real thing. Butterflies and moths are dry-mounted, but that nasty embryo you see on the mad scientist’s desk in horror films is wet-preserved.
Dry-mounting a scorpion is a longer procedure (than say with butterflies) as it involves gutting and ‘hollowing out’ the specimen to prevent rotting and also to keep the specimen’s shape. If you simply dried a scorpion out it’d shrink and warp something terrible.

With the background out of the way, let us continue!

Step 2: Requirements

A scorpion (obviously!)

A container of hot, soapy water

Pins – lots of them. I recommend that if you’re going to go buy pins, try getting different colours, it’ll make keeping track of the mounting procedure later.

Corn starch (you won’t need a lot)

Acetone – Try getting hold of pure acetone from your local pharmacy, nail varnish remover works too, but not as effectively as the medical grade stuff.

Cotton wool – avoid those cotton swab things because they are difficult to shred into small enough pieces, a simple roll of simple cotton wool works best.

Wood glue

Toilet paper

A torch – The torch will be very helpful for shining into the body cavity and all those hard-to-illuminate spots. Lighting is extremely important in dry-mounting.


Syringes – one large needle and one fine needle. I used two syringes; one is usually used for sedating a horse, the other for once-off insulin shots. You get the idea of large and fine needles!

A fine brush – not essential, but handy to have around.

A scalpel set.

Tweezers – I use two, it lets you work with one per hand. If you’re going to shop around for one, try looking in the beauty section of pharmacies etc. Look for the set with the finest teeth possible.

A glass of boiling water.

A mug of strong coffee – an absolute essential for any project!

I’m sure you can improvise a lot of the above items, but you’ll quickly find out for yourself which ones you can do without when we go through the step-by-step.

Step 3: Humane Killing and Relaxing

After collecting a scorpion, kill it. I strongly recommend NOT using a killing bottle for scorpions; they take days to die that way. A simple, cheap, humane and by far the most effective way of killing a scorpion is simply to put the scorpion in the freezer. Don’t worry, remember, scorpions are cold blooded, so a gradual temperature change will not cause it pain. Warm-blooded animals such as ourselves will feel colder and colder until a point of pain. Cold-blooded animals don’t feel that gradient at all, their bodies shut down at the same rate as the temperature drop.

Leave it in the freezer for a long time (overnight usually does the trick). Remove the now dead scorpion, thaw it out slowly in the sun and then, when it’s soft again, drop it into boiling water for about 30 seconds. This relaxes all the joints and will make manipulating the legs easier.

The 2 important things to emphasize here are A) Freeze the scorpion for long enough to make sure it’s properly dead.  B) Thaw it out properly and slowly before popping it into the boiling water, if you add it to the water while it’s still frozen, you’ll weaken the carapace as well as the joints. Think of what happens when you put an ice cold glass into hot water.

Step 4: Pinning Techniques

I'm going to briefly break away to fill you in on 3 basic pinning techniques.

They are referred to by different names by different people, but here I’ll call them Over-cross, Under-cross and Pillar pinning according to what the pins actually do to the specimen.

Pillar pinning is fairly straight-forward. It simply means putting one pin in straight down next to the body part. Like a row of pillars in a building. Pillar pinning is useful for building a “wall” on one side (or both sides) of the scorpion, preventing it from sliding around while you work on it. Think of Pillar pinning as building a fence of pins.

Over-cross pinning is where you use two pins inserted at angles OVER a body part, thereby holding it DOWN.

Under-cross pinning is where you also use two pins inserted at angles, however now they’re inserted UNDER the body part, thereby holding it UP.

Imagine an X formed by crossing two pins. If the body part, say a leg, is resting on the top of the X, it’s Under-cross pinning because the cross is below the leg. If the leg is being squashed down under the cross, it’s Over-cross pinning because the cross is above the leg. Moving on…

Step 5: First Incision

Now we have to align the soft scorpion for the first incision.

Pin the tail down using a series of over-cross pins.

Repeat these far enough down the tail at each joint to provide support. Next put a row of pins on the opposite side of where you’ll make the incision. This will allow you to use more force without warping the body.

Next you need to use a pin or two to get the legs out of the way, try pushing them forward, thus exposing as much of the soft side-skin of the scorpion as possible.
One pin inserted above and across the scorpion’s head will prevent it from flipping over.

Step 6: Gutting (Part 1)

Now we get to the nasty side of the job – the gutting… I’ll split the gutting into two sections – body and tail.

Take the ‘pointiest’ blade available in your scalpel set and poke a hole in the soft skin between the belly and back plates.

Start from the tail and slice the specimen open right up to just behind the leg joints. Be careful not to lob off a leg though. Take special care to slice the specimen open along the bottom of the skin, basically against the belly as opposed to along the back. This makes the next few steps easier because you won’t have to scoop the guts out over a flap of skin – trust me, that becomes annoying. Wash the scalpel blade off in the soapy water.

Once the first incision is complete, proceed to clean out all the insides from the body cavity.

Use the tweezers and cotton wool to do this, and dump the soiled bits of cotton wool on a piece of toilet paper. Don’t forget about scraping the insides from the head, which is equally important, although a lot more difficult because you’re working at an angle to the incision.

Scorpion entrails aren't very photogenic, so for sensitivity I've not included any photos of the actual gutting process.

Step 7: Gutting (Part 2)


Now that the body cavity is nice and clean, we need to clear the tail too.

Here I used the large syringe. Insert the syringe into the tail from inside the body cavity, scratch around carefully with the needle and suck out as much of the goo as possible. Push the needle into the second tail segment and repeat. Clean out segment by segment from the base to the sting.

A trick here is to put the torch right behind the tail, the light will shine through the partially translucent tail, and you can ‘see’ the needle inside it by concentrating on the light/shadow relationship. You’ll see what I mean.

What works well with thick-tailed scorpions (like the Parabuthus used in this Instructable) is a pipe cleaner. It’s optional, and I’ll mention the alternative method later. Take a pipe cleaner and VERY carefully insert it into the tail, again from the body cavity to the sting. Here we’ll need to pay extremely close attention because we already weakened the joints of the tail. If you’re too zealous with the pipe cleaner you’ll end up with a tailless scorpion. When you have managed to push the pipe cleaner as far up the tail as possible, then cut it off, leaving approx. 10-15mm of it behind in the body cavity. You can use the same trick with the torch that you used to watch the needle when we cleaned out the tail.

Step 8: Preparation for Filling

Now that the scorpion is gutted and cleaned, decant the acetone into a bottle capable of submerging the specimen. Pop the scorpion into the acetone bath and put a lid on the bottle. It’s important not to decant acetone until you need it. Acetone evaporates quickly. Oh, and it’s highly flammable so don’t light up!

It’s round about now that you must put your mug of coffee in the microwave – it’s ice cold.

On wood glue as a filling: Wood glue is an excellent filling for several reasons, it’s not expensive, works very well, moulds to the natural shape of the scorpion better than anything else and dries transparent, so small mistakes  here and there won’t show up.

However, for scorpions there’s a problem. It’s not the right consistency. You’ll need to mix it with some corn starch to make a dense paste, get it nice and thick. This paste will be the bulk filling of the scorpion which we’ll use for the body cavity. But what of the small bits like the legs, pincers and tail joints? Yip, standard wood glue is too thick for that job so you’ll need to dilute it a bit using the water you originally used to relax the scorpion. It’s too runny for the bulk filling and too firm for the fine filling. So, you’ll need to mix two separate amounts.

Once you've mixed the two fillings, go grab that mug of coffee and stretch your legs for ten minutes or so while the scorpion soaks in acetone.

Step 9: Filling

Fill the scorpion up with filling.

Yeah, you heard me, it’s that easy. Use the fine syringe to inject the diluted solution into the pincers etc. Once that’s done, use the past to fill up the body cavity.

(Remember back in Step 4 I mentioned an alternative to using a pipe cleaner in the tail? Well, fill the large syringe with NORMAL wood glue, not the diluted nor the thickened batch, and inject it into the tail, stick the needle into the tail up to the sting and then slowly fill the tail up from the sting back down to the body as you draw the needle out.)

Now you may ask why I dedicated a whole step to such a small task, to which I will simply chuckle knowingly. Be warned, it’s the most difficult part of the whole Instructable!

I took no photographs of the actual filling process simply because this part can go horribly south extremely quickly and you end up with a scorpion lost somewhere under all the wood glue… 
Attention to detail and patience are your best friends on this step.

Step 10: Pinning

Transfer the now filled scorpion onto a smaller card. Write the species and date of dry-mounting. This will let you keep track of how long it’s been drying.

I've sat in front of the laptop for about an hour trying to figure out a way of explaining the pinning process. Unfortunately there truly isn't a way of explaining it properly, but I’ll do my best.

Start off with pillar pinning the head down just behind the pincers.

Then, by inserting Over-cross pins, set the pincers in the desired positions.  Then progressively move down the body, pinning the legs in place, and finally use a series of Over-cross pins to secure the tail if you’re not planning to raise it or curl it. Museum specimens (pinned according the scientific norm) are ALWAYS pinned with the tail lying straight and flat behind the body, not raised as I've done here or curled to the side as you’ll often find in framed specimens.

This is just about all I can say about pinning. On first glance the finished product may resemble an uncoordinated mess of pins, but if you follow the pins down to where they actually interact with the scorpion itself, you’ll notice that they all play an important role. Here I will add a few general tips about pinning the scorpion; I sincerely hope it makes this step easier for the reader.

1. Try and follow the natural stance of the scorpion, pay particular attention to the legs. I recommend even taking a photo of the scorpion before you collect it, this may provide a reference to how the scorpion holds its body naturally. A well pinned dry-mounted scorpion should look as if it’s going to get up and walk off, try replicating that as closely as possible. (Like with my specimen you’ll notice the hind legs are pinned in a raised position, not flat to the ground.)

2. Symmetry is everything. When you pin different parts of the scorpion, pin it in a left-to-right pattern. Basically once you have pinned the left pincer, don’t move on to the legs until the right pincer has been pinned. Equally, once you’ve pinned the left front leg, pin the right front leg before moving to the second left leg and so on.

3. At no point do you drive a pin through the body of the scorpion, always set the body (and all the other bits) by pinning on either side. Take care that you don’t accidentally stick a pin through a leg or anything like that.

4. Follow your head. There really is not set-in-stone method to pinning a scorpion. Basically if it looks right, great. Use the Pillar, Over-cross and Under-cross methods in most cases, but an occasional single pin here and there can also make the world of difference. Notice on my specimen how I added a single pin in-between the gap of each pincer? That pin holds the pincer open, which is how you’d find the scorpion in the wild. Such details improve the specimen greatly. This ties in with my next point:

5. Pay great attention to detail.

Well, that’s that hey. Now you leave your specimen to dry out completely. Usually a week or two will do the trick, but rather leave it pinned for too long that not long enough. The specimen should NOT give off any smell what-so-ever.  If it smells funny you didn't clean it out properly. At the very worse you might get a whiff of acetone off it for an hour or two after pinning, but that’s all. 

Another hint is to use some of the diluted glue from Step 6 to “tack” the scorpion’s joints – notice on the tail of my specimen’s tail joints. The diluted glue will dry transparent, while at the same time providing a bit more reinforcement to the joints.

Once the specimen has dried out properly after a week or two, carefully remove the pins one-by-one. Take care when working around the legs.

Your scorpion is now ready to display!