Pseudoxycheila tarsalis – remounted

Pseudoxycheila tarsalis (Central American montane tiger beetle) | specimen ex. Costa Rica.

I tend to be a minimalist when it comes to mounting beetles. That is, I mount them so that they take up minimal space – legs tucked neatly and symmetrically against each side of the body and antennae laid straight alongside each elytron. This is important not only for space considerations (always a premium, but especially so in a private collection), but also to minimize the chances of accidental breakage when handling specimens. I must admit that beetles mounted in such manner don’t have quite the visual appeal of beetles mounted in a more relaxed, life-like position, but the ability to pack them tightly in my limited drawer space generally overrides whatever aesthetic desires I may have. Every now and then, however, I come across a specimen that just begs to be mounted life-like due to its striking appearance or impressive structures. Pseudoxycheila tarsalis (Central American montane tiger beetle), which I recently received as a gift from Henry Hespenheide, is one such species.

Remounting a dry, already-mounted beetle is a little trickier than mounting a fresh specimen. The beetle must first be relaxed, and even when relaxed well the beetle is never as pliable as when fresh. This makes it more difficult to get the legs and antennae into the desired position, and there is always a higher risk of breakage while trying to do so. Many different methods for relaxing beetles are available – some better than others, but for a one-off specimen I usually just soak it in very warm tap water. Generally 15-20 minutes will suffice, although large specimens may require more than this. Soaking has the added benefit of softening whatever debris might be caked onto the beetle so that it can be removed more easily. In this case, once the beetle was relaxed I used forceps to hold the specimen by the pin to keep it submerged in the water while “scrubbing” its upper surface with a camel-hair brush. Younger eyes might be able to do this unaided, but I find a binocular dissecting scope at low power to be quite helpful.

Once clean, I inserted the pin into a styrofoam block for positioning of the body parts. Since this specimen was to be posed in a life-like position, I didn’t insert the pin all the way, but rather left the body up off the styrofoam as it would be in life. Also, my favorite tiger beetle pose is slightly elevated on the front legs, so I inserted the pin at an angle to leave more space under the head than the abdomen. Then it was a matter of using brace pins to hold each body part in the desired position. I work from “sturdy” to “delicate” – i.e., the sturdiest body parts are placed in position first and the most delicate are done last, since positioning the sturdier parts causes tugging and pulling that could break the more delicate parts if they are already braced in position. This usually means bracing the body itself first, then then the legs, and lastly the antennae. Again, my eyes prefer to do this under a scope. While the antennae and tarsi can usually be positioned directly with the brace pins, sturdier body parts may need to be positioned and held in place with fine-tipped forceps in one hand while placing brace pins around them with the other hand. I also work “proximal to distal” with each part – i.e., positioning the part closest to the body first, followed by the more distal portions. There’s no way around it – this kind of work takes practice and patience, and even with all my years of experience I still managed to break off the distal four antennomeres from the left antenna (and failed in my attempt to glue them back on after drying). For this specimen, a total of 42 brace pins were used.

While fresh specimens may take several days (to a week or more for large specimens) to dry, relaxed specimens usually dry much more quickly – overnight was more than adequate for this specimen. Be careful when removing the brace pins! If you grab them too tightly as you pull them out of the styrofoam, you can end up “flicking” a leg or antenna and breaking it – better to grab the pin head loosely and lightly spin it back and forth as you pull up gently until the pin is free. Once all the brace pins are removed, pull up carefully on the main pin as well until you’re sure the tarsal claws aren’t grabbing the styrofoam – if they are, slide a pin or forceps underneath and gently unhook the claws before pulling the pin out any further. Replace the labels and voila – a much more aesthetically pleasing specimen! Is all this effort worth it? You be the judge. Below on the left is the photograph I showed previously for the specimen prior to cleaning and remounting, while on the right is the now clean and nicely mounted specimen.



With the beetle in its new life-like position (and scrambling for any chance to get some more practice with my new diffuser setup [photos coming soon, I promise!] as I slide into the depths of this Midwestern winter), I couldn’t resist the urge to take a few studio shots of the remounted beetle “on white.” While photographs of posed, dead beetles may not be to everyone’s liking, they do provide a chance to see detailed views of species that may not be otherwise available. The first photo above and the three below are some of my favorites from the session:

Photo Details: Canon 50D, Canon MT-24EX flash w/ DIY diffuser (photos 1, 7-8: Canon MP-E 65mm 1-5X macro lens, ISO 100, 1/250 sec, f/13; photos 2-6: Canon 100mm macro lens, ISO 100, 1/250 sec, f/16). Typical post-processing (levels, minor cropping, unsharp mask) with digital removal of pin heads and minor debris.

Copyright © Ted C. MacRae 2010

34 thoughts on “Pseudoxycheila tarsalis – remounted

  1. It’s a lot of work for a single specimen, but the results seem worth the effort.

    The third photo, with the beetle peering out from between the pins, is surreal – it would look great hanging on a wall or (gasp!) as t-shirt art. 🙂

  2. I envy you coleopterists and your ability to rehydrate and reposition your study organisms! Flies tend to go soggy, shrivel up and then ultimately explode in a blaze of legs and heads with the slightest touch… Fantastic staging job!

  3. Great! You are lucky that the eyes stayed dark, I find that a lot of dried Carabids (I’m playing with those right now) have white eyes that give them away as…aren’t we necrophiles??

    • I’m thinking white eyes would actually add to the surrealism of the photos – maybe I should look through the collection and see if I can find something like that.

      aren’t we necrophiles??

      Did I mention my skulls-n-bones collection?

  4. Very cool! That’s a lot of patience and dedication, and it pays off nicely. I can see why a specimen like this deserves more than the “stored” look. Perched like that really makes the difference, and the photos are spectacular.

  5. Oh, I am sooooooooo geeking out over this post. Fantastic, beautiful job. I am so happy to see someone else obsessively using gagillions of pins to get a prized specimen looking just so. Also very happy to get a close-up look at the marvelous schnozz that guy is sporting…it’s just wild!

    • Hi Geek – I can just see you bubbling with delight! (and thanks for the nice remarks)

      I’m still trying to figure out the purpose of that labrum – nobody I’ve asked has a clue. I do know that it’s not sexual, as I found an image of a mating pair on Flickr and it looks the same on both individuals. My “stabbing” hypothesis is actually starting to look pretty good. I took some much more highly magnified images and might do a follow up post if I learn anything more (or just as a plea for help!).

  6. Since I started out as a Lepidopterist, I started setting all of my Coleos in much the same way as you have discribed, only difference, I fold the antennae alongside the elytra and open the mandibles on Cicindelids.
    The legs are placed much closer to the body and each specimen does not take up much more space than if I had not pinned them thusly. Only problem is, I am about 3 years behind…..

    • Hi Richard – your method is very similar to my normal pinning method for tigers. I would’ve like to have opened the jaws on this specimen as well, but that is hard to do on previously dried specimens no matter how much you relax them (those mandibular adductors are some hefty muscles!).

      I mount cerambycids the same way, except the jaws are not opened, and the antennae – if they exceed the lenth of the body – are curled around behind and overlapping each other.

      Buprestids are easier, since they have such short legs and antennae – normally all I need to do is tuck the legs and antennae close without bracing. I do, however, routinely pull genitalia from all my buprestids while mounting, so that does add some time (ever try to yank the whacker of a Taphrocerus leaf miner?!).

      I am also about 3 years behind…

  7. In regards to that labrum, (you knew I couldn’t resist) … indulgentiam quaeso, … lest I suggest the obvious in that it has something to do with seizing and processing prey – only because of it’s location above the mandibles and wicked acuminate dentition. Nah, that’s too obvious and I don’t buy it. (Occam’s Razor, again?). Perhaps the labral setae are some type of sensory structures (sensilla) used to detect and identify airborne substances in the environment?

    But I am reminded, there can be a disparity between why a structure has evolved and what it ends up being ultimately used for …. food for thought, Mr. Wizard.

    Just another .02¢ ……

    Felices fiestas,

    • a bene placito. Actually, I think the sensory function makes the most sense – one would think of those setae might be vulnerable to breakage if its function were related to capturing or subduing prey. At any rate, it seems the function must be related to feeding just because of its location – it and the setae certainly contact a lot of food!

      I grow increasingly puzzled by the seeming lack of investigation on this structure!

      Boas festas para você também.

  8. Well Ted, you finally motivated me to remount a couple tigers I got from a very famous weevil specialist. He had pinned them like all his millions of weevils – stuck the pin through and let em dry. Legs all askew, head drooped down. The almost looked like weevils! I have been thinking of remounting them but didn’t want to break anything. When I read that Ted MacRae broke some stuff and couldn’t get it glued back, well, I decided to go ahead! I didn’t think there were many people who would be into remounting specimens from other collectors besides me.
    Mine came out good – not a great lifelike pose as you did with yours, but legs symmetrical and everything tucked. I even got the mandibles opened up (which I’ve been doing since I got your gift of a few tigers you pinned that way).
    I also did a couple BIG scarabs that were dry and unpinned. I soaked them for an hour and was able to do what I needed to do. Longer may have been advisable.
    I enjoy your posts. When I saw something about cleaning up tiger beetles I was excited that you were going to talk about hexane or some such solvent to do the real thing!
    Take care

    • Hi Paul — glad to know my post provided you with some motivation! While sometimes the act of processing might seem like tedium (and especially near the end of winter when the hundreds of specimens already processed didn’t make a big enough dent in the thousands still remaining!), it really is fun. I don’t remount specimens given to me by others that often – primarily cases like this or (more often) when the legs and antennae are just so extended and askew that I simply must do something about it.

  9. Hi Ted. I enjoyed reading about your pinning procedure and responses. I tend to place the legs right alongside the body, for the same reasons you noted. Several friends have chuckled when they see how many pins I use occasionally on a challenging specimen (e.g., longhorns). I purchased the long variety of stainless-steel quilting pins available at low cost from Walmart; just the right length and stiffness. You also mentioned cleaning older or dirty specimens by soaking in water and brushing. I use a biodegradable degreaser, available in a spray bottle from auto stores. On pinned specimens, I remove the labels, pin the specimen onto a piece of styrofoam, spray it, let stand wet for about 30 seconds, and then rinse gently under the tap. For an unpinned specimen, I spray it in a small ceramic or glass bowl, and rinse it there. Specimens that are decades old, sticky with grease and clinging dust, soil or cotton fibres, come sparkling clean, and look like they are freshly caught. A quick touch and swipe with a tissue removes any clinging material, and excess water. The specimen maintains its mounted position. I then make sure I replace the label before it can become mixed up with the next specimen. Unfortunately, this degreaser is of insufficient strength to dissolve old oils from the discolored elytra of tiger beetles; for this, some of the toxic solvents are required (and best used outdoors). This is why I leave recently captured tiger beetles in isopropyl alcohol (with some vinegar added to maintain suppleness) for at least a year, changing the fluid if it becomes stained with oils. The white maculations and colored parts then come out clean and bright.

    Like Paul, I often glue broken legs and antennae back on, generally using clear nail polish for smaller jobs. A friend gave me an adjustable gadget he made for holding specimens in position, using gravity for just the right angle. It consists of a metal base, a ball-and-socket middle section, and an upper bar on which is skewered a wine cork. Insect pins stick firmly into the cork, and it can be adjusted into any position. It works beautifully, holding the specimen until the glue dries. I hope other enthusiasts find these hints useful. Robert Wrigley

    • Great tips. I’d not heard about adding vinegar to ethanol to prevent brittling – I’ll have to try that. I use ethyl acetate as a degreasing agent for tiger beetles – not only because it is probably the most effective (and least harsh) of the organic solvents, but also because I can get whatever quantities I need from work as waste from our protein sequencing lab.


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