Monthly Archives: May 2013

The Making of Imaginary Pterosaurs


Click on the image above to download the PDF of my presentation at Rio Ptero 2013 about pterosaur reconstructions. Warning: it’s a big 186 MB file. You might prefer to right click and use “Save as…”. Soon I will also publish it in Scribd for online viewing.


Filed under News and Exhibits

Imaginary pterosaurs in Rio

The Imaginary Pterosaurs have just returned from a trip to Rio, where they were on display during the Rio Ptero 2013: International Symposium on Pterosaurs, at the National Museum of the Federal University of Rio de Janeiro. It was my first pterosaur symposium and also where I had the opportunity to examine real pterosaur fossils for the first time (so far, I had only seen photos). I also had the opportunity to meet many of the researchers whose articles and books have inspired me, and which I have used as sources to make and improve my models. Here are some photos and a brief non-technical overview of the event.

I didn’t only take my art to the Rio symposium. I also acted as a curator and displayed the pterosaur art of Sergey Krasovskiy. I printed some large ones which you can see here on the box where most of the pterosaurs are safely packed.


This pterosaur box was lost for 24 hours in the airport during my last trip. It was hard to find since it looked just like a plain box. This time I decided to paint something on it. In case they lose it, it shouldn’t be very hard to locate. Almost all the pterosaurs are in these boxes. There are four skulls and skeletons in the big box, the Anhanguera is in that smaller one (which I carry as hand luggage) and I packed the Tupandactylus with my other checked luggage (I had to slice it it three parts, though).


After spending some 1000 reais (~500 US dollars) to take my pterosaurs to the Dinosaur symposium in Minas, last month, I had to spend a similar amount to register, buy tickets and other expenses for the Rio conference. I haven’t worked much in the field where most of my income comes from (computer programming) since I have dedicated a lot of time to this art. As a result I am currently low on funds, so I decided to make some T-shirts and other art that I could sell at the symposium. These are the T-shirts I planned:


Way too expensive. I had to make them black and white, otherwise they would cost too much and nobody would buy them. I made 30. Sold 20, which was just enough to cover their cost (I gave away 4 so I still have 5 left, besides the one I kept). I made some acrylic painted paper pterosaurs which I sold half and gave away the others. I also sold some of the prints, but it wasn’t enough to cover the printing costs. So my business strategy didn’t work out very well, but it was worth it (I’m still selling the 5 shirts :)). Many thanks to everyone who bought these products!


By the way, the paper craft plans for those pterosaurs will be published here in PDF as soon as I have time to finish them.

My pterosaur skulls and paper models were on display on a table and the Tupuxuara was assembled in flight position (for the first time). I would like to thank Christopher Bennett, Darren Naish, Nathan Carroll, Ashley Poust, David Unwin and Felipe Pinheiro for pointing out inaccuracies in the assembly, which I was able to fix.

Below: me and Felipe Pinheiro while I was assembling the Tupuxuara (photo by Samuel Lima).


Here is my Tupuxuara leonardii based on photos of the Iwaki specimen (ICMF 1502).


My Tupandactylus skull (based on the holotype and other sources). Photo by Paulo Marcio Esper.


Anhanguera, Dsungaripterus, and the undescribed thalassodromid that was for sale at PaleoDirect. Photo by Paulo Marcio Esper.


Here are some pictures of the paleoart exhibition. Besides my sculptures and Sergey Krasovskiy’s pictures, there were also some fantastic sculptures, drawings and paintings by Maurilio Oliveira. This is his Thalassodromeus (photo by Paulo Marcio Esper):


And this is one that was on display (which I found in his Facebook page).


Maurilio was also drawing pterosaurs during the event (photo by Samuel Lima):


You can see that I hung the skeleton with fishing line. It now weighs 950 grams (it gets lighter every day).


I didn’t assemble the Guidraco skeleton, as you can see, but I spread its bones on the table.



Here is view showing most of the exhibit. Sergey’s paintings are on the left and Maurilio’s are on the right.


On the last day there were also two paintings by Paulo Márcio Esper (his first pterosaur drawings). I don’t have pictures from his exhibit, but I found this one in his Facebook page:


I didn’t spend much time near my art since I was very interested in attending all the sessions. It was a small event. There were about 50 people. I still have a lot to learn before I can participate in many of the discussions there, but it was very instructive and it was definitely worth all the effort to be there.

Here are some pictures. This is Christopher Bennett discussing about the structure of the pterosaur wing (the Rhanphorincus Zittel wing).


David Unwin, the author of one of my favorite books on pterosaurs.


And Darren Naish, whom I knew previously from his blog Tetrapod Zoology.


Here is a news broadcast on local TV (in Portuguese) that was recorded a couple of hours before the beginning of the event (I hadn’t even finished assembling the Tupuxuara).

On the first night we had the opportunity to visit the pterosaurs and dinosaurs at the National Museum, where the opening cocktail would happen (the symposium was actually in the auditorium of another building, at the botanical garden of the museum). The museum is situated in the building below which was the residence of the royal family of Portugal from 1801 to 1821. It is situated in the middle of a beautiful park called Quinta da Boa Vista.


Here is a classic scene from the Cretaceous of Brazil: an Irritator attacking an Anhanguera. This is actually based on fossil evidence: a tooth from this dinosaur was found in an anhanguerid cervical vertebra.


This is a view of the dinosaur hall. Look up! There is a giant pterosaur (Tropeognathus mesembrinus) above you.


A very nice cast of a Tupandactylus imperator.


The holotype of the Tupandactylus is not at the National Museum, but in the Museum of Earth Sciences where we had the second after meeting cocktail.


When you enter the museum there is a large picture of a Thalassodromeus sethi pterosaur skimming for fish painted on the floor (by Maurilio Oliveira).



The museum is fascinating. Unfortunately my camera batteries died, and so did my phone and I was unable to get a picture of the Tupandactylus. (But I caught this dinosaur sleeping in its egg just before the batteries died.)


Unfortunately some presentations were cancelled since the speakers didn’t make it to Rio. But then I, who was not scheduled to speak, was offered the opportunity to do so. Many thanks to the organizers of the event for this opportunity to share my experiences in making my pterosaur skeleton sculptures. I have published the presentation here before, but I updated it recently. I will later publish it here for whoever wants to download it. Photo below by Samuel Lima.


The event lasted three days. On the last day we had the celebration dinner in Urca with a fantastic view of the Botafogo bay and the Pão de Açucar. Pictures? Nope. I forgot the camera this time 😦

On Sunday some people went on a city tour, and others spent the day at the museum examining fossils. Since I had never touched pterosaur fossils before, it was my opportunity. There were several holotypes to see, including Thalassodromeus sethi (pictures below), Cearadactylus atrox, Tapejara wellnhoferi, and others. Here are Darren Naish and David Unwin examining the Thalassodromeus.



I made a lot of pictures of the Anhanguera blittersdorfi skull. It might be one of my next projects.


After that I packed everything and free at last enjoyed an incredible walking tour around Ipanema, Lapa and the old centre at night, with Nathan Carroll and Ashley Poust (from the US), hosted by Lilian Cruz (from the National Museum).

And that’s it. It was a great week. Thanks to Alexander Kellner, Juliana Sayão, Taissa Rodrigues, Fabiana Costa, Maurilio Oliveira, João Carlos Ferreira and all the others who organized and contributed to the success of the event. Special thanks to Elaine Machado, Lilian Cruz and Kamila Bandeira for helping me out with the exhibition, and to Samuel Lima and Paulo Marcio Esper for the photos. Please forgive me if I forgot anyone.

On Monday some flew north to the field trip at the Araripe plateau, and I flew back to São Paulo with my pterosaurs.



Filed under News and Exhibits

Imaginary pterosaur #6: an unknown thalassodromid/tapejarid

neck 2
“Hey Tupuxuara, this is your unnamed cousin! Can you lend me your neck for a minute? I need to take a picture!”

This reconstruction was based on photos that were on display at a website that sells fossils (Paleo Direct). It wasn’t studied, it has no formal identification and no name. Some paleontologists believe it has been adulterated, and one of them believes it’s fake. I think it might  have been damaged, even altered, but not significantly. Well, if it really is fake, then I have made a reconstruction of an inexistent imaginary pterosaur… but hey! That is totally consistent with the project of this blog 🙂

I made this one very fast. First because I didn’t have to do much speculative research. I used the source photos, and based the unknown parts on Thalassodromeus and Tupuxuara. Second, because I’m getting better at this. It still takes three days because I have to wait for the glue to dry before continuing. So I might work for 20 minutes, and wait an hour or two before working again for another 20 minutes. When I work in different parts of the skeleton I can be more productive. In this case, I worked simultaneously on the skull and on the mandible and was able to speed things up a bit. It took me three hours to make the first foam “3D sketch” of the skull. And then another three hours for the mandible and palate. Then I spent eight hours adding the little details (which make all the difference). And finally two more hours to finish it with resin and coffee.

The material I used was:

  • One 100 x 60 x 0.3 cm sheet of XPS foam
  • Scraps of XPS foam of other densities and widths for details
  • 50g of foam glue (PVA – Polyvinyl acetate diluted in alcohol)
  • 100 ml of acrylic resin (modelling paste)
  • Coffee (for stains)

And these are the final dimensions and weight:

  • Length (beak to rear crest): 63 cm
  • Width (jaw hinge): 12 cm
  • Height without mandible: 26 cm
  • Height with mandible: 30 cm
  • Mandible width: 10 cm
  • Mandible length: 47 cm
  • Total weight: 105 grams

The only dimensions I obtained from the fossil photograph were height and length (based on the length informed by the seller, since the photos had no scale information). The width was estimated using Thalassodromeus and Tupuxuara as referenes.

The skull should get lighter during the next couple of weeks, when the resins and glues dry completely (when I first weighed Tupuxuara’s skull it weighed 290 grams; One month later it weighed 220 grams).

Here are photos of the finished skull.

Side views



Dorsal view


Mandible (dorsal view)


Mandible and skull

side palate



With a neck

(Using Tupuxuara’s cervicals)

neck 1

Crest details

crest 4

crest 2

crest 1

crest 3

crest 5

Occipital views


jaw hinge

Intra-cranial views

inside 1

inside 2

Right orbit details


Palate details

palate 2

palate 3


Family photos

This is pterosaur #6 compared with pterosaur #5 (Tupuxuara leonardii).

with tupuxuara

And here is the whole Imaginary Pterosaur family so far: Guidraco (#1), Tupandactylus (#3), Anhanguera (#2), Dsungaripterus (#4), Tupuxuara (#5) and pterosaur #6.

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List of posts about pterosaur #6

Here is a list of all the posts related to the construction of this skull. Many of the techniques I used here I have detailed before in posts about the other skulls.

  1. A new species from the Cretaceous of Brazil
  2. Pterosaur #6: the palate and the mandible
  3. Pterosaur #6: details, details
  4. Imaginary pterosaur #6: an unknown thalassodromid/tapejarid (this post).

Sources and Acknowledgements

The only fossil source I used to make this model were four photos that were recently available at the Paleo Direct site (one of them I posted here). They aren’t there anymore. Besides that I had help from the paleontologist Hebert Bruno Campos, from whom I obtained information on the palate, mandible and skull details of the Thalassodromeus, used to fill the gaps.

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Pterosaur #6: details, details

The small little details take up more than half of the time, but they are what make the skull look authentic. I added several details in the skull, behind it, on the orbits, crests and palate. I used several techniques: creasing, burning, heating, melting with PVC glue, scratching, removing foam, adding foam, adding acrylic resin and staining with coffee. Here are some pictures.

The orbits stand out laterally. By folding and stretching the foam I was able to shape them well but one more layer of foam is needed to make it stand out as it should. This is the orbit before adding details.

orbit details 1

And after.

orbit details 2

Most of the crest details are obtained by heating the foam with a lighter. Not burn. The lighter has to move from the inside to the outside. The first time will barely cause any effect, but the foam will heat a bit. The second time it will shrink, and after that it will produce bubbles which make the effect you can see below. If you go beyond that it may melt or catch fire. If you previously mark anything with a pencil you won’t be able to erase it later. You can draw veins with glue, wax, paint, and when you heat the foam, that part will be protected so you can control which parts will stand out and which parts will sink in the crest.


After the fire I also added thin strips of foam for the crest details around the orbit.

crest details

I don’t know what the inside of the head looks like. Most of the time it’s not visible. After some research I did something like this for the Tupuxuara, and I decided to repeat it here.

inner skull details

This is the palate almost done. I’m working on the posterior part of the skull.

posterior skull details 1

Here I added some details around the occipital bones.

posterior skull details 2

Finally, I coat the foam with a layer of flexible and matte acrylic resin. It not only strengthens the foam making it less liable to crack, but it also protects it from corrosive chemicals which could melt the foam and reduces significantly its flammability. The foam becomes harder on the outside, but the resin is somewhat flexible, so it’s easier to rip a piece off than to crack it. I could also add a layer of epoxi resin to make it even more resistent and hard, but I usually prefer not to since that significantly increases the weight, changes the texture and leaves the skull with a shiny surface. I usually only add epoxi to the fragile parts (beak tips, and thin parts that stand out) and to surfaces which will be in contact (the jaw hinges). After the epoxi is dry, I scratch it a bit and add acrylic resin over it.


After the resin is dry, I make a cup of coffee and save the used powder to stain the skeleton. I usually sand the smooth parts before doing that (mandible, orbits, etc.) By adding powder multiple times, and rubbing firmly it with fingers, a toothbrush or lightly with a paintbrush, I can achieve different effects and make some parts darker than the others.


In the next post I will publish the final results.

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Pterosaur #6: the palate and the mandible

For the mandible I started with the side view picture from the original fossil, but it was partially covered and had no other angles, so I scaled the mandible of a Thalassodromeus to use as a reference.

2013-05-15 13.11.32

I cut the two halves, folded and molded a bit and then pasted them together. I also cut out the dorsal side.

2013-05-15 14.07.44

After fitting all the parts, I filled the open ones with smaller bits of foam.

2013-05-15 14.18.08

For the palate I used Tupuxuara as a reference, but also referred to the Thalassodromeus for the layout of the bones. I cut a flat palate + occipital bone from a sheet of foam, cut out the empty parts and folded it.

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I shaped the palate convexly to match the original fossil.

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And attached it in place.

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Pins aren’t enough to hold it in place while drying.

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The occipital bones were attached after the palate was dry.

2013-05-15 01.27.00

So now I have a rough 3D sketch of the skull. I used a lighter to melt away part of the foam and make an interesting spongy effect on the crest.

2013-05-15 11.25.33

I also used fire to shape the palate, the jaw hinge and the throat after the occipital bones were in place.

2013-05-16 11.33.24

It’s practically finished. Now we need to add the details, which takes up most of the time.

2013-05-16 09.10.27

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A new species from the Cretaceous of Brazil

In a few days I will travel with my pterosaurs to the 3rd International Symposium on Pterosaurs: Rio Ptero 2013. I decided to take some time and add one more skull to the family.

This fossil was on sale at Paleodirect but not anymore. Either it was sold or (hopefully) acquired by a paleontological institution. I am making the skull out of foam using only the few photos that were available online (unfortunately the link is now broken). This is the main photo.

Screen Shot 2013-05-14 at 3.38.00 PM

It consists of a full skull and mandible, and the first cervical vertebra and is about 60cm long. Compare it to the Tupuxuara (a Thalassodromid). If you look at the position of the orbit, the two crests, the mandible, you might say it’s a Thalassodromid. But if you look at the beak and the size of the head it might remind you of a tapejarid, such as Ingridia navigans, for example. It’s somewhere in between these two genera and it’s evidence that Thalassodromids and Tapejarids may be somehow related.

Since the rear part of the skull is very similar to the Tupuxuara, I will use the Tupuxuara as a model for the palate and the bones behind and inside the head.

I started out as usual, transferring the outlines of the fossil to a sheet of foam, scaled to the fossil’s dimensions. Since the heads of these pterosaurs are almost flat, I don’t have to compensate much of what I lose due to the 2D projection (I just compensate a bit around the orbits and below the mandible). Lost details I can always add later, with extra bits of foam.

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This is the final sketch.

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You can now finally see what it looks with the beak open.

2013-05-14 12.55.27

After cutting out the two halves I spent some time pressing, folding, and shaping the foam to make it three-dimensional, and cutting out some details. I don’t really know what that cavity near the beak tip is. I also compensated the shape of the nasoantorbital fenestra which seems to have some details still hidden behind the rock (the lacrimal fossa, perhaps).

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Then I glued the two halves together. Tomorrow I will continue and add intra-cranial details such as the palate, occipital bone and cavities.

2013-05-14 15.02.34


Filed under Pterosaur #6: Caupedactylus ybaka