A new heterodont pterosaur

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The skull of Raeticodactylus filisurensis. From Stecher 2008.


ResearchBlogging.orgOn April first I wrote about heterdonty in lizards, dinosaurs, and crocodylians, but it was no April Fool's Day joke; mammals aren't the only animals that have differently-shaped teeth throughout their jaws. I should have waited just a little bit longer to write the post, though, because a new genus of Upper Triassic pterosaur from Switzerland named Raeticodactylus filisurensis has just been announced in the Swiss Journal of Geosciences.

Raeticodactylus is certainly a strange creature. It has heterodont teeth, a crest, and shows no close relationship to the only other crested Triassic pterosaur known. The teeth in the front of the jaw are longer and cone-shaped while those towards the back of the jaw (separated from the front ones by a diastema) have multiple cusps on them, suggesting that it was able to both grab and cut/crush its prey. Being that it was discovered in marine sediments, it may have dined on fish (although whether it was a skim-feeder or not in life is dubious.) According to the section of the paper comparing Raeticodactylus to other pterosaurs, though, it's apparent that it was not the only one to have heterodont dentition. Austriadactylus cristatus, Eudimorphodon cromptonellus, Eudimorphodon ranzii, and Eudimorphodon rosenfeldi are all listed as being heterodont, too.

I have to admit that don't know as much about pterosaurs as I probably should, though, and there's little more I can say with confidence about this fossil. The paper is available online here, however, and I hope other bloggers with more expertise than I have will pick up this research and be better able to summarize it.

Update: Other bloggers have provided better summaries than I, and can be found at the following locations;

DinoBase Forum (Dave Hone) - "The pterosaur - Raeticodactylus filisurensis"
When Pigs Fly Returns - "Raeticodactlyus = Fishing Eagle?"
and
Microecos - "Enigmatic Triassic Hellasaur Thursday... wait, what day is it?"

References;

Stecher, R. (2008). A new Triassic pterosaur from Switzerland (Central Austroalpine, Grisons), Raeticodactylus filisurensis gen. et sp. nov.. Swiss Journal of Geosciences DOI: 10.1007/s00015-008-1252-6

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Cool! Another strange addition to the end Triassic radiation of pterosaurs. Do you have the paper, and could a reader request a copy?

Regardless, thanks for the news.

By Adam Pritchard (not verified) on 08 Apr 2008 #permalink

jck; The bottom reconstruction shows the extent of the crest (it did not extend all the way back).

It's a great paper, although the authors imply a close relationship between this new taxon and the Eudimorphodon group (it's never explicitly stated). I was most surprised by the strongly parasagittal femur. This suggests that a parasagittal femur is basal for the Pterosauria and that later members who developed a sprawling gait did so because of transformations to the pelvic girdle due to the limitations of the flight aparatus.

Love that horn. I also love big "chin" on the lower jaw. The proportions of this new critter are much different than other Triassic pterosaurs, but I wish some body parts (as opposed to limb parts) had been found.

I'll definately be blogging about Raeticodactylus later this week!

"Being that it was discovered in marine sediments, it most likely dined on fish"

- Well, there's lots of other things in the marine realm to dine on besides fish. Stecher accuses the thing of being a durophage and there are lots of molluscs in the Kossen formation for example, I don't know about crustaceans...armored fish?

But of course depositional environment does not necessarily reflect foraging environment. This is especially so with flying animals--I don't think the Green River bats were eating Knightia.

Superficially the resemblance to Caviramus is striking. It's tempting to make an ontogenetic series out of them...though I know that's an unpopular move on your blog these days : )

The crest makes me yawn, but that angled retroarticular process and quinticupsid (!!!) teeth now that's effing rad. Okay, I shut up now.

In a bit of self plugging, I have a couple of huge articels in the go on this for my blog. I did all the language stuff for Rico on the paper and have looked over extensive unpublishged photos of it and discuassed it with him. Give me a day or two...

By Dvae Hone (not verified) on 08 Apr 2008 #permalink