Say farewell to Oxalaia and Sigilmassasaurus.

[suspsy]

There is only Spinosaurus.
https://www.sciencedirect.com/science/article/pii/S0195667120302068?fbclid=IwAR1Q6HmgZ6nGYzCUuFOq0OOuiMtX--7bZwWO2dVrsQsWnoZUdC-sqNbddYE

Good thing neither of those genera ever got a toy!

[Ravonium]

Ibrahim really has been on a roll this past month.

[Shonisaurus]

It is good news on the one hand, a mystery of paleontology is revealed more, but on the other it is still negative in the sense that those dinosaurs do not exist and I suppose that the same will happen to other dinosaurs such as pachycephalosaurus / dracorex and stygmilocho may be the same dinosaur and unfortunately figures of those three dinosaurs of the Marginocephalia Pachycephalosaurida family have been made when those dinosaurs belong to the same species and are mere variants of antlers. In any case, it has been avoided that the oxalaia and sigilmassaurus are represented in figure form.

[suspsy]

The idea that Spinosaurus was in South America as well as Africa shouldn't come as a shock given that Sarcosuchus is also known to have inhabited both continents.

[Smilodon P.]

In any case, it has been avoided that the oxalaia and sigilmassaurus are represented in figure form.

Too late. Say this to Guilherme Bilinski's Oxalaia model:

[Shonisaurus]

S @Smilodon P. Well in this case I close my mouth.  It is a pity that oaxalia did not exist. Anyway nice figure and thanks for the information provided. I did not know that such a collectible figure existed.

[stargatedalek]

And yet certain people here keep implying I'm loony for insisting it must have been marine...

[Nanuqsaurus]

So this would mean that Giganotosaurus and Spinosaurus both lived in South America around the same time, right? That's pretty crazy to think about. Would they have met?

[Smilodon P.]

S @Shonisaurus Don´t worry! If I remember correctly, there were few pieces made.

But, this changes some things, for example, the series of figures Dino Hazard intended to make an Oxalaia, because it appeared in the book.

But, given this paper, will they change the name? As the story takes place a little after the separation of South America from Africa and several animals from the fossiliferous record of these two continents (araripesuchus and Mawsonia, for example) or from the prehistoric African fauna appear, I always thought that they were open to possibility that Spinosaurus and Oxalaia were the same animal.

[suspsy]

And yet certain people here keep implying I'm loony for insisting it must have been marine...

I don't know about Spinosaurus being fully marine, but I definitely think the current evidence puts it roughly on par with crocodilians. And if saltwater crocodiles can colonize islands in the South Pacific that are thousands of kilometres from mainland Asia and Australia, then I reckon Spinosaurus could have swum from Africa to South America. Especially given that the Atlantic was much smaller back then.

[BlueKrono]

Looks like Ostafrikasaurus is on the outs too. Jurassic World made one for their Brawlasaurs line.

[Faelrin]

Not gonna lie, when I read that I immediately thought of "there is no Dana, only Zuul".

While I did like those names, it's really great to have some closure on this (well for the time being I suppose, unless further evidence was found contradicting it), that those remains did in fact belong to Spinosaurus after all, and just like Sarcosuchus being found in both continents at the same time (which S. imperator, was found in both the Elrhaz Formation, in Niger, Africa, and S. hartti was found in the Ilhas Formation in Brazil, South America).

A shame the article with all the data is paywalled (as typical I suppose), but at least there's the abstract. At first I was also wondering if this would keep the species names and only merging them under the genus Spinosaurus, but no it seems to be the species aegyptiacus as well.

A little thing interesting to note is that "Oxalaia" hails from the Alcântara Formation, which apparently also had remains attributed to both Spinosaurus and Sigilmassaurus as well at some point. What I didn't know was Carcharodontosaurus also has remains attributed to it from there as well. Mawsonia and Onchopristis, two of Spinosaurus' possible prey also have remains attributed to that formation (though possibly different species? I'd have to check). Seems like there was a lot that might have been getting around to both of those formations. Granted if this was during the span of several millions of years, that's like a large window of time for things like this to happen too.

I was also not aware until now that the Candeleros Formation (in Argentina) was contemporary with the Alcântara Formation (in Brazil), meaning that both Giganotosaurus and I guess now Spinosaurus, would have co-existed at the same time and continent, though it might be very unlikely the two ever met considering the distance between where they've been found. Also was contemporary with the Cerro Formation (in Argentina), which Dreadnoughtus hails from, and the Bajo Barreal Formation (in Argentina). Slight disclaimer is that my info is coming from the wikpedia pages, but so far the paleontology side of things there has been pretty reliable largely.

Here's a map from the wikipedia article on Oxalaia where spinosaurid remains have been found, for anyone as curious as I was about what the continental placement may have looked like back then:

[suspsy]

So this would mean that Giganotosaurus and Spinosaurus both lived in South America around the same time, right? That's pretty crazy to think about. Would they have met?

Impossible to say, since no one knows what the full ranges of Spinosaurus and Giganotosaurus were. Although Argentina is a long way from Brazil.

[Dinoxels]

Interesting. Maybe there was islands that Spinosaurus used to move from Africa to South America.

[Stegotyranno420]

Interesting indeed. I always knew oxalia and sigmilmassasaurus were just spinosauruses, but none believed me. Especially the part about SPinosaurus naturally fighting giganotosaurus is also interesting.

[Sim]

It's not as simple as one team of authors declaring a taxon is a junior synonym for the matter to be concluded.  It needs to be accepted by others in the scientific community too.  In the abstract of the paper, I noticed quadrates weren't examined and another paper has shown there are two morphotypes of spinosaurid quadrates from the Kem Kem beds, which don't differ because of ontogeny: https://www.researchgate.net/publication/289506620_Morphofunctional_Analysis_of_the_Quadrate_of_Spinosauridae_Dinosauria_Theropoda_and_the_Presence_of_Spinosaurus_and_a_Second_Spinosaurine_Taxon_in_the_Cenomanian_of_North_Africa

So, all the spinosaurid remains from the Kem Kem beds might not all belong to Spinosaurus, still.  I don't really like Sigilmassasaurus and Oxalaia, so I would prefer if they were junior synonyms of Spinosaurus, but the evidence suggests at least Sigilmassasaurus exists.  Although on that note I wonder if eventually Sigilmassasaururs will be considered a synonym of Spinosaurus maroccanus, the two are thought to be the same animal, and if the largest specimen of Spinosaurus ends up belonging to this species I could see people choosing to call it Spinosaurus maroccanus due to Spinosaurus's popularity and Sigilmassasaurus's lack of popularity.

On a final note I was pleased to see the paper consider spinosaurid tooth taxa nomina dubia, tooth taxa are so silly I would consider them all invalid.

[Gothmog the Baryonyx]

In light of Ceratosuchops and Riparovenator, the door has been opened for there being multiple Spinosaurids in one place and time.
Is that why you necromanced this thread @Sim ? It's still relevant today anyway I suppose.

[Sim]

I'd say the possibility of a number of spinosaurid species coexisting has been something real since the quadrate paper I linked to.  I posted in this thread because I was thinking of a question for the question game thread, was reminded of this thread, looked at it and saw the opinions didn't take into consideration the two quadrate morphotypes and so I decided to share my thoughts on it since it's still relevant today.

[Duck]

Slightly unrelated, wasn't Oxalia's holotype specimen destroyed in a fire?

[stargatedalek]

It's not as simple as one team of authors declaring a taxon is a junior synonym for the matter to be concluded.  It needs to be accepted by others in the scientific community too.  In the abstract of the paper, I noticed quadrates weren't examined and another paper has shown there are two morphotypes of spinosaurid quadrates from the Kem Kem beds, which don't differ because of ontogeny: https://www.researchgate.net/publication/289506620_Morphofunctional_Analysis_of_the_Quadrate_of_Spinosauridae_Dinosauria_Theropoda_and_the_Presence_of_Spinosaurus_and_a_Second_Spinosaurine_Taxon_in_the_Cenomanian_of_North_Africa

So, all the spinosaurid remains from the Kem Kem beds might not all belong to Spinosaurus, still.  I don't really like Sigilmassasaurus and Oxalaia, so I would prefer if they were junior synonyms of Spinosaurus, but the evidence suggests at least Sigilmassasaurus exists.  Although on that note I wonder if eventually Sigilmassasaururs will be considered a synonym of Spinosaurus maroccanus, the two are thought to be the same animal, and if the largest specimen of Spinosaurus ends up belonging to this species I could see people choosing to call it Spinosaurus maroccanus due to Spinosaurus's popularity and Sigilmassasaurus's lack of popularity.

On a final note I was pleased to see the paper consider spinosaurid tooth taxa nomina dubia, tooth taxa are so silly I would consider them all invalid.

Actually, there are three distinct giant Spinosaurs from the area! One seems very similar to Spinosaurus proper and is probably Sigilmassasaurus, if Sigilmassasaurus isn't just Spinosaurus, but has much bulkier neural spines. Probably a direct relative.

The other is this incredibly bizarre one with extremely thin neural spines that jolt sharply backwards, which means at least one convergently evolved giant theropod (I'm not 100% convinced it's a Spinosaur) was in the region. It's columns are even thinner than Baryonyx and Suchomimus, which is what makes me skeptical. It'd be neat if this was some kind of pathology but we'd definitely need a proper published study to gleam anything like that.

https://twitter.com/LordTrilobite/status/1433913756699009026



As for tooth taxa, I think there are situations where it's safe to name them, such as teeth that are very distinctly identifiable and don't match any contemporaries from nearby areas at the same time.