Megapterygius, new genus of mosasaur from Japan with skeletal features suggesting a dorsal fin

[Faelrin]

Here's the paper (paywalled unfortunately):

https://www.tandfonline.com/doi/full/10.1080/14772019.2023.2277921

[SidB]

Here's the paper (paywalled unfortunately):

https://www.tandfonline.com/doi/full/10.1080/14772019.2023.2277921

If this truly were to possess a dorsal fin, it would be a most remarkable thing for a member of this clad to have gone from no suggestion of one to the distinct possibility.

[Halichoeres]

My first thought when I saw the genus name was, that's awfully close to the humpback whale (Megaptera), which is also famously long-finned among whales. Sure enough, there are lots of allusions to the humpback whale throughout the text, although they don't specifically cite it in the official etymology.

Anyway, here's the skeleton:

Pretty decent fraction of the animal! The forward-swept neural spines at the back of the rib cage, reminiscent of those in whales, are the trait they're using to infer a dorsal fin. It's circumstantial, but intriguing.

If anyone wants a pdf, pm me your email address.

[Prehistory Resurrection]

Found an article; https://www.earth.com/news/blue-dragon-terrorized-the-pacific-seas-72-million-years-ago/
Very amazing, unbelievable find. That's almost the complete skeleton that's been found.

Very curious about the dorsal fin.  So, that makes the Papo Mosasaurus accurate?

 What an irony! This was the same case with their Limited Edition 2019 Spinosaurus when they gave it the paddle-like tail which was speculative, but it turned out afterwards that it indeed had such a tail.
This reconstruction of an also recently discovered plioplatecarpine mosasaur discovered in Mexico; Yaguarasaurus, also shows it with a dorsal fin:

[Faelrin]

@Prehistory Resurrection I would say it is too early to say (regarding the Papo Mosasaurus, and other mosasaurs having this feature). It could be something specific to this genus, or it could be more widespread.

Turns out that other mosasaur is actually a second species of an existing genus. I think that artwork falls into the same scenario. Speculative, and too early to say.

The Papo Spinosaurus is interesting in that regard, but the morpology of the real specimen did have a much different structure to its skeleton compared to the Papo one. Only the overall shape and perhaps idea is somewhat similar, but it is not accurate to what was eventually found (granted that is no fault of their own, it wasn't yet known then).

That said yeah this Papo Mosaurus does have a similar situation to the Papo Spinosaurus, as you said. They did something speculative and there's something similar found shortly after the figure released (in the same year). I suppose some folks might want to pick this figure up to stand in as this genus, although porportions are different.

[Reuben03]

My first thought when I saw the genus name was, that's awfully close to the humpback whale (Megaptera), which is also famously long-finned among whales. Sure enough, there are lots of allusions to the humpback whale throughout the text, although they don't specifically cite it in the official etymology.

Anyway, here's the skeleton:

Pretty decent fraction of the animal! The forward-swept neural spines at the back of the rib cage, reminiscent of those in whales, are the trait they're using to infer a dorsal fin. It's circumstantial, but intriguing.

If anyone wants a pdf, pm me your email address.

i would quite like that! I have lost my pdf copy i'll have to pm you