Still catching up with posts I need to write given that the past two weeks were just major paper after major paper. Given that the last two I did were on the recently named sebecoid Tewkensuchus (more here) and on the unrecognized diversity that slumbers among modern American crocodiles (see here), it sure would be convenient if there was one that sorta ties into both of those....
Oh yeah, what convenient timing for "A South American sebecid from the Miocene of Hispaniola documents the presence of apex predators in early West Indies ecosystems", written by Lázaro W. Viñola López and colleagues and published literally just last night as of the time I'm writing this.
What's this paper about? Simple, the description of sebecid fossil remains from the island of Hispaniola. Sebecids of course being terrestrial crocodile relatives that lived throughout much of the early Cenozoic in South America. The remains admittedly aren't anything to write home about, consisting of two vertebrae and a tooth with the group's iconic blade-like serrated morphology (aka ziphodonty), but the implications are nonetheless quite interesting. Not only is it the best evidence we have for insular sebecids and would have been the islands apex predator, but it also extends the survival of Sebecidae by perhaps up to 5 million years. This means the group might have survived until the Early Pliocene.
The Hispaniola sebecid, tentatively assigned to Sebecus sp., as illustrated by Machuky Paleoart
Now full disclosure, these remains are NOT the first evidence of what could be sebecids from the Caribbean. Previous discoveries include teeth from the early Miocene of Cuba as well as the early Oligocene of Puerto Rico. However, what makes the Hispaniola remains so much more important is surprisingly the presence of vertebrae. Hear me out. Sure, the teeth are iconic and easily identifyable, however, ziphodont teeth are not unique to sebecids and have also evolved independently in more "modern" crocodiles such as planocraniids and mekosuchines. Sure, mekosuchines were definitely not hanging out on Hispaniola and planocraniids are accepted to have died out during the Eocene, but nonetheless this means that ziphodont teeth could also belong to another type of croc. HOWEVER, the vertebrae from Hispaniola are described as amphicoelous, while animals closer to todays crocs would have procoelous vertebrae. Ergo, ziphodont teeth + amphicoelous vertebrae = sebecid, making these remains the first unambiguous evidence for Caribbean sebecids.
A simplified phylogeny showing the repeated evolution of ziphodont teeth in crocodyliforms while also highlighting the diferences in notosuchian and eusuchian vertebrae.
Case and point for why thats important? Well while the remains from Cuba and Puerto Rico are most likely also sebecids based on their age and geography, there are even older fossil remains of a ziphodont croc from the Middle Eocene of Jamaica. While sebecids were already around back then, so were the planocraniids, hooved crocodile-relatives found across North America and Eurasia. And since Eocene Jamaica has faunal similarities with North America, this particular ziphodont is more likely to be a planocraniid than a sebecid.
While the Cuban and Puerto Rican teeth are likely those of sebecids, the Eocene Jaimacan ziphodont croc could have easily been a planocraniid similar to the widespread genus Boverisuchus, illustrated here by Corbin Rainbolt.
Those that read my post on Tewkensuchus might remember my barely coherent ramblings about how confusing and poorly understood the paleogeography of sebecids is. Well for what its worth, if we ignore all the chaos caused by Europe's part in the equation, the South American history is relatively straight forward. The Paleogene record spans both remains found in the far South as well as Eocene records further north at lower latitudes. It's not entirely clear how sebecids got to the islands, but it is speculated that they could have rafted or even traveled across temporary land bridges that formed at times of lower sea levels. Whatever the case, by the early Oligocene sebecids seem to have made it to Puerto Rico and would have likely been isolated from the mainland and from other island populations when various marine passages opened, splitting the island chains. This may have been a blessing in disguise, as by the Miocene sebecids were restricted to tropical environments at low and mid latitudes and further habitat collapse, tied in part to the disappearance of the Pebas Mega Wetlands, eventually lead to their extinction on the mainland by the early Late Miocene.
But if the fossils from Hispaniola are anything to go by, then they clung onto life for another 5 million years in the Caribbean, retaining their spot as the islands apex predators until possibly as late as the Early Pliocene. Alas, they couldn't evoid extinction forever and unless we find even younger remains the Hispaniola sebecid represents the last hold out of the once diverse group Notosuchia.
Predator guilds and their distribution in South America throughout the Paleogene (a), Neogene (b) and late Quaternary (c).
But in a way, they didn't go without leaving their mark on the island. After sebecids went extinct, there seems to have been a push by native birds towards more terrestrial life, with some species losing the ability to fly alltogether. Some birds of prey seem to have taken up the mantle of terrestrial predator, leading to owls like Ornimegalonyx on Cuba and even the only distantly related Cuban crocodile threw its hat into the ring when it came for the spot of apex predator.
Top: A cuban crocodile hunting a small species of ground sloth, illustrated by Manusuchus
Bottom: A general overview of the fauna found on Cuba during the Pleistocene, including flightless birds, cuban crocodiles and terrestrial owls, illustrated by Joschua Knüppe
Literally my first time ever drawing Engineer, and second anything Team Fortress related. I've been thinking about tf2 a lot recently, and thought of him at the same time as Sebecus, so I drew both. Dogodile
The wolf-like Sebecus icaeorhinus was a crocodylomorph from the Eocene of South America. It is the type species of the carnivorous, terrestrial Sebecosuchians, and named after the ancient Egyptian crocodile god Sobek.
Sebecus lived in a diverse South American ecosystem. It would have lived alongside Phorusrhacids (“terror birds”) and other birds, caimans, Astrapotheres, notoungulates such as Cochilius, notohippids such as Eomorphippus, litopterns like Theosodon, armadillos like Peltephilus and glyptodonts like Propalaehoplophorus, metatherians like Borhyaena and Cladosictis, monkeys, bats, snakes, frogs, turtles, and much more.
While not quite large enough to take on the giant tapir-like Astrapotheres, Sebecus was probably quite capable of preying on animals similar to its own size. With its extra strong jaw closing muscles and serrated teeth, it was likely adept at crunching through the hides and even bones of more armoured animals.
hey do you guys have any sort of rough idea of when yagami's route will be finished? o: like no rush or anything i totally dont mind waiting im just lookin forward to it!!
Hey there! I’ll be honest, my wife hasn’t been able to work on translation in a while because of work projects and personal stuff, but she’s getting back into it now. :3
We actually have a bunch of text that’s done, but just needs final checks and formatting before it can be posted. It’s about 13 pages out of 80 total done so far, so it’s a pretty big chunk! We’ll probably have that finished and posted by the end of the weekend if Persona 5 doesn’t eat my soul.
After that, there’s still a bunch more to be translated before the end of the route - there’s about a third of the original Japanese text left even after you include the parts that are translated and not posted yet.
Yagami’s route is looooooooooooong. _o_
I’m not sure how much longer the rest of his route will take cuz my wife’s work is always pretty insane and she’s toast in the evenings (it’s almost 2 hours past her time to leave but she’s still working right now grrrrrr!) buuuuut I’ll ask her and post a legit reply later instead of just rambling on like a doofus 8D
wait too late I already rambled on like a doofus
(other stuff to look forward to soon: Arata’s “my feelings that time” subbed video and Takato’s long-ass Cool-B story! :Db)
