#sparassodonta

[extinctworld-ua]

Anachlysictis

Anachlysictis — рід вимерлих хижих ссавців з групи Sparassodonta, представник метатеріїв (група, що включає сумчастих та їхніх близьких родичів), котрі населяли Південну Америку протягом кайнозою. Типовий вид — Anachlysictis gracilis.

Повний текст на сайті "Вимерлий світ":

https://extinctworld.in.ua/anachlysictis/

[alphynix]

It's another PBS Eons commission roundup day!

The metatherian mammals Pucadelphys and Khasia, and lineart of the sparassodont Paraborhyaena, from "How South America Made the Marsupials"

https://www.youtube.com/watch?v=l5doyrUWFbE

  The dyrosaurid crocodyliform Acherontisuchus and the bothremydid turtle Puentemys, from "How a Hot Planet Created the World's Biggest Snake"

https://www.youtube.com/watch?v=T-hDNbM-WLk

  The early penguin Waimanu and the giant penguin Anthropornis, from "When Penguins Went From The Sky To The Sea"

https://www.youtube.com/watch?v=HMArjGQwLvY

———

Nix Illustration | Tumblr | Pillowfort | Twitter | Patreon

[synapsidgirl]

UK just went into a lockdown today, I have a lot of not very well defined thoughts about it, so naturally, I'm doing some Thylacosmilus studies. Here's the first one done. He's either just yawning, or maybe it's a threat display. Yes, his ears aren't flattened against his head, but I based this on thylacines, tasmanian devils, and american opossums who didn't/don't seem to be flattening their ears as a part of their threat displays either. At least that's what it looks like to me in pictures and videos. Of course, thylacines, devils, and opossums aren't related to Thylacosmilus, but since the jaws-agape-ears-not-folded threat display seems to be quite common among modern metatherians across different genera, I've decided to go with this, rather than ears-folded-lips-in-a-snarl placental thing. And yes, something bit his ear. I don't know what it was, but it doesn't seem to bother him much. I feel like I could have added more loose tissue around the lower jaw, since the lips would be so substantial, but I quite like how this turned out anyway. Also, I used yawning bloodhounds and basset hounds as reference for the lips situation, since they're very gifted in the jowls departament.

[thecoffeeisblack]

Final for Thylacosmilus atrox. In the 1920s Captain Marshall Field funded two expeditions to South America which were undertaken by the Field Museum of Natural History in Chicago, Illinois; these expeditions were launched under the hopes of finding fossils of mammals and other animals from the Cenozoic Era. In 1926, during the second expedition, a team was searching the Ituzaingo Formation in northern Argentina when they came across the remains of three animals thought to be never before discovered species of ancient marsupial. 

South America was prime real estate when it came to new discoveries due to it having been almost completely cut off from the rest of the world since the beginning of the Cenozoic and so expectations were high when it came to finding some uniquely adapted mammal specimens, it wasn't until 1933 when paleontologist Elmer S. Riggs named and described the specimens found on the Marshall Field Expeditions that science would realize just how right they were about the mammals of that time and place.

Thylacosmilus (meaning: "Pouched Knife"), was a member of member of a group called Sparassodonta, once thought to be true marsupials it is now considered to be a closely related group. Despite their resemblance to later placental predators like Smilodon fatalis, they were not closely related to them at all. Their saber teeth are an example of convergient evolution, where different, unrelated species develop similar traits to fill similar niches. Unlike felids, it's teeth grew backwards into their skull the older they got, they also did not possess retractable claws like most cats. Due to their short legs it's likely T. atrox were ambush hunters.

It was roughly 4.9 feet in length and weighed around 330 pounds and it lived during the Late Miocene to Pliocene, roughly 9 to 3 million years ago.

[majingojira]

A Prehistoric Writing Project

So, I’m working on a novella/story project which in essence is a sequel to Sir Arthur Conan Doyle’s The Lost World viewed as both an updating of the paleontology of the plateau, and a full alternate history project where a landmass as large as New Guinea is cut off from the rest of the world and maintains megafauna from various ancient eras (Cretaceous and Neogene, primarily). 

Now, paleofauna in South America is...weird. Far weirder than has been portrayed in any adaptation of followup to this story yet done.  While I do plan on some more familiar faces (albeit, done in ways that make them more accurate and thus new and exciting), I’d rather have fun with the weirdness.

But even with how fragmentary the fossil record is in South America, there’s a lot to choose from. 

So, I’m asking, what would you like to “See” in a “Realistic” version of such a Lost World?

[extinctworld-ua]

Proborhyaena

Proborhyaena — це вимерлий рід сумчастоподібних ссавців, який жив у олігоцені у Південній Америці. Вважається найбільшим із спарассодонтів.

Повний текст на сайті "Вимерлий світ":

https://extinctworld.in.ua/proborhyaena/

[synapsidgirl]

Bet you didn't see that one coming. I actually posted something! And this something is a lippy Thylacosmilus atrox, because why not? Plants are modern South American ones, because I couldn't really find anything useful about Pliocene S. American flora.

[thecoffeeisblack]

More work in progress on Thylacosmilus atrox.