Name: Aerosteon riocoloradense
Name Meaning:Río Colorado Air Bone
First Described: 2009
Described By: Sereno et al.
Classification: Dinosauria, Saurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Allosauroidea, Allosauria, Carcharodontosauria, Neovenatoridae, Megaraptora
Aerosteon was another megaraptorid that was about 9 meters long and a little over 3 meters high. It was found in the Anacleto Formation in Argentina, and it lived in the Santonian stage of the Late Cretaceous, about 84 million years ago. Its classification is under some debate and it has been considered a tyrannosauroid. As it is only known from scattered remains, more specimens should be found before any real conclusions can be made about its classification. It had air filled spaces in its bones, giving it very lightweight bones and its possible that it had an avian like respiratory system, making me fairly convinced it should be rendered with feathers. This would have allowed for greater airflow to and from Aerosteon’s lung, allowing it to regulate its temperature and breathe faster, making it a very active predator.
Shout out goes to xtori34!
Name: Mapusaurus roseae
Name Meaning: Rose Earth Lizard
First Described: 2006
Described By: Coria & Currie
Classification: Dinosauria, Saurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Carnosauria, Allosauroidea, Allosauria, Carcharodontosauria, Carcharodontosauridae, Giganotosaurini
Mapusaurus was yet another huge carnosaur from the Cenomanian stage of the Late Cretaceous, about 95 million years ago. It was found in the Huincul Formation in Argentina and was a contemporary of its close cousin Giganotosaurus. Its original discovery was amongst seven other individuals, making it probable that it hunted in packs. This completely challenged the notion that predatory dinosaurs were solitary animals. The individuals in the bone bed were all different ages and no other species were present, supporting the pack hunting hypothesis. Since it lived alongside Argentinosaurus, it probably used pack hunting to bring down the huge prey animals available to it, targeting weaker members of the herd and waging a war of attrition on them. It is possible that this was just a depositional area from a stream or a river, but given the lack of other specimens, I doubt it.
Mapusaurus, like Giganotosaurus, had flat and curved teeth with a serrated edge, built for slicing through flesh. The packs of Mapusaurus would probably slice through the Argentinosaurus and wear down the animal with shock, blood loss and infection. It differs from Giganotosaurus in a few ways, mainly in the shape of its skull, arms, pelvis, and legs. However the two are very similar. It was at least 10 meters long but probably longer, and three meters high. Mapusaurus also lived with Cathartesaura and the abelisauroids Skorpiovenator and Ilokelesia, which would likely have competed with it for food.
Shout out goes to my friend sylph0fl1ght!