Placerias: Chonky Herbivore that Roamed the Late Triassic Period
Chonky!
Placerias is a large, herbivorous #dicynodont that roamed the Late #Triassic period, approximately 221 to 210 million years ago. This cast is on display at the Petrified Forest National Park in my beloved state of Arizona, where numerous elements have been found. It lived primarily in the southwestern United States.
A #therapsid, often referred to as “mammal-like reptiles,” a term no longer used as it doesn’t properly convey their evolutionary origins. As I have evolved so has scientific knowledge. I feel this most keenly in animals I learned about in the 80s and 90s, only to discover progress in other groups can render even some baseline knowledge out of date. It also means I learn new facts about every critter I see. :-)
Placerias was my kind of herbivore, stocky and barrel-chested, measuring up to 12’ in length and weighing over a ton. It needed every bit of that size as it lived in dangerous times.
The skull has a distinctive beak-like structure, which it used to shear through tough vegetation. And likely to remove a few inches of skin from marauding predators and conspecifics squabbling over a prime patch of feed.
It had two elongate, protruding canines possibly used for digging up roots and tubers, as well as for defense and intraspecific competition.
Those tusks, especially when combined with that “beak,” made it a formidable forager in the diverse Late Triassic ecosystems. #Phytosaurs and #rauisuchians would think twice before taking on a full-sized adult, no different than predator-prey interactions today.
Placerias lived in semi-arid environments with seasonal climates, where it likely congregated near water sources such as rivers and lakes. Its lifestyle was similar to that of modern large herbivores, possibly living in herds for protection against predators. I wonder how hippo-like it was.
Speaking of #hippo, I wonder if being so chonky and round makes it more difficult for predators to take down. Stout and low to the ground, it wouldn’t knock over easy. Being round means it’d be hard to get a fatal bite, slicing into fat, while injurious, isn’t as debilitating as muscle severance.
#FossilCrates