The word “Mesozoic” makes most people think of dinosaurs, and that’s not a bad thought. But, the first chunk of the Mesozoic, the Triassic (252 to 201 million years ago), offered a whole bunch of other cool experiments in life. For most of the Triassic period, dinosaurs weren’t the largest, most common, or even the coolest vertebrates on land. Dinosaur cousins (along with dinosaurs, they’re all members of a group called archosauromorphs) take the prize.
Our latest entrant in the category of “Weird Triassic Archosauromorphs,” and tied for sixth/seventh place for the Top 10 Open Access Fossil Taxa of 2017, is Shringasaurus. This Triassic critter was announced in August, by Saradee Sangupta and colleagues.
When I was a kid, I loved drawing prehistoric animals. Of course, I penciled out the standard tyrannosaurs and pterosaurs and such. When I got bored, I would do fanciful hybrids, putting a T. rex head with a sauropod body and ankylosaur tail club, with some stegosaur plates for good measure (not all that different from the approach used in the latest Jurassic World movies). Shringasaurus is basically a real-life implementation of my childhood daydreams!
Imagine, if you will, a squat and scaly animal measuring around 3 to 4 meters long; it’s about the bulk and build of a small cow (at least in the torso). The critter has a slightly humped back, which would be about waist-high to a human. It’s probably a bit too small for a typical adult to saddle up and ride around, although my five year old probably could if the animal didn’t object. There’s a longish neck, and the head (about the length of a dinner plate) roughly resembles that of an iguana. I say “roughly,” because even if the overall shape is somewhat similar, this comparison is jolted by two spikes protruding from above its eyes! These horns are about as long as your hand, and each is shaped like a fat carrot.
Shringasaurus lived around 245 million years ago in what is now central India, the state of Madhya Pradesh. Back during this part of the Triassic, the sub-continent of India was far south of its present-day connection to Asia. India was nestled up against what is now Madagascar and Antarctica, all as part of the supercontinent of Pangaea. In fact, you could walk from Mumbai to Buenos Aires without having to cross any oceans. These geographical connections meant that Shringasaurus has a whole bunch of close relatives in what are today well-separated localities, virtually worldwide. Azhendosaurus, its smaller hornless “sibling”, has a very similar body shape and occurs in both Morocco and Madagascar.
The research team that studied Shringasaurus suggests that it used its horns for combat with other members of its species. Interestingly, not all Shringasaurus have horns; this is suggested to be evidence of sexual dimorphism (e.g., horned males and hornless females), although I also wonder if it could just be evidence of different growth stages (although some horned and hornless individuals are roughly the same size).
Shringasaurus is important not just for its cool headgear, but also for the abundance of material. A single locality yielded parts of at least seven individuals, with nearly all bones of the skeleton represented. This is a great resource to better understand the anatomy and individual variation within an early archosauromorph. Shringasaurus definitely earned its spot in our Top 10 list!
Image credits: All images modified from Sengupta et al. 2017. CC-BY.