Thursday, October 16, 2014

Species that don't get enough publicity #9: Rajasaurus narmadensis and the Lameta Formation

With the passing of the one-year anniversary, I’m going to return to my peak output.  I’ve been distracted, but now I’m back.  So today, we’re going to feature another dinosaur.  This one’s a fairly recent one, but part of an interesting story in both its history as an animal and its history in paleontology. 

Everyone loves the big scary dinosaurs. When William Buckland was given a big jaw with a serrated, curved tooth from Stonesfield quarry in  1815, he was fascinated by it, and thanks to the ferocious reconstruction by Benjamin Hawkins it became an icon of antiquity. Cope’s Dryptosaurus in 1866 and Marsh’s Allosaurus 1877 brought dragons back to life. The apex came with the legendary Tyrannosaurus of 1905.  People like their animals big, scary, and extinct, and Tyrannosaurus is the epitome of all this.

So I’m not going to talk about Tyrannosaurus, but a contemporary. This one’s been only described fairly recently, but its story is intertwined with mysterious bones found in 1932. This is the story of Rajasaurus, but it’s also a story of the Lameta Formation near the Narmada River next to Jabalpur in Madya Pradesh.

Our story begins in 1877 in the British Raj.  Social reforms are on the rise. The middle class of educated Indians is finally making strides. India has come a long way since the oppression and exploitation of the EAC’s rule. British scientists scour the now-stable area, studying the people, the animals, and the land itself. England is still in the middle of its Indophilia, just not at the point of granting them independence. The Russians and Germans, as well as the bloodbath of 1857, have scared off that idea, but the few nationalists still cry out.

Natural Richard Lydekker begins the saga with his natural history of India. He finds sauropod bones. A world away, Othniel Charles Marsh discovers Brontosaurus and Edward Drinker Cope discovers Camarosaurus, so Lydekker has no idea what they are. There’s been giant bones like this before, but these seem even bigger. Lydekker dubs this assortment of vertebra and limbs Titanosaurus. He doesn’t know what kind of animal they are, only that they are of a giant reptile that came much later than the dinosaurs he was familiar with.  He finally classifies it as a sauropod dinosaur in 1895, now that the giant American dinosaurs have been found.

1917. The rest of the empire shudders under the carnage of the Great War, but India remains safe. Geologist Charles Matley collects more bones near Jabbalpur. They are a jumbled mess of various animals, but he recognizes carnivore teeth. He calls it the Carnosaur Bed (Carnosauria is Frederick Von Huene’s invention, containing all giant meat-eating dinosaurs).  In 1923 he names one of the animals Lametosaurus after the locale, and changes his mind that it’s a Carnosaur to that opinion that this animal is a Stegosaur. It’s a jumbled mess of armored scutes, a fractured pelvis, and carnivore teeth, all from different animals.  The material’s all disappeared since then, leaving an enigma that may never be solved.

A one inch theropod tooth is found by an  H. C. Dasgupta in 1931, called Orthogoniosaurus and mistakenly placed in the Triassic as a Massopondylid. Suffice to say, it doesn’t count for much.

1933, however, was the field year. Mately returned, joined forces with Von Huene, and they described no less than 8 new dinosaurs from Lameta. Indosaurus, the skull roof of an allosaur (later discovered to an abeliosaur), Composuchus,  the neck of a theropod, Coeluroides, the tail of a small theropod, Dryptosauroides another small theropod tail,  Indosuchus, the skull fragments of a medium-sized theropod, Antarctosaurus, the torso and limb of a big sauropod (later given its own species Jainosaurus, as the original Antarctosaurus was a distant relative from Argentia), Jubbulpuria  yet another small theropod tail, Laevisuchus, the back and tail bones of a small theropod, and Ornithomimoides another small theropod  

With the exception of Jainosaurus and Indosuchus (which may be the same animal as Indosaurus), most of the material is now either lost or nondiagnostic. Suffice to say, there were many small theropods at Lameta.

One thing clarified the theropod situation, however- in 1985, Jose Bonaparte and Fernando Novas discovered two new theropod dinosaurs: Abeliosaurus and Carnotaurus. These were contemporaries of the Lameta dinosaurs, but from very complete specimens. Big predators, they were determined to be neither related to Megalosaurus, Allosaurus, or Tyrannosaurus, but descendants of the American horned carnivore Ceratosaurus. Abeliosauridae was born.

In 1934 a new mystery specimen was found-Indian geologist Dhirendra Kishore Chakravarti thought it resembled a stegosaur, naming it Brachypodosaurus!  Currently, the last of the Stegosaurs seemed to be the Chinese Wuerhosaurus and the British Regnosaurus. It’s just a humerus, but it hasn’t been given a good study, and it may not show any distinguishing stegosaur features. Another late Cretaceous stegosaur, Dravidosaurus from Ariyalur, has been discovered to be badly-preserved plesiosaur material. Hopefully someday this mystery will be solved.

In 1984, the definitive Indian titanosaur was finally found at Dongargaon Hill near Manjar Sumba in Maharashtra. Sohan Jain and Saswati  Bandyopadhyay of the Indian Statistical Institute named it Titanosaurus colberti after the great paleontologist Edwin Colbert in 1997, but Jeffery Wilson and Paul Upchurch found it distinctive enough to be it’s own species. Isisaurus is named neither after the Egyptian goddess or the Muslim fundamentalist polity, but for the Indian Statistical Institute to which it belongs. Only the skull, hindlimbs, and feet are missing, giving a picture of a 60-foot animal with a very thick neck and long legs; a strange animal indeed. 

The star of today’s article was found far away from the Lameta site, although it is part of the same fossil formation as it stretches across the north of the subcontinent.  The Narmada river travels west from Madya Pradesh into Gujarat where it empties into the Gulf of Khambhat, and it is at a small town called Raholi that this animal was found.

In 1981, geologists G.N. Dwivedi and D.M. Mohabey found Cretaceous fossils at a ACC Cement quarry near Raholi, including large, round, dinosaur eggs. In 1982, Suresh Srivastava of the Geological Survey of India  retrieved a large, half-complete skeleton and with the aid of his supervisors D.K. Bhatt, S. C. Pant and U.B. Mathur managed to extract the bones. After a pause for input from Prof.Ashok Sahni and Ashu Khosla of Puynjab University, Srivastava invited Gondawanan (the Southern continents of the Mesozoic, Africa, India, Australia and South America) paleontology experts Jeffery Wilson and Paul Sereno to help describe the animal. In the meantime, more material was found from the Lameta site. In 2003, they finally released the paper, naming this new predator Rajasaurus, king lizard.

The GSI has since made the Rajasaurus a mascot-an Indian equivalent of Tyrannosaurus rex. A cast of the skull was sent to Kalkota’s Indian Museum. Princess Aliya Babi (daughter of Nawab Muhammed Salabat Khanji II) of Balasinore promotes the site and uses her interest in paleontology to promote tourism and attention in Gujarat. 

Two other predators have been found since then, both also from Kheda District: the gracile sister taxon Rahiolisaurus  and the large snake Sanajeh. Sanajeh, the size of a large boa constrictor but more closely related to South American Najash , was found in a sauropod’s next among its eggs and hatchlings. This raises the possibility that it fed on baby sauropods (the jaw is not detachable as in many modern snakes, forcing the animal to eat smaller prey).  The giant (fragments suggest more than 20 feet) snake Madstoia, its closest relative, was also found near titanosaurs, and may have eaten larger individuals than Sanajeh.

Neither of them, however, were as massive as Rajasaurus. 30 feet long, 4 tons in weight, it was the apex predator of the ecosystem. The 2-foot skull, armed with serrated two-inch teeth, was built to hack into sauropods and inflict bloody wounds. It was heavily built for an abeliosaur, meaning it specialized in large prey.  Like its contemporaries Carnotaurus from South America and Majungasaurus from Madagascar, the skull was short and deep. This meant it was sturdier, and in all three genera was thickened on top, possibly to head-butt rivals during competition. They all were about the same size, lived in similar habitats, and ate the same kind of prey. A smaller European relative, Arcovenator, was also a contemporary, while Tyrannosaurus and its sister genus Tarbosaurus ruled North America and Asia.

Rajasaurus, unless we find an even bigger specimen, was not the largest abeliosaur, however. That prize goes to both the middle Cretaceous Argentinian Ekrixinatosaurus unnamed species from the Turkana Grits in Kenya, both more than 35 feet long. However, their specimens are not nearly as complete, or in the case of the Kenyan monster, even published yet.  In the meantime we have our southern triumvirate.

Carnotaurus is quite popular, with many toys, many artistic depictions, a full-scale model with realistic skin, and even played the villain in Dinosaur.  Majungasaurus has been featured in the TV documentaries Jurassic Fight Club, Planet Dinosaur, and Dinosaur Revolution, with emphasis on its aggression and evidence of cannibalism.

Alas, among Gondawanan animals, the Indians get the least attention. Rajasaurus is still popular in India, and the toy company CollectA has made a toy of it (like most of their figures, sadly, the sculpting is atrocious), but it’s still very obscure. Every nation wants their own dinosaur at the top, and like most nationalism, it gets very old very quickly.  Perhaps as India grows in power and Indians become more educated and global, Rajasaurus will be the new king.

So anyway, Hollywood, give this guy a break. Museums, put him on display. Toy companies, here’s a new fresh face. Authors, think about the crap you’re writing and how this genus could perk up the place. And remember, shop Rajasaurus where you work or play.

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