Eotyrannus lengi

Eotyrannus lengi (pronounced 'Ee-oh-tie-ran-us') is one of the most recent Isle of Wight dinosaur discoveries.  It is believed to be from a group of dinosaurs called tyrannosauroids, that later included Tyrannosaurus rex which first appeared over 50 million years later. There is only one incomplete skeleton, the holotype, IWCMS 1997.550. The bones from this fossilised creature are quite fragile, and they are entombed in a very hard matrix of grey and brown iron-rich rock. What marks Eotyrannus out as unusual are its long hind legs and hands. Eotyrannus is still being studied, but Dinosaur Isle currently displays parts of the skull and various hand elements, along with a superb life-sized restoration.

During 1995 local collector Gavin Leng brought a claw he had found on the beach to Steve Hutt at the old Museum of Isle of Wight Geology at Sandown.  Over the next few weeks the site was carefully excavated, and the fossils removed.  Due to the nature of the find the site was kept secret. Over the next few years the fossils were carefully researched in conjunction with scientists from the University of Portsmouth, and with help from the Natural History Museum. Finally in 2000 the dinosaur was named as a new genus and species, with the species name taken from Gavin Leng's surname in honour of his being the first to find it. The research announcing the new name was published internationally in January 2001.

Like many other dinosaur remains we have only found the preserved bones and teeth. What makes the discovery of Eotyrannus remarkable is that we have so much of the skeleton preserved, and enough parts to attempt a reconstruction of what the dinosaur might have looked like.

The fossils are now contained in a hard grey rock which make them very difficult to extract. They have been blackened through soaking up minerals in the ground over many thousands of years before finally being changed to rock. The photograph above shows a number of the jumbled-up bones (taken in 2011) including some from the shoulders, arms and feet encased in one block of rock.

The fossil remains discovered so far are from one individual, and are the only known material from this dinosaur.  The initial research paper produced by Steve Hutt (from the Museum of Isle of Wight Geology) and scientists from the University of Portsmouth in 2001 reported the following list of bones;-

parts of the skull, including the dentary and some teeth; various vertebrae from the neck and back, and possibly tail; shoulder girdle, radius and ulna, carpal, metacarpals and some phalanges including the distal phalanges; parts of the pelvis; and from the legs, most of a tibia, a fibula, metatarsals and phalanges, including one pedal distal phalange.


Photograph of one of the fingers of Eotyrannus.


Photograph of two more fingers from Eotyrannus.


The mdf model of the skull in the image indicates parts of the skull that we have identified in the rock matrix so far (painted in black).

Because it was described formally this makes the Eotyrannus at Dinosaur Isle the 'holotype', or type specimen.  All of the fossil remains from this one animal have been catalogued under the reference: IWCMS 1997.550. 

What makes this creature even more intriguing is that some of the bones are articulated, whilst others have been moved to entirely new positions (was this animal partially scavenged after it died?). The blocks of rock also include bones from two other dinosaurs of different types, so the mystery continues as to how it died; we may never know.

Systematic palaeontology
Dinosauria  Owen, 1842
Saurischia  Seeley, 1887
Theropoda  Marsh, 1881
Tetanurae  Gauthier, 1986
Avetheropoda  Paul, 1988
Coelurosauria  Huene, 1914
Maniraptorformes  Holtz, 1996
Tyrannosauroidea  Osborn, 1905
Genus Eotyrannus gen. nov. 
Eotyrannus lengi Hutt et al, 2001

Research
Comparatively little research has been carried out on Eotyrannus compared to some other Isle of Wight dinosaurs.  After the initial research published in 2001 by Hutt et al, there was little further work published. However that situation is now changing amidst a renewed global interest in small carnivorous dinosaurs.

Parts of the Isle of Wight Eotyrannus featured in comparative research into early (basal) tyrannosauroids carried out by Stephen L. Brusatte and Roger B.J. Benson of the American Museum of Natural History and the University of Cambridge, England respectively, published in Acta Palaeontologica Polonica in 2013.  We await the publication of further research currently being undertaken by Darren Naish of the University of Southampton, England.


References
Brusatte, S. & Benson, R. 2013. The systematics of Late Jurassic tyrannosauroid theropods from Europe and North America. Acta Palaeontologica Polonica. Vol .58, No.1. p47-54.

Hutt, S., Naish, D., Martill, D.M., Barker, M.J. & Newbury, P. 2001. A preliminary account of a new tyrannosauroid theropod from the Wessex Formation (Early Cretaceous) of southern England. Cretaceous Research. 22, 227-242.

Martill, D.M. & Naish, D. 2001. Dinosaurs of the Isle of Wight. Field Guides to Fossils: Number 10. Palaeontological Association. p290-295.

Naish, D. 2011. Theropod dinosaurs. In Batten (ed.). English Wealden fossils. Field Guides to Fossils: Number 14. Palaeontological Association. p548-551.

Size
Measurements of some of the limbs suggest the animal would have been about 4 to 5 metres long; however some of the bone sutures are not fully fused suggesting that the specimen was not an adult. For a length of 4 to 5 metres the height is estimated to be from 1.5 to 1.8 metres.

Weight
to be announced.

Eats
Meat, possibly other small dinosaurs like Hypsilophodon and young Iguanodon.

How fast could it run?
We don't yet have a figure to announce, but this dinosaur had very long hind legs and, for its size, may have been the fastest running predatory dinosaur on the Island.

The geology and age
Lower Cretaceous
Wealden Group
Wessex Formation

Due to the secure location of the site we can only say that Eotyrannus was living on the Island somewhen between about 123 to125 million years ago.

Where was it found?
In Brighstone Bay on the south-west coast of the Island.  The exact location is being kept secret to protect any further remains that might become exposed.

When was it first found?
In 1995 by Gavin Leng.

Something different or unusual?
Eotyrannus has very long fingers.

Only one of these creatures has been found so far, making it a rare find.  David Martill and Darren Naish (2001) speculated that this may have been a solitary creature that roamed into the area from the higher, and perhaps wooded, land to the north.  But of course carnivorous hunters are at the top of the food-chain today and there are always far fewer than their prey so perhaps there just weren't as many to start with. Its long legs suggest that it was a fast runner, and may have chased down prey rather than scavenging for food.

The one specimen of Eotyrannus was found by Mr Gavin Leng, after whom this new dinosaur is named (Eotyrannus lengi means 'Leng's early tyrant').  The origins of dinosaur discovery probably go back hundreds of years or more with bones and teeth found by Chinese farmers, and elsewhere in the world where agriculture or landslides disturbed the soil.  However it wasn't until the Victorian era that the first real attempts to discover and classify dinosaurs began.  Speculation on what dinosaurs looked like created the strange blocky animals we sometimes still see in old books. After a long period of time during the first half of the 20th Century when exploration and research declined due to a series of global wars the last few decades have seen a new explosion in the identification of new dinosaurs.  Eotyrannus is one of the latest exciting creatures to be found during the current golden age of dinosaur discovery. Recent similar finds in China make our local dinosaur even more important, and link the current research with those Chinese farmers who first found dinosaur bones centuries ago. Perhaps these ancient finds of large skeletons, and skulls filled with sharp teeth, contributed to the origins of the story of dragons?

Research has been taking place into the holotype, and its relationship to other meat-eating dinosaurs. of similar type.  Because some of the fossils are still entombed in rock matrix this presents an opportunity for some additional research into the micro-fabric of the rock to investigate aspects of the palaeo-environment and burial history.  At present only part of the fossilised remains are on display; we aim to have all of Eotyrannus on view in the future, and then to be able to present a summary of new research conclusions.

Trevor Price, Dinosaur Isle. From articles quoted, research papers and images from the collection at Dinosaur Isle Museum, Culver Parade, Sandown, Isle of Wight, England PO36 8QA