Baryonyx walkeri

            Here is the most complete theropod dinosaur known in Europe at the time of its discovery.

Discovery

It was 1983 that the amateur fossil hunter William (or Bill) Walker stumbled upon a huge curved claw sticking up out of the side of a clay pit in the Smokejacks Pit at Wallis Wood, Ockley near Dorking in Surrey, England. He had tried to dig out the claw but it crumbled between his fingers. Luckily he was able to reassemble the claw and he began to search for what it might be in various fossil identification books. He just couldn’t seem to figure it out. What was it or what did it belong to? Finally, he decided to contact the Natural History Museum in London. They to could not give him a definite answer but decided to come and investigate for themselves.

After being directed to the discovery site of the claw, dig team leaders Alan J. Charig and Angela C. Milner began to dig up an entirely new species of dinosaur! After three years of digging in the hopes of finding more. Having about 70 percent complete, it was the most complete theropod dinosaur skeleton discovered anywhere in the world and it was also the only large theropod discovered in England at that time. The description was published by Charig and Milner in 1986 and was named after Walker at about the same time.

The BMNH R9951 (HoloType) is now mounted and being display at the Natural History Museum for guests to view. This specimen was probably a juvenile (at about 9 meters long) because of infused bones in the skull.

Since then more fragmentary specimens have been discovered but none in nearly as good a condition as the BMNH R9951 specimen. Some are worth mentioning, though. For instance a partial skull was found in the Sala de los Infantes deposit of Burgos Province, Spain. Also some of the famous and plentiful dinosaur tracks of La Rioja, near Burgos, may have been Baryonyx or at least a theropod similar to Baryonyx.

Two more claws were discovered in the Niger Republic in West Africa as well as a third on the Isle of Wight in 1996. A more recent Baryonyx find is a vertebrae found near Barnes High. It had a fairly long spine on its back and is supposed to be shown at the Dinosaur Farm Museum. A cast of this specimen was on display at the SVPCA in 2004 in an attempt to prove the synonymy of Baryonyx and Suchomimus (which is very likely, in my opinion). Also, a small claw was found by Martin Simpson and identified as part of a manual ungual of Baryonyx.

In 1998 a manual phalange (supposed to be the very one that supported Baryonyx’ large claw) was taken by the Isle of Wight Geology (now Dinosaur Isle) from the Carisbrooke Castle Museum. Often times, when scientists discover a fossil that seems unimportant, they will place it in museum storage or a basement. Such was the case with this forearm found on the southwest coast of the Isle of Wight. Decades later, it was rediscovered in an old box, unclassified and forgotten, in the Carisbrooke Castle.

Two snout fragments found in the Aptian of Niger, Africa may have been Baryonyx. A tooth crown from east Sussex, another from Surrey, and seven from the Isle of Wight could also be Baryonyx.

Characteristics

            Although the only fairly complete specimen of Baryonyx is a juvenile (9.5 meters long and 3.6 meters tall) due to the undeveloped skull bones (not fused). Estimates can be made to decide its length as an adult. A fair estimate is 11.7 meters but 12 meters is possible.

The claws of Baryonyx are probably its most astonishing feature. Each one was about 35 centimeters long, nearly curved to a half circle and could have been used as a hook for grappling fish and other pray. These claws are not the only feature that suggests that Baryonyx ate fish. Its jaws are exceptionally crocodile-like as will be discussed below.

Baryonyx teeth are, unlike most other theropods, sharp and pointed at the tips. They are not serrated at the edges like other carnivorous dinosaurs. Instead, they are smooth, not unlike the modern crocodiles.

Although the primary diet of crocodiles, alligators, grails, and caimans is fish, they also eat land animals that come to drink or enter the water that they dwell in. I would presume, then, that Baryonyx did the much same thing. It would have been opportunistic; preying mainly on fish, but it would not hesitate to view any other animal that crossed its path potential pray in addition to fish. Baryonyx also had a bulbous at the end of its upper jaw (minimal in comparison to that of the crocodilian, the grail, but still a bulbous and a bit of a hook none the less) used, likely, for keeping slippery fish from sliding out of the jaws. It also had nostrils farther away from the end of the snout, enabling it has its jaws underwater for prolonged periods of time.

This suggest, fairly strongly, that Baryonyx feeding habits where very similar to that of the grail. Later, researcher Emily Rayfield used X-rays to create a computer model of the skull of Baryonyx. The results revealed that, not only did Baryonyx have a head that looked like a crocodile; it also bent and stretched like one. It would have been very good at resisting becoming mangled (minimizing the chance of injury while clinging to squirming prey) and maneuvering quickly to catch fast moving prey.

Turning back to the fossils themselves, rather than speculating from computer models, we find that they point to the same conclusion. In the stomach of the BMNH R9951 specimen there was found the remains of a fish, belonging to the genus Lepidotes. This practically tells us directly that Baryonyx was a piscivorous (fish-eater). But don’t jump to a conclusion. Along with the fish remains there was revealed pieces of a juvenile Iguanodon (an ornithopod dinosaur). So, although having a diet mainly of fish Baryonyx was also an opportunist, feeding on anything it could find. That is what I would conclude.

Another not-so-crocodilian feature is a small crest or horn just in front of, and between, the dinosaur’s eyes.

Comments

The dinosaur’s Genus, Baryonyx, means ‘heavy claw’ (Greek ‘baros’ meaning heavy and ‘onyx’ meaning claw or nail). This is obviously in reference to the large claw positioned on its slightly longer than would be expected arm (that is, in comparison to other large theropods). The species title was given in honor of its discoverer, Bill Walker. So came about the name of Baryonyx walkeri.

We will never know exactly what Baryonyx was like in life, but dragon sightings and descriptions, as well as paleontology, can tell us enough to spur our imaginations onward. That’s what paleontology is all about.

Baryonyx lapparenti

            This is the scratchiest of the Baryonyx species because of its fragmentary remains.

Classification

          I have decided to bunch this dinosaur into the Genus Baryonyx. Originally called Cristatusaurus lapparenti, many now consider it to be a synonym to Baryonyx.

Discovery

B. lapparenti was described by Taquet and Russell in 1998 on the bases of jaw fragments from two individuals (MHN GDF 366 and MHN GDF 365) discovered in Morocco in 1973. These are now located in the Heorg-August University in Gottingen, Germany. Although not much can be said from a few jaw fragments, they are incredibly similar to B. tenerensis and B. walkeri.

Characteristics

I have heard the estimate of eight to ten meters and twenty-five hundred to thirty-four hundred kilograms, but its skull was less than half the size of B. walkeri and was a lot smaller. Along with B. walkeri, it was probably a juvenile.

It was originally thought to have a horn or crest protruding from the snout but this was later found to be part of the jaw that had been crushed and broken to protrude outward; looking much like horn. It did, however, have a small crest between the eyes along with all spinosaurs.

Comments

            I have really said very little about B. lapparenti because of a lack of fossil evidence and hopefully the future will bring some new discoveries.

Cristatusaurus means ‘crested lizard’ because of the bone that was though to have jutted out like a horn from the snout. It is still a nice name, though, you have to admit. ‘Cristatusaurus’; say it out loud. ‘Cristatusaurus’.

Coming soon: Baryonyx tenerensis

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