Gigantic Pterosaur from the Nemegt Formation of Mongolia

An international team of scientists writing in the “Journal of Vertebrate Paleontology” have described the fragmentary neck bones of a gigantic pterosaur which might turn out to be one of the largest flying reptiles known to science.

It seems apt on “All Hallows’ Eve” to write about a creature, that if it was still around today, would be the stuff of nightmares.  The researchers, which include scientists from Tokyo University, Ohio University, the University of Pennsylvania as well as the Mongolian Academy of Sciences, estimate that the reptile could have had a wingspan in excess of 11 metres, perhaps even bigger.

An Azhdarchid Pterosaur – The Stuff of Nightmares

A model of the giant pterosaur Quetzalcoatlus.

The image (above) shows a replica of the giant azhdarchid pterosaur Quetzalcoatlus. This model features in the Safari Ltd model range.

To view this range: Wild Safari Prehistoric World Dinosaurs and Pterosaurs.

Fragmentary Fossil Evidence

The fragmentary fossils were found in 2006, during a field expedition to the western Gobi Desert to explore a fossil-rich series of sediments known as Gurilin Tsav.  Field team member and co-author of the scientific paper, Buuvei Mainbayar (Mongolian Academy of Sciences) found the first piece of a cervical vertebrae and showed it colleague Takanobu Tsuihiji (Tokyo University), who is the lead author of the paper.  More pieces of neck bone were found, but such was their fragmentary nature that it has taken more than a decade to complete an identification and publish data.

The bones have been assigned to an azhdarchid pterosaur.  The deposits around Gurilin Tsav date from the Upper Campanian to the Maastrichtian faunal stage of the Late Cretaceous.  These fossils represent the first azhdarchid fossils to have been found in the Nemegt Formation, in fact these are the first reported Pterosaur remains from this famous Formation.

A comparison between these fossilised neck bones and those of other, slightly better-known members of the Late Cretaceous pterosaur family known as the Azhdarchidae, indicate that the fossil material represents a “giant amongst giants”.   One of the neck bones measures nearly 20 centimetres in diameter, this is nearly four times as wide as the equivalent bone found in the huge azhdarchid pterosaur from the Late Cretaceous of Jordan (Arambourgiania).

The Azhdarchid Pterosaurs

It is not known whether this, as yet unnamed pterosaur had an exceptionally, thick, strong neck or whether the rest of its skeleton was much bigger than the likes of Hatzegopteryx or Quetzalcoatlus, hopefully, more fossils will be found.  This discovery provides further evidence that the Azhdarchidae were widely distributed across North America, Europe and Asia around 70 million years ago – not surprising really as these aerial giants would have been capable of flying incredibly long distances.

A Scale Drawing of the Giant Azhdarchid Pterosaur from Transylvania Hatzetgopteryx thambema

Hatzegopteryx – giant pterosaur from southern Europe.

Picture credit: Everything Dinosaur

The scientific paper: “Gigantic Pterosaurian remains from the Upper Cretaceous of Mongolia” by Tsuihiji, T., B. Andres, P. M. O’Connor, M. Watabe, K. Tsogtbaatar, and B. Mainbayar published in the Journal of Vertebrate Paleontology.

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Dinosaur Had Bandit Mask-like Stripe Across Its Eyes

Researchers from Bristol University have revealed how a small, feathered, compsognathid dinosaur used its colour patterning, including a bandit mask-like stripe across its eyes, to avoid being detected by its predators and prey.  This research has also allowed the authors of the scientific paper, published this week in “Current Biology”, to infer the sort of habitat that this little dinosaur might have lived in.

Once thought of being part of the fauna of the forest, it seems that Sinosauropteryx (S. prima), might have favoured more open environments.

An Illustration of Sinosauropteryx (S. prima) Hunting in an Open Environment

An illustration of Sinosauropteryx with its countershading and “bandit mask”.

Picture credit: Bob Nicholls

In the image created by Bob Nicholls (above), Sinosauropteryx is shown in an open habitat and it has just captured a lizard (Dalinghosaurus).

Multiple Types of Camouflage

Analysis of the preserved melanosomes enabled the team to reconstruct the likely colour patterning of this one-metre-long dinosaur.  The scientists conclude that Sinosauropteryx had multiple types of camouflage which helped it keep hidden from its prey as well as assisting in the avoidance of detection by much larger theropods and other predators.  The authors of the paper include corresponding author Jakob Vinther, Innes C. Cuthill, Fiann Smithwick from Bristol University as well as palaeoartist Bob Nicholls.

Fiann (School of Earth Sciences) stated:

“Far from all being the lumbering prehistoric grey beasts of past children’s books, at least some dinosaurs showed sophisticated colour patterns to hide from and confuse predators, just like today’s animals.”

Sinosauropteryx Fossil Specimen and Accompanying Line Drawing Showing Shading

Sinosauropteryx fossil material and line drawing (scale bar = 5 cm).

Picture credit: Bristol University

He went onto add:

“Vision was likely very important in dinosaurs, just like today’s birds, and so it is not surprising that they evolved elaborate colour patterns.”

Mapping Melanosomes and Comparative Anatomy

The study involved plotting how the dark pigmented feathers were distributed across the dinosaur’s body and then this pattern was compared to the patterns seen in extant animals and from this the optimum habitat to best maximise the camouflage was inferred.  Similar countershading patterns are found in many living animals and birds today.  The “bandit mask”, the dark stripe around the eye, is found in badgers, raccoons, red pandas and in birds such as the shrike.

In animals such as raccoons and badgers, the “bandit mask” acts as a warning, it advertises the fact that these animals are aggressive with teeth and claws that could cause considerable damage if another animal attacked them.  The research team discount this reason for Sinosauropteryx’s “Lone Ranger mask”, as an Everything Dinosaur team member calls it, Sinosauropteryx probably relied on its speed to avoid predation, it did not have very big teeth or strong claws required to back up such a visual statement.  The more likely reason for the bandit mask might be that it helped reduce glare from light reflected on feathers around the eye, just like in some modern birds.

Many sports stars such as American footballers and cricketers apply black greasepaint underneath their eyes.  It is believed to lessen the effect of the glare from direct sunlight or from stadium lights.  It helps them to see better, the “bandit mask” of Sinosauropteryx may have helped it to see better in bright sunlight.   This idea supports the view that Sinosauropteryx was a creature of open, brightly lit habitats.

An Illustration of Sinosauropteryx Sporting its “Bandit Mask”

Schematic illustration based on the distribution of pigmented plumage in two specimens highlighting the level of the countershading transition from a dark back to light underbelly, scale bar represents 10 cm.

Picture credit: Bristol University

Lead author, Dr Jakob Vinther, commented:

“Dinosaurs might be weird in our eyes, but their colour patterns very much resemble modern counterparts.  They had excellent vision, were fierce predators and would have evolved camouflage patterns like we see in living mammals and birds.”

A Dark Back and Light Underside – Countershading in the Dinosauria

The small dinosaur also showed a ‘counter-shaded’ pattern with a dark back and light belly; a pattern used by many modern animals to make the body look flatter and less three-dimensional.  This helps to prevent animals standing out from their background, making them harder to see, assisting in the avoidance of detection by would-be predators and potential prey.

Previous work on modern animals, carried out by one of the authors, Bristol’s Professor Innes Cuthill, has shown that the precise pattern of countershading relates to the specific environments in which animals live.  Animals living in open habitats, such as grasslands and plains, often have a countershaded pattern that goes from dark to light sharply and high on the side of the body, while those living in more closed habitats, arboreal habitats like forests, usually show a more gradual change in the colouration from a dark back to a lighter underside.

This idea was applied to Sinosauropteryx, and allowed for the reconstruction of its habitat 130 million years ago.  As part of the Jehol Biota, Sinosauropteryx was believed to have lived in a forested environment, but the countershading on Sinosauropteryx went from dark to light high on the body, suggesting that it would be more likely to live in open habitats with minimal vegetation.

Predicting the Countershading Pattern and Inferring the Habitat

3-D models of the abdomen countershading predicted following an assessment of pigmentation from two fossil specimens. (NIGP 127586 and NIGP 127587).

Picture credit: Bristol University

The Differing Pattern of Predicted Self-Shadowing in Sinosauropteryx

The picture above shows three-dimensional models of the abdomen of two fossil specimens of Sinosauropteryx involved in the study (NIGP 127586 and NIGP 127587).  These fossils were imaged under different lighting conditions. “Model” represents the original photographs taken of the models to show how the self-shadows are cast across each, with and without synthetic fur added to mimic the impact of a coat of feathers.  “Prediction” shows how a gradient of pigment dorsoventrally (from the back down the flank to the underbelly), would be expected to perfectly counterbalance the illumination gradient caused by self-shadowing.

(A and B) = direct sunlight at an altitude of around 30° on smooth and “feathered” models.

(C and D) = direct sunlight at an altitude of 90° on smooth and “feathered” models.

(E and F) = diffuse lighting under 100% cloud cover (which equates to a closed environment, such as a forest) on smooth and “feathered” models.

Studying Countershading

The ventral position and sharpness of the predicted countershading transition can be seen to be higher and sharper under overhead direct lighting, indicative of an open environment (C and D), whereas under diffuse lighting, representing a closed habitat, the transition is lower and more gradual (E and F).

In countershaded animals the top surface (back) is darker and the lower surface (underside) is lighter.  This helps to even out the effect of shadowing caused by sunlight, so countershaded animals appear less three-dimensional, helping the animal to avoid detection by predators and to assist it in sneaking up on its prey.  Crucially, lighting conditions vary depending on the environment.

Animals living in open areas with lots of light, such as grasslands, tend to have a sharp dark to light transition high up on the body, whereas in contrast, animals living in areas with less direct sunlight, such as wooded areas, tend to have more gradual transitions positioned lower down.  This means that the research team could infer the likely habitat of Sinosauropteryx based on the pattern of its countershading.

Three-dimensional models of the dinosaur’s body were made in a bid to determine in which environment the countershading pattern seen on Sinosauropteryx would be most effective.  The models were photographed in varying light conditions and the shadowing observed, the team then compared these results to the actual countershading pattern detected in the fossils.  They determined that the countershading transition for Sinosauropteryx was abrupt and it occurred high up on the flank, the best position to minimise the effect of shadows cast by direct sunlight.  It could therefore be inferred that Sinosauropteryx was best suited to an open environment.

A Model of Sinosauropteryx

PNSO Yuyan the Sinosauropteryx dinosaur model.

The picture (above) shows a model of Sinosauropteryx in the PNSO model series.

To view this range: PNSO Age of Dinosaurs Models and Figures.

This study provides a new insight into the lives and behaviour of members of the Dinosauria helping to reconstruct the long-lost habitats in which they lived.

Co-author of the study, Professor Innes Cuthill, a behavioural ecologist commented:

“We’ve shown before that countershading can act as effective camouflage against living predators.  It’s exciting that we can now use the colours of extinct animals to predict the sort of environment they lived in.”

Fiann Smithwick added:

“By reconstructing the colour of these long-extinct dinosaurs, we have gained a better understanding of not only how they behaved and possible predator-prey dynamics, but also the environments in which they lived.  This highlights how palaeocolour reconstructions can tell us things not possible from looking at just the bones of these animals.”

Everything Dinosaur acknowledges the help of the University of Bristol in the compilation of this article.

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New Ornithopod Dinosaur Described with Scissor-like Teeth

French and Belgian scientists have described a new species of plant-eating dinosaur which had scissor-like teeth, just the sort of dentition required to help it tackle tough, woody plants.  The dinosaur has been named Matheronodon provincialis and assigned to the Rhabdodontidae family, ornithopods and part of the substantial and diverse Iguanodontia clade.  Think of M. provincialis being distantly related to Iguanodon, Muttaburrasaurus and Mantellisaurus.

Matheronodon provincialis

An Illustration of the Skull and Jaws of Matheronodon provincialis

Matheronodon provincialis illustrated.

Picture credit: Royal Belgian Institute of Sciences (Lukas Panzarin)

Fossil Jawbone and Teeth

Field teams have been exploring the Upper Cretaceous sediments of Velaux-La Bastide Neuve, which lies to the north-west of the French city of Marseille for more than twenty-five years.  This location has yielded numerous vertebrate fossils including dinosaurs, Pterosauria, crocodilians and turtles.  The rocks in this region are estimated to be around 70 million years old (Campanian faunal stage of the Late Cretaceous).  Field work carried out in 2009 and 2012 by the Royal Belgian Institute of Sciences found several scrappy and fragmentary ornithopod fossils including a right maxilla (upper jawbone) from a herbivore, estimated to have grown to around five metres in length.

The teeth in the jaw are oversized and few in number, especially when compared to the dental batteries associated with hadrosaurs.  In addition, the jaw is robust and indicates that Matheronodon had a powerful bite.

Writing in the academic journal “Scientific Reports”, the authors, which include Pascal Godefroit (Directorate Earth and History of Life, Royal Belgian Institute of Natural Sciences), state that Matheronodon is characterised by the large teeth found in the upper and lower jaws, as well as the drastic reduction in the number of maxillary teeth (just four per generation).

The Holotype Fossil Material for Matheronodon provincialis (Right Maxilla)

The right upper jawbone (maxilla) of Matheronodon.

Picture credit: Royal Belgian Institute of Sciences (Scientific Reports)

The picture above shows various views of the holotype fossil material, the right maxilla (MMS/VBN-02-102), (a) dorsal view, (b) lateral view, (c) medial view and (d) ventral view, with accompanying line drawings.  Picture (e) is a close-up of the ventral view of the jaw showing the enlarged teeth.  The researchers estimate that some of the individual teeth in the front portion of the maxilla were up to 6 cm long and 5 cm wide.

Honouring Philippe Matheron

The genus name honours the French 19th century palaeontologist Philippe Matheron, who named and described Rhabdodon (R. priscus), the dinosaur which lent its name to the Rhabdodontidae family.  Lead author of the paper Pascal Godefroit commented:

“The denture of this group [rhabdodontids] had evolved in a different direction than that of their contemporaries, the hadrosaurs or duck-billed dinosaurs.  Hadrosaurs had sophisticated dental “batteries” formed by little teeth with which they could crush conifers.  Matheronodon and the other Rhabdodontidae probably ate leaves of palm trees, which were abundant in Europe at that time.  They had to cut rather than crush the fibre-rich leaves, before they could swallow them.”

Cutting Palm Leaves – Playing the Role of the Ceratopsians

Matheronodon might have specialised in eating tough plant matter, plants such as Sabalites and Pandanites sp. which were abundant in the area during the Late Cretaceous.  The teeth and jaws are described as “operating like self-sharpening serrated scissors”, the teeth have ridged surfaces but are covered with a thickened enamel layer on one side, as the jaw moves up and down, the side of the tooth with the thicker enamel resists wear more effectively than the dentine as it is exposed.  As a result, the movement of the jaws as the animal chews, keeps the teeth sharp.

A Fossilised Palm Frond (Sabalites sp.) Green River Formation

A fossil palm frond from Wyoming (most likely). Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Horned dinosaurs (ceratopsians) are relatively abundant in similarly aged deposits from North America, in contrast, rhabdodontids have not be found.  The researchers suggest that in Europe dinosaurs like Matheronodon filled the niche occupied by the horned dinosaurs, as, although there have been accounts of Ceratopsian fossil discoveries in Europe, these fossils are very rare, indicating that horned dinosaurs only made up a tiny proportion of the total dinosaur biota.  Ceratopsians and rhabdodontids probably competed for the same food resources, specialising in the consumption of tough, woody material such as palm leaves, an example of which from the Eocene Epoch (Sabalites sp.), is shown above.

The scientific paper: “Extreme Tooth Enlargement in a New Late Cretaceous rhabdodontid Dinosaur from Southern France” by Pascal Godefroit, Géraldine Garcia, Bernard Gomez, Koen Stein, Aude Cincotta, Ulysse Lefèvre and Xavier Valentin, published in the on-line, open access journal “Scientific Reports.”

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India Has Its First Ichthyosaur

What has Dorset and New Delhi got in common?  What’s the connection between Charmouth and Gujarat State?  It seems that marine reptiles are the link, with the discovery of India’s first ichthyosaur fossil.  Granted, the Indian ichthyosaur is younger than the ichthyosaur material related with Lyme Regis and Charmouth but just as palaeontologists from the Dorset Museum have excavated ichthyosaur fossils, so have their counterparts from Delhi University.  Intriguingly, these may be the first ichthyosaur fossils to have been found in Gujarat State, but they won’t be the last, there are very probably lots more ichthyosaur (and plesiosaur) fossils awaiting discovery in India’s most westerly State.

Ichthyosaur Fossils Found In India

A Field Photograph Showing the Fossil Material and Accompanying Line Drawing

A photograph showing the Ichthyosaur fossil as it is exposed, with line drawing (below).

Picture credit:  Dr Guntupalli V.R. Prasad (University of Delhi)

Member of the Ophthalmosauridae

Writing in journal PLOS One, the researchers conclude that the partial 3.6-metre-long fossil represents the remains of an ichthyosaur that measured between 5 and 5.5 metres in length.

The specimen was discovered in the greenish-yellow shales of the Katrol Formation exposed at a site just south of the village of Lodai in the Kachchh district of Gujarat.  The presence of ammonites and belemnites (important zonal fossils), suggest that the ichthyosaur lived some 152 million years ago in the Kimmeridgian (there’s that Dorset connection again), faunal zone of the Late Jurassic.  The broken tips of the teeth, could have resulted from taphonomy but they might suggest that this marine reptile had a duraphagous diet, crunching the shells of ammonites.

For models of marine reptiles and ammonites: CollectA Prehistoric Life Models and Figures.

This new ichthyosaur species has yet to be formally named but it has been assigned to the Ophthalmosauridae, a family of ichthyosaurs that were widespread in the Late Jurassic.

Wear on the Teeth and Broken Teeth Suggest a Diet of Hard-shelled Creatures Such as Ammonites

Views of two teeth from the Indian Ichthyosaur (scale bar = 1 cm).

Picture credit: PLOS One

Commenting on the discovery, lead author, Dr Guntupalli V. R. Prasad (University of Delhi) stated:

“This is a remarkable discovery not only because it is the first Jurassic ichthyosaur record from India, but also it throws light on the evolution and diversity of ichthyosaurs in the Indo-Madagascan region of the former Gondwanaland and India’s biological connectivity with other continents in the Jurassic.”

Faunal Exchanges

The research team conclude that the widespread occurrence of ophthalmosaurids in the Upper Jurassic deposits of western Tethys, Madagascar, South America and India indicate possible faunal exchanges between the western Tethys and Gondwanan continents through a southern seaway.

A Photograph and Line Drawing of the Left Forefin

The left forefin and accompanying line drawing of the Indian ichthyosaur.

Picture credit: PLOS One

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