A scientific paper has just been published in the open-access journal PLOS ONE that describes a new species of giant ichthyosaur. This huge marine reptile, named Ichthyotitan severnensis could have been about as big as a blue whale (Balaenoptera musculus).  The discovery of the fragmentary remains of a second gigantic jawbone in Somerset supports the hypothesis that giant ichthyosaurs were present in the Late Triassic ecosystem.

A washed-up Ichthyotitan severnensis carcase on the beach being visited by two hungry theropod dinosaurs and a flock of curious pterosaurs. Picture credit: Sergey Krasovskiy.

Giant Ichthyosaurs from Somerset

Fossil collector and co-author of this study Paul de la Salle, found a portion of fossil jaw in May 2016. He later returned to the location (the beach at Lilstock, west Somerset) and found more pieces that together formed a partial surangular more than a metre in length.  The second fragmentary jawbone, also a surangular was found on a beach a few miles to the east of the original fossil discovery.

In May 2020, Father and daughter, Justin and Ruby Reynolds from Braunton, Devon found the first pieces of the second surangular.  They were fossil hunting on the beach at Blue Anchor. Ruby, then aged eleven found the first chunk of fossil bone and went onto to find several more fragments.

Realising that Ruby may have discovered something of considerable scientific value, the family contacted leading ichthyosaur expert, Dr Dean Lomax, a palaeontologist at The University of Manchester. Dr Lomax, who is also a 1851 Research Fellow at the University of Bristol, contacted Paul de la Salle as he recognised the striking similarity between the two fossil finds.

Dr Dean Lomax commented:

“I was amazed by the find. In 2018, my team (including Paul de la Salle) studied and described Paul’s giant jawbone and we had hoped that one day another would come to light. This new specimen is more complete, better preserved, and shows that we now have two of these giant bones – called a surangular – that have a unique shape and structure. I became very excited, to say the least.”

Photograph of the nearly complete giant jawbone (surangular), along with a comparison with the 2018 bone (middle and bottom) found by Paul de la Salle. Picture credit: Dr Dean Lomax.

Hunting for More Fossil Evidence

Justin and Ruby, together with Paul, Dr Lomax, and several family members, visited the site to hunt for more pieces of fossil bone. Over time, the team found additional fragments of the same jaw which fit together perfectly, like a multimillion-year-old ichthyosaur jigsaw.

Father Justin explained:

“When Ruby and I found the first two pieces we were very excited as we realised that this was something important and unusual. When I found the back part of the jaw, I was thrilled because that is one of the defining parts of Paul’s earlier discovery.”

The last piece of bone was recovered in October 2022.

Part of the research team in 2020 examining the initial finds (at the back) of the new discovery made by Ruby and Justin Reynolds. Additional sections of the bone were subsequently discovered. From left to right, Dr Dean Lomax, Ruby Reynolds, Justin Reynolds and Paul de la Salle. Picture credit: Dr Dean Lomax.

Ichthyotitan severnensis

Lead author of the study, Dr Lomax commented that the jaw fossils belong to a new species of enormous ichthyosaur.  It would have measured perhaps as much as twenty-five metres in length.  Ichthyotitan severnensis was probably larger than any extant toothed whale.  Based on comparisons with better known shastasaurid ichthyosaurs, it could have been as big as a blue whale.  Analysis of the geology of the two fossil sites along with a detailed comparison of the two surangular fossils supports the team’s hypothesis that these fossils represent an enormous ichthyosaur that is new to science.

An Ichthyotitan severnensis scale drawing. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The genus and species name translates as “giant fish lizard of the Severn”.

The fossil material is estimated to be around 202 million years old, dating to the end of the Triassic (Rhaetian faunal stage).  Gigantic ichthyosaurs (Shastasauridae) swam in the seas while the Dinosauria were beginning to dominate terrestrial environments.  Ichthyotitan was one of the last of the shastasaurids, these Somerset fossils represent the last of their kind.  The Shastasauridae family are thought to have become extinct at the end of the Triassic.

Ichthyotitan severnensis was not the world’s first giant marine reptile, but de la Salles’ and Reynolds’ discoveries are unique among those known to science. These two bones appear to be approximately thirteen million years younger than their latest geologic relatives, including Shonisaurus sikanniensis (British Columbia, Canada), and Himalayasaurus tibetensis from Tibet, China.

Dr Lomax added:

“I was highly impressed that Ruby and Justin correctly identified the discovery as another enormous jawbone from an ichthyosaur. They recognised that it matched the one we described in 2018. I asked them whether they would like to join my team to study and describe this fossil, including naming it. They jumped at the chance. For Ruby, especially, she is now a published scientist who not only found but also helped to name a type of gigantic prehistoric reptile. There are probably not many 15-year-olds who can say that! A Mary Anning in the making, perhaps.”

Ruby exclaimed:

“It was so cool to discover part of this gigantic ichthyosaur. I am very proud to have played a part in a scientific discovery like this.”

A giant pair of swimming Ichthyotitan severnensis. Picture credit: Gabriel Ugueto.

Not Yet Fully Grown

Further examinations of the bones’ internal structures have been carried out by master’s student, Marcello Perillo, from the University of Bonn, Germany. His research confirmed the ichthyosaur origin of the bones and also revealed that the animal was still growing at the time of death.

He said:

“We could confirm the unique set of histological characters typical of giant ichthyosaur lower jaws: the anomalous periosteal growth of these bones hints at yet to be understood bone developmental strategies, now lost in the deep time, that likely allowed Late Triassic ichthyosaurs to reach the known biological limits of vertebrates in terms of size. So much about these giants is still shrouded by mystery, but one fossil at a time we will be able to unravel their secret.”

Concluding the work, Paul de la Salle added:

“To think that my discovery in 2016 would spark so much interest in these enormous creatures fills me with joy. When I found the first jawbone, I knew it was something special. To have a second that confirms our findings is incredible. I am overjoyed.”

Ichthyotitan severnensis Fossils on Public Display

The fossilised remains will soon be put on display at the Bristol Museum and Art Gallery (Bristol).

Dr Lomax summarised the study:

“This research has been ongoing for almost eight years. It is quite remarkable to think that gigantic, blue whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period. These jawbones provide tantalising evidence that perhaps one day a complete skull or skeleton of one of these giants might be found. You never know.”

To read Everything Dinosaur’s 2018 article about the first surangular fossil discovery: Late Triassic Giant Ichthyosaurs.

Everything Dinosaur acknowledges the assistance of a media release from the University of Manchester in the compilation of this article.

The scientific paper “The last giants: New evidence for giant Late Triassic (Rhaetian) ichthyosaurs from the UK” by Lomax D. R., de la Salle, P., Perillo, M., Reynolds, J., Reynolds, R. and Waldron, J. F. published in PLOS ONE.

Visit the website of Dr Dean Lomax: British Palaeontologist Dr Dean Lomax.

Twelve new Australian sauropods have been classified following a comprehensive reassessment of Winton Formation fossil remains.  Twelve new sauropod fossil specimens from the Winton Formation (Queensland, Australia) have been described. The extensive review, which involved CT scanning hundreds of fossil bones, has resolved the known sauropods from the Winton Formation into three distinct taxa.

Assessment of Twelve New Australian Sauropods Confirms Three Taxa

The taxa are Diamantinasaurus matildae, Savannasaurus elliottorum and Wintonotitan wattsi. A fourth sauropod, Australotitan cooperensis is now considered an indeterminate diamantinasaurian. The review suggests that the material previously assigned to A. cooperensis might represent a Diamantinasaurus. If this is the case, then Diamantinasaurus was capable of growing much larger than earlier studies indicated. A. cooperensis may become nomen dubium (dubious scientific name not widely recognised).

PhD candidate Samantha Beeston scanning Diamantinasaurus fossil material.  Picture credit: Australian Age of Dinosaurs Museum of Natural History.

Picture credit: Australian Age of Dinosaurs Museum of Natural History

The ground-breaking study into these enormous, ground-shaking dinosaurs was led by University of College London PhD candidate Samantha Beeston in collaboration with the Australian Age of Dinosaurs Museum of Natural History. Beeston’s research was conducted as part of her Master’s thesis at Swinburne University of Technology, under the supervision of Dr Stephen Poropat (now at the Western Australian Organic and Isotope Geochemistry Centre, Curtin University). The paper has been published in the open-access journal PeerJ.

A life reconstruction of Australotitan cooperensis, the largest known animal to have ever lived in Australia. A reassessment of the fossilised bones suggests that A. cooperensis might be nomen dubium as the fossil remains could represent a very large specimen of Diamantinasaurus matildae.  Picture credit: Queensland Museum.

Picture credit: Queensland Museum

To read an earlier blog article (2015) about titanosaur fossil remains later named A. cooperensis awaiting scientific description: Super-sized Aussie Titanosaur Awaits Scientific Description.

A sauropod excavation site photographed in 2011.  Picture credit: Australian Age of Dinosaurs Museum of Natural History.

Picture credit: Australian Age of Dinosaurs Museum of Natural History

Three Australian Sauropods

The researchers were able to assign two new specimens to Diamantinasaurus matildae. In addition, two specimens were assigned to Savannasaurus elliottorum with three more being assigned to Wintonotitan wattsi. The other five specimens are too incomplete to classify at the genus level. They have been described as indeterminate diamantinasaurians.  A lack of comparable specimens with overlapping bones has hampered precise classification of these five specimens.

The three recognised Winton Formation sauropod taxa are:

• Diamantinasaurus matildae – named in 2009 (Hocknull et al).
• Savannasaurus elliottorum – named in 2016 (Poropat et al).
• Wintonotitan wattsi – named in 2009 in the same scientific paper as D. matildae and the theropod Australovenator wintonensis (Hocknull et al).
  

Over five hundred sauropod bones were scanned as part of this research. This innovative approach enabled the scientists to evaluate each bone and compare it to other fossil specimens in the Museum’s extensive collection. The study has led to a better understanding of the unique traits that help to separate known species.  Student Samantha Beeston explained that as there are so few bones preserved for Australotitan it makes it very difficult, if not impossible to assign new specimens to it, or to differentiate it from any of the other Winton Formation sauropod taxa.

She added: “Due to the limited fossil evidence for Australotitan, resolving its classification will be challenging.”

Student Samantha Beeston scanning the toe bone of Diamantinasaurus.  Picture credit: Australian Age of Dinosaurs Museum of Natural History.

Picture credit: Australian Age of Dinosaurs Museum of Natural History

Significant for Australian Palaeontology

David Elliott, the Executive Chairman of the Australian Age of Dinosaurs Museum of Natural History commented that he was delighted to have more sauropod specimens in the Museum’s collection assigned to distinct species. He explained that having a better understanding of autapomorphies and anatomical traits leading to more confident assignment of taxa was a significant leap forward in Australian palaeontological research.  The twelve new Australian sauropods would provide the basis for further research into the dinosaurs of the Winton Formation.

He added:

“These dinosaurs help demonstrate the diverse natural history of Australia during the Cretaceous Period and will become important exhibits at the new Australian Age of Dinosaurs Museum of Natural History.”

Volunteers work at the “Devil Dave” sauropod excavation site (2017).  Picture credit: Australian Age of Dinosaurs Museum of Natural History.

Picture credit: Australian Age of Dinosaurs Museum of Natural History

Everything Dinosaur acknowledges the assistance of a media release from the Australia Age of Dinosaurs Museum of Natural History in the compilation of this article.

The scientific paper: “Reappraisal of sauropod dinosaur diversity in the Upper Cretaceous Winton Formation of Queensland, Australia, through 3D digitisation and description of new specimens” by Samantha L. Beeston​, Stephen F. Poropat, Philip D. Mannion, Adele H. Pentland, Mackenzie J. Enchelmaier, Trish Sloan and David A. Elliott published in PeerJ.

The Everything Dinosaur website: Dinosaur Models and Toys.

Evidence of a Devonian fossil forest has been found in the high sandstone cliffs located near Minehead in Devon. Researchers from the University of Cambridge and the University of Cardiff have discovered the oldest fossilised trees ever found in the UK. The fossil remains of the trees, known as Calamophyton represent the oldest known fossil forest on Earth.

Fossilised tree stumps near the town of Gilboa (New York, USA) and a quarry at nearby Cairo, New York are thought to be 380 and 385 million years old respectively. The Gilboa site is dominated by remains of Wattieza trees. These trees are related to the Calamophyton trees identified at the Devon site. They are both members of the Pseudosporochnales Order and are distantly related to modern ferns.

Devonian Fossil Forest

The Devonian fossil forest is thought to be around four million years older than the tree fossils discovered in New York. The forest is approximately 390 million years old (Eifelian faunal stage of the Middle Devonian).

The fossils were found near the town of Minehead. The site is located on the south bank of the Bristol Channel, near a Butlin’s holiday camp. The fossilised trees, known as Calamophyton, at first glance resemble palm trees, but they are not related to modern angiosperms. Rather than solid wood, their trunks were thin and hollow in the centre. They also lacked leaves, and their branches were covered in hundreds of twig-like structures.

Evidence of Arthropods Found

The trees were much shorter than extant trees. The largest specimens were between two and four metres high. As the trees grew, they shed their branches. The floor of the forest was covered in a dense mat of decaying vegetation. This was home to an array of invertebrates and arthropod tracks have been discovered at this site.

A Devonian Ecosystem

It had been thought that these sandstone cliffs were largely devoid of fossils. This remarkable discovery demonstrates how early trees helped to stabilise riverbanks and coastlines hundreds of millions of years ago. It was during the Devonian that the first extensive terrestrial forests formed.

The Devonian lasted between 419 million and 359 million years ago. During this geological period the first complex terrestrial ecosystems evolved. By the end of the Devonian, the first seed-bearing plants (pteridosperms) appeared and the earliest land animals, mostly arthropods, were well-established.

Fundamentally Changing Life on Earth

Commenting on the significance of the fossil forest discovery, one of the paper’s co-authors, Professor Neil Davies (Cambridge University), stated:

“The Devonian period fundamentally changed life on Earth. It also changed how water and land interacted with each other, since trees and other plants helped stabilise sediment through their root systems, but little is known about the very earliest forests.”

The Devonian fossil forest identified by the researchers was found in the Hangman Sandstone Formation, along the north Devon and west Somerset coasts. During the Devonian period, this region was not attached to the rest of England, but instead lay further south, connected to parts of Germany and Belgium, where similar Devonian fossils have been found.

Studying the Ecology of the Earliest Forests on Earth

Co-author Dr Christopher Berry (Cardiff University) commented:

“When I first saw pictures of the tree trunks I immediately knew what they were, based on 30 years of studying this type of tree worldwide. It was amazing to see them so near to home. But the most revealing insight comes from seeing, for the first time, these trees in the positions where they grew. It is our first opportunity to look directly at the ecology of this earliest type of forest, to interpret the environment in which Calamophyton trees were growing, and to evaluate their impact on the sedimentary system.”

During the Devonian, this location was a semi-arid plain, criss-crossed by small river channels spilling out from mountains to the northwest. The fieldwork was undertaken along the highest sea-cliffs in England, some of which are only accessible by boat. The sandstone formation is in fact rich with plant fossil material. The researchers identified fossilised plants and plant debris, fossilised tree logs, traces of roots and sedimentary structures, preserved within the sandstone.

A Weird Forest

Professor Davies explained:

“This was a pretty weird forest – not like any forest you would see today. There wasn’t any undergrowth to speak of and grass hadn’t yet appeared, but there were lots of twigs dropped by these densely-packed trees, which had a big effect on the landscape.”

This was the first time in the history of our planet that large plants could grow together on land. The sheer abundance of debris shed by the Calamophyton trees built up within layers of sediment. The sediment affected the way that the rivers flowed across the landscape, the first time that the course of rivers could be affected in this way.

Professor Davies added:

“The evidence contained in these fossils preserves a key stage in Earth’s development, when rivers started to operate in a fundamentally different way than they had before, becoming the great erosive force they are today. People sometimes think that British rocks have been looked at enough, but this shows that revisiting them can yield important new discoveries.”

Everything Dinosaur acknowledges the assistance of a media release from the University of Cambridge in the compilation of this article.

The scientific paper: “Earth’s earliest forest: fossilized trees and vegetation-induced sedimentary structures from the Middle Devonian (Eifelian) Hangman Sandstone Formation, Somerset and Devon, SW England” by Neil S. Davies, William J. McMahon and Christopher M. Berry published in Journal of the Geological Society.

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A new mosasaur taxon from the Late Cretaceous of Morocco has been scientifically described. Khinjaria acuta was as long as an Orca (Orcinus orca). It had a robust skull, strong jaws and dagger-like teeth. The researchers contrast today’s marine ecosystems with few apex predators, with the Late Cretaceous marine environment. Writing in the journal “Cretaceous Research” the researchers portray an ancient marine ecosystem teeming with predators.

Khinjaria acuta

The study is based on a skull and parts of the postcranial skeleton collected from a phosphate mine southeast of Casablanca (Morocco). Researchers from the University of Bath, the Marrakech Museum of Natural History, the Museum National d’ Histoire Naturelle (NMNH) in Paris (France), Southern Methodist University in Texas (USA), and the University of the Basque Country (Bilbao) were involved.

Measuring around eight metres in length, Khinjaria used its long, dagger-like teeth to seize prey. It was part of an extraordinarily diverse fauna of predators that inhabited the Atlantic Ocean off the coast of Morocco during the Maastrichtian faunal stage of the Late Cretaceous.

The Sheer Diversity of Top Predators in the Marine Ecosystem

One of the authors of the scientific paper, Dr Nick Longrich (University of Bath), stated:

“What’s remarkable here is the sheer diversity of top predators. We have multiple species growing larger than a great white shark, and they’re top predators, but they all have different teeth, suggesting they’re hunting in different ways.”

Dr Longrich added:

“Some mosasaurs had teeth to pierce prey, others to cut, tear, or crush. Now we have Khinjaria, with a short face full of huge, dagger-shaped teeth. This is one of the most diverse marine faunas seen anywhere, at any time in history, and it existed just before the marine reptiles and the dinosaurs went extinct.”

A Diversity of Moroccan Marine Reptiles

Fossil discoveries have highlighted the astonishing diversity of large marine reptiles in the environment. Their different dentition suggests that many were not directly competing, that niche partitioning was occurring. For example, the researchers conducted a phylogenetic analysis and placed Khinjaria in a mosasaur clade which they named the Selmasaurini. Also placed in this clade was the Moroccan plioplatecarpine mosasaur Gavialimimus almaghribensis. This mosasaur was a specialised fish hunter.

To read Everything Dinosaur’s article about Gavialimimus almaghribensis: A New Species of Mosasaur from Morocco.

Mosasaurs, plesiosaurs and giant sea turtles disappeared, along with entire families of fish at the end of the Cretaceous. This led to the evolution of modern marine ecosystems with whales and seals as apex predators along with teleost fish such as swordfish and tuna.

Dr Longrich commented:

“There seems to have been a huge change in the ecosystem structure in the past 66 million years. This incredible diversity of top predators in the Late Cretaceous is unusual, and we don’t see that in modern marine communities.”

An Ecosystem Different from a Modern Marine Ecosystem

Modern marine food chains have just a few large apex predators, animals like orcas, white sharks, and leopard seals. The Late Cretaceous had many more types of marine predators.

Dr Longrich continued:

“Modern ecosystems have predators like baleen whales and dolphins that eat small prey, and not many things eating large prey. The Cretaceous has a huge number of marine reptile species that take large prey. Whether there’s something about marine reptiles that caused the ecosystem to be different, or the prey, or perhaps the environment, we don’t know. But this was an incredibly dangerous time to be a fish, a sea turtle, or even a marine reptile.”

Professor Nathalie Bardet, (Natural History Museum of Paris), explained:

“The Phosphates of Morocco deposit in a shallow and warm epicontinental sea, under a system of upwellings; these zones are caused by currents of deep, cold, nutrient-rich waters rising towards the surface, providing food for large numbers of sea creatures and, as a result, supporting a lot of predators. This is probably one of the explanations for this extraordinary paleobiodiversity observed in Morocco at the end of the Cretaceous.”.

The phosphate mines of Morocco have provided a wealth of marine fossil material. The specimens collected include the “saw-toothed” mosasaur Xenodens, Stelladens which had teeth with additional cutting edges and Thalassotitan whose teeth were conical in shape and massive.

Everything Dinosaur acknowledges the assistance of a media release from the University of Bath in the compilation of this article.

The scientific paper: “A bizarre new plioplatecarpine mosasaurid from the Maastrichtian of Morocco” by Nicholas R. Longrich, Michael J. Polcyn, Nour-Eddine Jalil, Xabier Pereda-Suberbiola and Nathalie Bardet published in Cretaceous Research.

Take a look at the Everything Dinosaur website: Everything Dinosaur.

A team of scientists have described new specimens of Dinocephalosaurus orientalis a bizarre, Triassic marine reptile. First scientifically described in 2003 (Li Chun), this new study has permitted scientists to construct the enormous neck of this animal in detail.

Measuring up to five metres in length, Dinocephalosaurus orientalis had an extremely long and flexible neck. The neck contains a total of thirty-two vertebrae. Tanystropheus in contrast, had thirteen cervical vertebrae. In some specimens the neck is 1.7 metres in length. It is much longer than the animal’s torso. The researchers compare D. orientalis to the Tanystropheus taxon. Tanystropheus is known from the Middle Triassic of Europe and China. Whilst Tanystropheus and Dinocephalosaurus had similar body shapes, these reptiles were not closely related. The long necks seen in these two taxa are an example of convergent evolution.

Dinocephalosaurus orientalis A Remarkable Marine Reptile

The scientific paper describing the animal is published in full in the academic journal Earth and Environmental Science: Transactions of the Royal Society of Edinburgh – forming the entirety of the latest volume.

Fellow of the Royal Society of Edinburgh and Editor-in-Chief of the RSE’s academic journal Transactions, Professor Robert Ellam FRSE commented:

“This remarkable marine reptile is another example of the stunning fossils that continue to be discovered in China”.

Comparisons with Tanystropheus

Both reptiles were of similar size and have several features of the skull in common, including a fish-trap type of dentition. However, Dinocephalosaurus is unique in possessing several more vertebrae both in the neck and in the torso, giving the animal a much more snake-like appearance. The neck of Dinocephalosaurus was more flexible than the neck of Tanystropheus. The fossils analysed in the newly published paper come from the Guizhou Province of China.

Dr Nick Fraser FRSE, Keeper of Natural Sciences at National Museums Scotland stated:

“This discovery allows us to see this remarkable long-necked animal in full for the very first time. It is yet one more example of the weird and wonderful world of the Triassic that continues to baffle palaeontologists. We are certain that it will capture imaginations across the globe due to its striking appearance, reminiscent of the long and snake-like, mythical Chinese Dragon.”

Appropriate for the “Year of the Dragon”

As we have now entered the Chinese “Year of the Dragon”, a new scientific paper on a Chinese reptile that superficially resembled a mythical dragon is highly appropriate. The fossils were studied over a period of ten years by researchers from Scotland, China, America and Germany.

Professor Li Chun from the Institute of Vertebrate Palaeontology and Palaeoanthropology in China, the scientist who originally described Dinocephalosaurus orientalis said:

“This has been an international effort. Working together with colleagues from the United States of America, the United Kingdom and Europe, we used newly discovered specimens housed at the Chinese Academy of Sciences to build on our existing knowledge of this animal. Among all of the extraordinary finds we have made in the Triassic of Guizhou Province, Dinocephalosaurus probably stands out as the most remarkable.”

Scientists propose that Dinocephalosaurus was superbly adapted to its marine environment. Given the length of its neck, moving on land would have been difficult. A remarkable fossil described in 2017 revealed that Dinocephalosaurus was viviparous (live birth). This remains the only record of viviparity associated with the Archosauromorpha.

To read Everything Dinosaur’s blog post about this discovery: First Evidence of Live Birth in Ancient Dinosaur Relative.

Dinocephalosaurus orientalis – Significant Fossil Discoveries

Dr Stephan Spiekman, a postdoctoral researcher based at the Stuttgart State Museum of Natural History, commented:

“As an early-career researcher, it has been an incredible experience to contribute to these significant findings. We hope that our future research will help us understand more about the evolution of this group of animals, and particularly how the elongate neck functioned.”

The paper describing the animal is published in full in the academic journal Earth and Environmental Science: Transactions of the Royal Society of Edinburgh – forming the entirety of the latest volume. The journal was first published in 1788.

Everything Dinosaur acknowledges the assistance of media releases from the Royal Society of Edinburgh and National Museums Scotland in the compilation of this article.

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