Researchers have discovered a huge new mosasaur from Morocco, named Thalassotitan atrox, which filled the apex predator niche. With massive jaws and teeth like those of killer whales, Thalassotitan hunted other marine reptiles — plesiosaurs, sea turtles, and other mosasaurs.

At the end of the Cretaceous period, 66 million years ago, sea monsters really existed. While dinosaurs flourished on land, the seas were ruled by the mosasaurs, giant marine reptiles.

Mosasaurs weren’t dinosaurs, but enormous marine lizards growing up to 12 metres (40 feet) in length. They were distant relatives of modern iguanas and monitor lizards.

Mosasaurs looked like a Komodo dragon with flippers instead of legs, and a shark-like tail fin. Mosasaurs became larger and more specialised in the last 25 million years of the Cretaceous, taking niches once filled by marine reptiles like plesiosaurs and ichthyosaurs. Some evolved to eat small prey like fish and squid. Others crushed ammonites and clams. The new mosasaur, named Thalassotitan atrox, evolved to prey on all the other marine reptiles.

The remains of the new species were dug up in Morocco, about an hour outside Casablanca. Here, near the end of the Cretaceous, the Atlantic flooded northern Africa. Nutrient rich waters upwelling from the depths fed blooms of plankton. Those fed small fish, feeding larger fish, which fed mosasaurs and plesiosaurs — and so on, with these marine reptiles becoming food for the giant, carnivorous Thalassotitan.

Thalassotitan, had an enormous skull measuring 1.4 metres (5 feet long), and grew to nearly 30 feet (9 metres) long, the size of a killer whale. While most mosasaurs had long jaws and slender teeth for catching fish, Thalassotitan had a short, wide muzzle and massive, conical teeth like those of an orca. These let it seize and rip apart huge prey. These adaptations suggest Thalassotitan was an apex predator, sitting at the top of the food chain. The giant mosasaur occupied the same ecological niche as today’s killer whales and great white sharks.

Thalassotitan’s teeth are often broken and worn, however eating fish wouldn’t have produced this sort of tooth wear. Instead, this suggests that the giant mosasaur attacked other marine reptiles, chipping, breaking, and grinding its teeth as it bit into their bones and tore them apart. Some teeth are so heavily damaged they have been almost ground down to the root.

Fossilised remains of prey

Remarkably, possible remains of Thalassotitan’s victims have been discovered. Fossils from the same beds show damage from acids, with teeth and bone eaten away. Fossils with this peculiar damage include large predatory fish, a sea turtle, a half-meter long plesiosaur head, and jaws and skulls of at least three different mosasaur species. They would have been digested in Thalassotitan’s stomach before it spat out their bones.

“It’s circumstantial evidence,” said Dr Nick Longrich, Senior Lecturer from the Milner Centre for Evolution at the University of Bath and lead author on the study, published in Cretaceous Research.

“We can’t say for certain which species of animal ate all these other mosasaurs. But we have the bones of marine reptiles killed and eaten by a large predator.

“And in the same location, we find Thalassotitan, a species that fits the profile of the killer — it’s a mosasaur specialised to prey on other marine reptiles. That’s probably not a coincidence.”

Thalassotitan was a threat to everything in the oceans — including other Thalassotitan. The huge mosasaurs bear injuries sustained in violent combat with other mosasaurs, with injuries to their face and jaws sustained in fights. Other mosasaurs show similar injuries, but in Thalassotitan these wounds were exceptionally common, suggesting frequent, intense fights over feeding grounds or mates.

“Thalassotitan was an amazing, terrifying animal,” said Dr Nick Longrich, who led the study. “Imagine a Komodo Dragon crossed with a great white shark crossed with a T. rex crossed with a killer whale.”

The new mosasaur lived in the final million years of the Age of Dinosaurs, a contemporary of animals like T. rex and Triceratops. Along with recent discoveries of mosasaurs from Morocco, it suggests that mosasaurs weren’t in decline before the asteroid impact that drove the Cretaceous mass extinction. Instead, they flourished.

Professor Nour-Eddine Jalil, a co-author on the paper from the Museum of Natural History in Paris, said: “The phosphate fossils of Morocco offer an unparalleled window on the paleobiodiversity at the end of Cretaceous.

“They tell us how life was rich and diversified just before the end of the ‘dinosaur era’, where animals had to specialise to have a place in their ecosystems. Thalassotitan completes the picture by taking on the role of the megapredator at the top of the food chain.”

“There’s so much more to be done,” said Longrich. “Morocco has one of the richest and most diverse marine faunas known from the Cretaceous. We’re just getting started understanding the diversity and the biology of the mosasaurs.”

Reference:
Nicholas R. Longrich, Nour-Eddine Jalil, Fatima Khaldoune, Oussama Khadiri Yazami, Xabier Pereda-Suberbiola, Nathalie Bardet. Thalassotitan atrox, a giant predatory mosasaurid (Squamata) from the Upper Maastrichtian Phosphates of Morocco. Cretaceous Research, 2022; 105315 DOI: 10.1016/j.cretres.2022.105315

Note: The above post is reprinted from materials provided by University of Bath.

Large dinosaur predators, such as Tyrannosaurus rex, evolved different shapes of eye sockets to better deal with high bite forces, new research has shown.

While in many animals — and most dinosaurs — the eye socket is just a circular hole in the skull housing the eyeball, this is very different in large carnivores.

In a new study, published today in Communications Biology, researchers at the University of Birmingham reveal how the unusual elliptical, or oval eye sockets found in the skulls of these predators, could have evolved to help the skull absorb impact as they pounced on prey.

Dr Stephan Lautenschlager, Senior Lecturer for Palaeobiology at the University of Birmingham and author of the new study, analysed the shape of the eye sockets of ca. 500 different dinosaurs and related species.

“The results show that only some dinosaurs had eye sockets that were elliptical or keyhole-shaped,” said Dr Stephan Lautenschlager. “However, all of those were large, carnivorous dinosaurs with skull lengths of 1 m or more.”

Using computer simulations and stress analysis, Dr Lautenschlager tested what purpose these unusual eye socket shapes could have.

The results demonstrated that a skull with a circular eye socket was more prone to high stresses during biting. However, if these were replaced with other eye socket shapes stresses were considerably reduced allowing top predators, including Tyrannosaurus rex, to evolve high bite forces without compromising skull stability.

The study also showed that most plant-eating species and juvenile individuals retained a circular eye socket. Only large carnivores adopted other morphologies, such as elliptical, keyhole-shaped or figure-of-eight-shaped eye sockets.

Dr Lautenschlager added: “In these species, just the upper part of the eye socket was actually occupied by the eyeball. This also led to a relative reduction of eye size compared with skull size.”

The researchers also investigated what would have happened if eye size had increased at the same rate as skull length. In such a case, the eyes of Tyrannosaurus rex would have been up to 30 cm in diameter and weighing nearly 20 kg (instead of estimated 13 cm and 2 kg).

Reference:
Stephan Lautenschlager. Functional and ecomorphological evolution of orbit shape in mesozoic archosaurs is driven by body size and diet. Communications Biology, 2022; 5 (1) DOI: 10.1038/s42003-022-03706-0

Note: The above post is reprinted from materials provided by University of Birmingham.

This has been confirmed in the article ‘New contributions to the skull anatomy of spinosaurid theropods: Baryonychinae maxilla from the Early Cretaceous of Igea (La Rioja, Spain)’ published in the journal Historical Biology by Iker Isasmendi (lead author) and Xavier Pereda of the UPV/EHU-University of the Basque Country, Pablo Navarro of the UR-University of La Rioja, Angélica Torices, director of the Chair of Palaeontology at the UR, plus other experts of the Complutense University of Madrid and the Palaeontological Visitors’ Centre of La Rioja.

Scientists have reassessed fossil jaw remains published by Viera and Torres in 1995 and found in 1983 in a Lower Cretaceous site at Igea (La Rioja, Spain). The remains constitute a fragment of a left maxilla belonging to a carnivorous dinosaur and in which 8 alveoli have been preserved. Using microCT techniques, they discovered the remains of several teeth developing simultaneously in one of these dental sockets.

“We recognised up to three generations of teeth in the same alveolus: the functional tooth of the animal, another tooth being formed and which would replace the first, and the germ of the one that would end up replacing the second,” explained Pablo Navarro of the UR.

“This suggests very rapid tooth replacement and is probably one of the reasons why so many spinosaurid teeth can be found on the Iberian Peninsula during the Lower Cretaceous,” added the co-author of the paper.

To date, some species of spinosaurids -medium/large carnivorous dinosaurs with elongated skulls and crocodile-like conical teeth- were known to replace their teeth faster than other theropods, in just two months (replacement rate estimated to be 60-68 days); the research confirms that this is a trait shared by the whole group and provides evidence of how this change occurred, i.e. it was made possible by the development of several replacement teeth at the same time.

“Throughout their lives these animals grew new teeth that gradually replaced the original ones and caused them to fall out. This means that the same animal could generate multiple teeth,” said Pablo Navarro.

“These teeth, more or less conical in shape and a centimetre in size, were transported by rivers, accumulated in lake areas and, over time, became fossilised,” said the researcher. They are one of the most common vertebrate remains in Iberian sites of the Lower Cretaceous (between 145 and 113 million years ago).”

Although it is not known precisely why their teeth were replaced so often, it is believed that this allowed them to possess a greater number of functional teeth at all times. This was a decisive advantage when withstanding the considerable effort required to hold their prey by trapping them between their jaws.

In addition to these findings, the research has enabled the classification of the jaw studied to be clarified: the experts do not attribute it, as previously thought, to the genus Baryonix, but to another type of spinosaurid very close to it, an indeterminate baryonychid.

The palaeontological studies carried out to date at Igea are significant because of the presence of numerous spinosaur skeletal remains, including partial skeletons belonging to several individuals. “The current research will allow our knowledge about the diversity of this unique group of carnivorous dinosaurs to be improved. It is likely that at least two different species are represented at the Igea sites,” said Erik Isasmendi and Xabier Pereda-Suberbiola, palaeontologists in the UPV/EHU’s Department of Geology; consequently, this Riojan locality is one of the world’s leading locations in the study of spinosaurs.

Reference:
Erik Isasmendi, Pablo Navarro-Lorbés, Patxi Sáez-Benito, Luis I. Viera, Angelica Torices, Xabier Pereda-Suberbiola. New contributions to the skull anatomy of spinosaurid theropods: Baryonychinae maxilla from the Early Cretaceous of Igea (La Rioja, Spain). Historical Biology, 2022; 1 DOI: 10.1080/08912963.2022.2069019

Note: The above post is reprinted from materials provided by University of the Basque Country.

Fossils of small plesiosaurs, long-necked marine reptiles from the age of dinosaurs, have been found in a 100-million year old river system that is now Morocco’s Sahara Desert. This discovery suggests some species of plesiosaur, traditionally thought to be sea creatures, may have lived in freshwater.

Plesiosaurs, first found in 1823 by fossil hunter Mary Anning, were prehistoric reptiles with small heads, long necks, and four long flippers. They inspired reconstructions of the Loch Ness Monster, but unlike the monster of Lake Loch Ness, plesiosaurs were marine animals — or were widely thought to be.

Now, scientists from the University of Bath and University of Portsmouth in the UK, and Université Hassan II in Morocco, have reported small plesiosaurs from a Cretaceous-aged river in Africa.

The fossils include bones and teeth from three-metre long adults and an arm bone from a 1.5 metre long baby. They hint that these creatures routinely lived and fed in freshwater, alongside frogs, crocodiles, turtles, fish, and the huge aquatic dinosaur Spinosaurus.

These fossils suggest the plesiosaurs were adapted to tolerate freshwater, possibly even spending their lives there, like today’s river dolphins.

The new paper was headed by University of Bath Student Georgina Bunker, along with Nick Longrich from the University of Bath’s Milner Centre for Evolution, David Martill and Roy Smith from the University of Portsmouth, and Samir Zouhri from the Universite Hassan II.

The fossils include vertebrae from the neck, back, and tail, shed teeth, and an arm bone from a young juvenile.

“It’s scrappy stuff, but isolated bones actually tell us a lot about ancient ecosystems and animals in them. They’re so much more common than skeletons, they give you more information to work with” said Dr. Nick Longrich, corresponding author on the paper.

“The bones and teeth were found scattered and in different localities, not as a skeleton. So each bone and each tooth is a different animal. We have over a dozen animals in this collection.”

Whilst bones provide information on where animals died, the teeth are interesting because they were lost while the animal was alive — so they show where the animals lived.

What’s more, the teeth show heavy wear, like those fish-eating dinosaur Spinosaurus found in the same beds.

The scientists say that implies the plesiosaurs were eating the same food- chipping their teeth on the armored fish that lived in the river. This hints they spent a lot of time in the river, rather than being occasional visitors.

While marine animals like whales and dolphins wander up rivers, either to feed or because they’re lost, the number of plesiosaur fossils in the river suggest that’s unlikely.

A more likely possibility is that the plesiosaurs were able to tolerate fresh and salt water, like some whales, such as the beluga whale.

It’s even possible that the plesiosaurs were permanent residents of the river, like modern river dolphins. The plesiosaurs’ small size would have let them hunt in shallow rivers, and the fossils show an incredibly rich fish fauna.

Dr Longrich said: “We don’t really know why the plesiosaurs are in freshwater.

“It’s a bit controversial, but who’s to say that because we paleontologists have always called them ‘marine reptiles’, they had to live in the sea? Lots of marine lineages invaded freshwater.”

Freshwater dolphins evolved at least four times — in the Ganges River, the Yangtze River, and twice in the Amazon. A species of freshwater seal inhabits Lake Baikal, in Siberia, so it’s possible plesiosaurs adapted to freshwater as well.

The plesiosaurs belong to the family Leptocleididae- a family of small plesiosaurs often found in brackish or freshwater elsewhere in England, Africa, and Australia. And other plesiosaurs, including the long-necked elasmosaurs, turn up in brackish or fresh waters in North America and China.

Plesiosaurs were a diverse and adaptable group, and were around for more than 100 million years. Based on what they’ve found in Africa — and what other scientists have found elsewhere — the authors suggest they might have repeatedly invaded freshwater to different degrees.

“We don’t really know, honestly. That’s how paleontology works. People ask, how can paleontologists know anything for certain about the lives of animals that went extinct millions of years ago? The reality is, we can’t always. All we can do is make educated guesses based on the information we have. We’ll find more fossils. Maybe they’ll confirm those guesses. Maybe not.”

“It’s been really interesting to see the direction this project has gone in,” said lead author Georgina Bunker. The study initially began as an undergraduate project involving a single bone, but over time, more plesiosaur fossils started turning up, slowly providing a clearer picture of the animal.

The new discovery also expands the diversity of Morocco’s Cretaceous. Said Dr. Samir Zouhri, “This is another sensational discovery that adds to the many discoveries we have made in the Kem Kem over the past fifteen years of work in this region of Morocco. Kem Kem was truly an incredible biodiversity hotspot in the Cretaceous.”

“What amazes me” said coauthor Dave Martill, “is that the ancient Moroccan river contained so many carnivores all living alongside each other. This was no place to go for a swim.”

But what does this all mean for the plausibility of something like a Loch Ness Monster? On one level, it’s plausible. Plesiosaurs weren’t confined to the seas, they did inhabit freshwater. But the fossil record also suggests that after almost a hundred and fifty million years, the last plesiosaurs finally died out at the same time as the dinosaurs, 66 million years ago.

Reference:
Georgina Bunker, David M. Martill, Roy Smith, Samir Zourhi, Nick Longrich. Plesiosaurs from the fluvial Kem Kem Group (mid-Cretaceous) of eastern Morocco and a review of non-marine plesiosaurs. Cretaceous Research, 2022; 105310 DOI: 10.1016/j.cretres.2022.105310

Note: The above post is reprinted from materials provided by University of Bath.

A new study refutes a provocative claim made earlier this year that fossils classified as the dinosaur Tyrannosaurus rex represent three separate species. The rebuttal, published today in the journal Evolutionary Biology and led by paleontologists at the American Museum of Natural History and Carthage College, finds that the earlier proposal lacks sufficient evidence to split up the iconic species.

“Tyrannosaurus rex remains the one true king of the dinosaurs,” said study co-author Steve Brusatte, a paleontologist at the University of Edinburgh who conducted his Ph.D. work at the Museum. “Recently, a bold theory was announced to much fanfare: what we call T. rex was actually multiple species. It is true that the fossils we have are somewhat variable in size and shape, but as we show in our new study, that variation is minor and cannot be used to neatly separate the fossils into easily defined clusters. Based on all the fossil evidence we currently have, T. rex stands alone as the single giant apex predator from the end of the Age of Dinosaurs in North America.”

In March 2022, authors of the controversial study, also published in Evolutionary Biology, made the case that T. rex should be reclassified as three species: the standard T. rex, the bulkier “T. imperator,” and the slimmer “T. regina.” The study was based on analysis of the leg bones and teeth of 38 T. rex specimens.

The authors of the new study revisited the data presented in the earlier paper and also added data points from 112 species of living dinosaurs — birds — and from four non-avian theropod dinosaurs. They found that the multiple species argument was based on a limited comparative sample, non-comparable measurements, and improper statistical techniques.

“Their study claimed that the variation in T. rex specimens was so high that they were probably from multiple closely related species of giant meat-eating dinosaur,” said James Napoli, co-lead author of the rebuttal study and a graduating doctoral student in the Museum’s Richard Gilder Graduate School. “But this claim was based on a very small comparative sample. When compared to data from hundreds of living birds, we actually found that T. rex is less variable than most living theropod dinosaurs. This line of evidence for proposed multiple species doesn’t hold up.”

“Pinning down variation in long-extinct animals is a major challenge for paleontologists,” said co-lead author Thomas Carr from Carthage College. “Our study shows that rigorous statistical analyses that are grounded in our knowledge of living animals is the best way to clarify the boundaries of extinct species. In practical terms, the three-species model is so poorly defined that many excellent specimens can’t be identified. That’s a clear warning sign of a hypothesis that doesn’t map onto the real world.”

The original paper asserted that variation in the size of the second tooth in the lower jaw, in addition to robustness of the femur, indicated the presence of multiple species. But the authors of the new study could not replicate the tooth findings, and they recovered different results from their own measurements of the same specimens. In addition, the authors of the new study took issue with how the “breakpoints” for each species using these traits were statistically determined. The statistical analysis in the original study defined the number of groups before the test was run, so it is not useful for testing the hypothesis, according to the authors of the new study. In the latest study, a different statistical technique was used to determine how many clusters exist within the data without any advanced assumptions, finding that they are best considered as a single group — in other words, one species — T. rex.

“The boundaries of even living species are very hard to define: for instance, zoologists disagree over the number of living species of giraffe,” said co-author Thomas Holtz, from the University of Maryland and the National Museum of Natural History. “It becomes much more difficult when the species involved are ancient and only known from a fairly small number of specimens. Other sources of variation — changes with growth, with region, with sex, and with good old-fashioned individual differences — have to be rejected before one accepts the hypothesis that two sets of specimens are in fact separate species. In our view, that hypothesis is not yet the best explanation.”

“T. rex is an iconic species and an incredibly important one for both paleontological research and communicating to the public about science, so it’s important that we get this right,” said co-author David Hone, from Queen Mary University of London. “There is still a good chance that there is more than one species of Tyrannosaurus out there, but we need strong evidence to make that kind of decision.”

Reference:
Thomas D. Carr, James G. Napoli, Stephen L. Brusatte, Thomas R. Holtz, David W. E. Hone, Thomas E. Williamson, Lindsay E. Zanno. Insufficient Evidence for Multiple Species of Tyrannosaurus in the Latest Cretaceous of North America: A Comment on “The Tyrant Lizard King, Queen and Emperor: Multiple Lines of Morphological and Stratigraphic Evidence Support Subtle Evolution and P. Evolutionary Biology, 2022; DOI: 10.1007/s11692-022-09573-1

Note: The above post is reprinted from materials provided by American Museum of Natural History.

A team co-led by University of Minnesota Twin Cities researcher Peter Makovicky and Argentinean colleagues Juan Canale and Sebastian Apesteguía has discovered a new huge, meat-eating dinosaur, dubbed Meraxes gigas. The new dinosaur provides clues about the evolution and biology of dinosaurs such as the Carcharodontosaurus and Tyrannosaurus rex — specifically, why these animals had such big skulls and tiny arms.

The study is published in Current Biology, a peer-reviewed scientific biology journal.

The researchers initially discovered Meraxes in Patagonia in 2012 and have spent the last several years extracting, preparing, and analyzing the specimen. The dinosaur is part of the Carcharodontosauridae family, a group of giant carnivorous theropods that also includes Giganotosaurus, one of the largest known meat-eating dinosaurs and one of the reptilian stars of the recently released “Jurassic World: Dominion” movie.

Though not the largest among carcharodontosaurids, Meraxes was still an imposing animal measuring around 36 feet from snout to tail tip and weighing approximately 9,000 pounds. The researchers recovered the Meraxes from rocks that are around 90-95 million years old, alongside other dinosaurs including several long-necked sauropod specimens.

Meraxes is among the most complete carcharodontosaurid skeleton paleontologists have found yet in the southern hemisphere and includes nearly the entirety of the animal’s skull, hips, and both left and right arms and legs.

“The neat thing is that we found the body plan is surprisingly similar to tyrannosaurs like T. rex,” said Peter Makovicky, one of the principal authors of the study and a professor in the University of Minnesota N.H. Winchell School of Earth and Environmental Sciences. “But, they’re not particularly closely related to T. rex. They’re from very different branches of the meat-eating dinosaur family tree. So, having this new discovery allowed us to probe the question of, ‘Why do these meat-eating dinosaurs get so big and have these dinky little arms?'”

“The discovery of this new carcharodontosaurid, the most complete up to now, gives us an outstanding opportunity to learn about their systematics, paleobiology, and true size like never before,” said Sebastian Apesteguía, a co-author of the study and a researcher at Maimónides University in Argentina.

With the statistical data that Meraxes provided, the researchers found that large, mega-predatory dinosaurs in all three families of therapods grew in similar ways. As they evolved, their skulls grew larger and their arms progressively shortened.

The possible uses of the tiny forelimbs in T. rex and other large carnivorous dinosaurs have been the topic of much speculation and debate.

“What we’re suggesting is that there’s a different take on this,” Makovicky said. “We shouldn’t worry so much about what the arms are being used for, because the arms are actually being reduced as a consequence of the skulls becoming massive. Whatever the arms may or may not have been used for, they’re taking on a secondary function since the skull is being optimized to handle larger prey.”

The researchers also found that carcharodontosaurids including species from Patagonia evolved very quickly, but then disappeared suddenly from the fossil record very soon after.

“Usually when animals are on the verge of extinction, it’s because they’re evolutionary rates are quite slow, meaning they aren’t adapting very quickly to their environment,” explained Juan Canale, the study’s lead author and a researcher at the National University of Río Negro. “Here, we have evidence that Meraxes and its relatives were evolving quite fast and yet within a few million years of being around, they disappeared, and we don’t know why. It’s one of these finds where you answer some questions, but it generates more questions for the future.”

The research was funded by the National Geographic Society, Municipalidad de Villa El Chocón, Fundación “Félix de Azara,” and the Field Museum in Chicago.

In addition to Makovicky, Apesteguía, and Canale, the research team included National University of Río Negro researcher Alejandro Haluza; Maimónides University researcher Pablo Gallina; West Virginia Institute of Technology Assistant Professor Jonathan Mitchell; Natural History Museum of Los Angeles County researcher Nathan Smith; Carleton University researchers Thomas Cullen; Akiko Shinya of the Field Museum in Chicago; and National University of San Luis researcher Federico Gianechini.

Reference:
Juan I. Canale, Sebastián Apesteguía, Pablo A. Gallina, Jonathan Mitchell, Nathan D. Smith, Thomas M. Cullen, Akiko Shinya, Alejandro Haluza, Federico A. Gianechini, Peter J. Makovicky. New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction. Current Biology, 2022; DOI: 10.1016/j.cub.2022.05.057

Note: The above post is reprinted from materials provided by University of Minnesota.

Research led by palaeontologists at the University of Southampton has identified the remains of one of Europe’s largest ever land-based hunters: a dinosaur that measured over 10m long and lived around 125 million years ago.

Several prehistoric bones, uncovered on the Isle of Wight, on the south coast of England, and housed at Dinosaur Isle Museum in Sandown, belonged to a type of two-legged, crocodile-faced predatory dinosaur known as spinosaurids. Dubbed the ‘White Rock spinosaurid’ — after the geological layer in which it was found — it was a predator of impressive proportions.

“This was a huge animal, exceeding 10 m in length and probably several tonnes in weight. Judging from some of the dimensions, it appears to represent one of the largest predatory dinosaur ever found in Europe — maybe even the biggest yet known,” said PhD student Chris Barker, who led the study. “It’s a shame it’s only known from a small amount of material, but these are enough to show it was an immense creature.”

The discovery follows previous work on spinosaurids by the University of Southampton team, which published a study on the discovery of two new species in 2021.

The bones of the ‘White Rock spinosaurid’, which include huge pelvic and tail vertebrae, amongst other pieces, were discovered near Compton Chine, on the southwest coast of the Isle of Wight. The Cretaceous rocks are famous for their dinosaurs, but little appreciated is the fact that the Island’s fossil record preserves dinosaurs from more than one section of history — and some of those sections, even today, are poorly known.

“Unusually, this specimen eroded out of the Vectis Formation, which is notoriously poor in dinosaur fossils,” said corresponding author Dr Neil Gostling, who teaches evolution and palaeobiology at the University of Southampton. “It’s likely to be the youngest spinosaur material yet known from the UK.”

The 125 million year old Vectis Formation preserves the beginning of a period of rising sea levels, where the ‘White Rock spinosaurid’ stalked lagoonal waters and sandflats in search of food.

“Because it’s only known from fragments at the moment, we haven’t given it a formal scientific name” said co-author Darren Naish. He added: “We hope that additional remains will turn up in time.

“This new animal bolsters our previous argument — published last year — that spinosaurid dinosaurs originated and diversified in western Europe before becoming more widespread.”

Marks on the bone also showed how, even after death, the body of this giant probably supported a range of scavengers and decomposers.

“Most of these amazing fossils were found by Nick Chase, one of Britain’s most skilled dinosaur hunters, who sadly died just before the Covid epidemic,” said co-author Jeremy Lockwood, a PhD student at the University of Portsmouth and Natural History Museum. “I was searching for remains of this dinosaur with Nick and found a lump of pelvis with tunnels bored into it, each about the size of my index finger. We think they were caused by bone eating larvae of a type of scavenging beetle. It’s an interesting thought that this giant killer wound up becoming a meal for a host of insects.”

The researchers hope to generate thin sections of the material to look at the microscopic internal properties of the bones in the near future, which may provide information about its growth rate and possible age.

Reference:
Chris T. Barker, Jeremy A.F. Lockwood, Darren Naish, Sophie Brown, Amy Hart, Ethan Tulloch, Neil J. Gostling. A European giant: a large spinosaurid (Dinosauria: Theropoda) from the Vectis Formation (Wealden Group, Early Cretaceous), UK. PeerJ, 2022; 10: e13543 DOI: 10.7717/peerj.13543

Note: The above post is reprinted from materials provided by University of Southampton.