Phytosaurs were a geographically widespread group of semiaquatic reptiles that thrived in the Late Triassic. Everything Dinosaur team members look at the remarkable phytosaur Colossosuchus techniensis and other related genera.

The phylogenetic position of the phytosaurs remains disputed. This is in part as little is known about their ancestral forms. For example, some scientists classify phytosaurs as members of the Archosauria, uniting them in the same clade as crocodiles, pterosaurs, dinosaurs and birds. However, other researchers, notably the American palaeontologist Sterling Nesbitt does not define the Phytosauria as archosaurs, but as close relatives to the Archosauria (Archosauriformes).

Often depicted with a sprawling gait, a trackway assigned to a phytosaur (Apatopus) indicates that these reptiles adopted a “high walk” gait.  They had an erect stance, albeit with a tail drag, and a parasagittal gait, much as crocodiles do today.

Phytosaurs Resembled Extant Crocodilians

These animals superficially resembled crocodilians, although they were not closely related to modern crocodiles. This is an example of convergent evolution.  Convergent evolution is the process through which distantly related or unrelated organisms evolve similar characteristics or adaptations in response to similar environmental pressures.  For instance, most phytosaurs were probably aquatic ambush predators.  They occupied an environmental niche in ancient ecosystems similar to the niche occupied by extant crocodilians.

A museum exhibit featuring a typical phytosaur. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Characteristics of Phytosaurs

Although superficially resembling crocodiles there were notable differences.  For example, the nostrils of phytosaurs were located high up on the skull, almost between the eyes. The nostrils were located atop a dome-like structure towards the posterior of the snout. In crocodilians, the nostrils are located at the tip of their long snouts.

The location of the nostrils in a phytosaur. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

In addition, phytosaurs lacked the bony secondary palate found in crocodilians.  Although, they probably possessed a fleshy secondary palate that enabled them to breathe whilst they had water in their mouths.  Unfortunately, the presumed presence of a fleshy palate is not confirmed in the fossil record, probably due to this structure’s poor preservation potential.

The arrangement of dermal armour was probably different too. Phytosaurs probably had a paired row of armoured scutes running down their backs. In contrast, crocodilians have multiple rows of scutes.

The manus (hand) of these reptiles such as the phytosaur Colossosuchus techniensis consisted of five digits.

A description of the phytosaur manus:

• The manus is short and rounded with digit III being longest.
• Digits II and IV are approximately the same length.
• Moreover, digit V is the smallest digit. Digit I (pollex) is short but robust.
• Claws are present on digits I to IV.
• The largest claws being located on digit I and II.

A description of the phytosaur pes:

• The pes had five digits.
• Digit I was short and quite robust.
• Digits II, III and IV were long and slender.
• Digit IV was the longest.
• It is believed that all the digits had claws.
• Digit V was much reduced and the shortest digit. It did have a small claw.

How Big were the Largest Phytosaurs?

Scientists remain uncertain over the size of the largest taxa.  Some phytosaurs may have been bigger than the largest living crocodilian the Saltwater crocodile (Crocodylus porosus) which rarely exceeds six metres in length. For example, Rutiodon carolinensis from the southeastern United States is thought to have measured about eight metres long.  It is known from numerous fossil specimens including skull material. The largest skull measures seventy-seven cm in length.

Furthermore, Smilosuchus gregorii is thought to have reached a length of around eight metres.  Some body length estimates for this species exceed twelve metres. However, these estimates are based on highly fragmentary specimens. The recently described Indian phytosaur Colossosuchus techniensis is also estimated to have reached a length of around eight metres.

The 2023 scientific paper describing the phytosaur Colossosuchus techniensis:

“A giant phytosaur (Diapsida, Archosauria) from the Upper Triassic of India with new insights on phytosaur migration, endemism and extinction” by Debajit Datta and Sanghamitra Ray published in Papers in Palaeontology.

Mike from Everything Dinosaur commented:

“Intriguingly, there are numerous examples of at least two phytosaur species being coeval.  One species is often narrow-snouted [Dolichorostral] with teeth that are very similar.  The second species often has a much more robust snout [Brachyrostral] with differently shaped teeth.  Often the robust snouted forms have long fangs at the end of their jaws.  This suggests that these two phytosaurs evolved to take advantage of different food resources although they shared the same environment. Niche partitioning seems to have taken place quite frequently within the Phytosauria.”

Visit the Everything Dinosaur website: Prehistoric Animal Figures.

Palaeontologists explain this niche partitioning phenomena by suggesting that the ancestral phytosaur species specialised in eating different things.  They eventually diverged into two closely related but different species. It is remarkable that this evolutionary pattern is repeated so often within the Phytosauria fossil record.

Time to catch up on this year’s dinosaur discoveries.  For instance, a new species of North African carcharodontosaurid was described recently.  The fragmentary fossil material representing Tameryraptor markgrafi was excavated during the expedition to Egypt led by the famous German palaeontologist Ernst Stromer von Reichenbach.  The naming of this new dinosaur (Kellermann, Cuesta and Rauhut), demonstrates that the theropods of the Bahariya Oasis and the Moroccan Kem Kem Group are not as closely related as previously thought.  Researchers have stated that the proposed faunal similarities between these two strata need further examination.

Tameryraptor markgrafi

The partial skeleton from the Egyptian Bahariya Oasis, found in April 1914, consisted of elements from the skull, a partial dorsal vertebra, upper limb ones, the proximal end of the pubis and part of a caudal vertebra.  It was described by Stromer in 1931.  The material was first assigned to the species Megalosaurus saharicus, which had been described from isolated teeth found in geologically older rocks in Algeria. Unfortunately, almost all of the material from the Bahariya Oasis, including these fossils was destroyed during a bombing raid in World War II.

A detailed reassessment of the available information on the Egyptian carcharodontosaurid, including a previously undescribed photograph of the exhibited specimen, revealed that it differed from the Moroccan Carcharodontosaurus saharicus in several ways.  It also possessed a horn-like rugosity on the nasal bone.  These unique characteristics permitted the research team to confidently reassign these fossils, removing them from the C. saharicus taxon and allowing the naming of a new species of North African theropod.

A photograph of the holotype fossil material (SNSB-BSPG 1922 X46) on display. This photograph was taken prior to April 1944. Picture credit: Kellermann et al.

Picture credit: Kellermann et al

The fossils were discovered around two kilometres from Ain Gedid on the Western foot of the Gebel Harra in basal layers of hardened, gypsum-free marl.  The fossil material it thought to be around ninety-five million years old (Cenomanian faunal stage of the Late Cretaceous).

Based on the photographic evidence and a single endocast of the skull that remains, palaeontologists have estimated that Tameryraptor was around ten metres long.

An illustration of the large carcharodontosaurid from the Bahariya Formation (Egypt). It has been named Tameryraptor markgrafi. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Etymology of Tameryraptor

The genus name is derived from one of the more informal names for Egypt (ta-mery), which means beloved land and the Latin word for thief (raptor).  The species name honours Austrian fossil collector Richard Markgraf, who discovered most of the dinosaur remains described by Ernst Stromer von Reichenbach.

The scientific paper: “Re-evaluation of the Bahariya Formation carcharodontosaurid (Dinosauria: Theropoda) and its implications for allosauroid phylogeny” by Maximillian Kellerman, Elena Cuesta and Oliver W. M. Rauhut published in PLOS One.

The award-winning Everything Dinosaur website: Dinosaur and Prehistoric Animal Models.

An American biotech firm has claimed that their gene editing techniques has led to dire wolf de-extinction.  The front cover of the prestigious “Time” magazine features a remarkable photograph of an oversized wolf staring back at the camera.  It is a powerful image, a testament to advances in gene manipulation and editing undertaken by Colossal Biosciences. However, the young wolves named Romulus, Remus along with a younger female named Khaleesi are not Aenocyon dirus.

A photograph of the two males (Romulus and Remus) aged three months. These canids born 10/1/2024 Picture credit: Colossal Biosciences.

Picture credit: Colossal Biosciences (media release received 08/04/2025)

Dire Wolf De-extinction

Early this month, Colossal Biosciences announced the rebirth of the once extinct dire wolf (A. dirus). It was claimed this was the world’s first successfully de-extincted animal.

Commenting on the company’s work CEO Ben Lamm stated:

” I could not be more proud of the team.  This massive milestone is the first of many coming examples demonstrating that our end-to-end de-extinction technology stack works.”

He added:

“Our team took DNA from a 13,000-year-old tooth and a 72,000-year-old skull and made healthy dire wolf puppies. It was once said, any sufficiently advanced technology is indistinguishable from magic. Today, our team gets to unveil some of the magic they are working on and its broader impact on conservation.”

Dr Beth Shapiro (Chief Science Officer) explained that the company’s novel approach to improving an ancient genome in the absence of more complete material set a new standard in gene management.

Team members at Everything Dinosaur first came across Dr Shapiro’s research a decade ago.  Dr Shapiro had written an intriguing book outlining how modern science and gene manipulation could result in the de-extinction of the Woolly Mammoth.

Everything Dinosaur’s review of “How to Clone a Mammoth”: How to Clone a Mammoth (De-extinction).

Dr Shapiro commented:

“Together with improved approaches to recover ancient DNA, these computational advances allowed us to resolve the evolutionary history of dire wolves and establish the genomic foundation for de-extinction – specifically for selecting with confidence dire wolf specific genetic variants that establish our targets for gene editing.”

Challenging the De-extinction of Aenocyon dirus

Whilst the birth of these canids represents a considerable achievement.  Many scientists have cast doubts on the claim that these three animals represent a revival of a long extinct taxon.  The idea that the dire wolf has been resurrected has been challenged.  Extinction remains permanent.  Instead, the scientists at Colossal Biosciences have used synthetic biology technologies to identify in ancient DNA from dire wolf remains key segments of the genetic code that could be manipulated to produce a modified grey wolf (Canis lupus).

In essence, what has been produced is a grey wolf but with some dire wolf-like traits, such as the larger skull and white fur.

The Rebor dire wolf/fantasy figure with its product packaging. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The picture (above) shows a replica of a dire wolf.  It is part of the Rebor range of models and figures.  There has been a renewed interest in dire wolves since they featured in the hit fantasy television series “Game of Thrones”.

To view the range of Rebor figures in stock: Rebor Figures and Models.

Implications for Conservation

The research may have important applications in helping to maintain healthy populations of highly endangered animals. For example, Colossal Biosciences have also produced two litters of red wolves from three different genetic founder lines. The red wolf (Canis rufus) is the most critically endangered wolf in the world.  These litters include one adolescent female red wolf (Hope) and three male red wolf puppies (Blaze, Cinder, and Ash).

Mike from Everything Dinosaur said:

“They are beautiful animals, and they represent an example of the huge advances being made in biosciences.  However, numerous academics and scientists have stated that they are not dire wolves but essentially a modified grey wolf that has some physical traits that represent a different species”.

Colossal Biosciences are continuing to research the de-extinction of other iconic animals.  For example, they are examining the possibility of resurrecting the Thylacine.  In addition, CEO Ben Lamm has claimed that the first Woolly Mammoth calves produced using this type of technology might be born within three years.

Resurrecting the Woolly Mammoth: The Return of the Woolly Mammoth.

The award-winning Everything Dinosaur website: Everything Dinosaur Models.

Scientists have named a unique, two-fingered therizinosaur species.  The fossils of Duonychus tsogtbaatari come from the Upper Cretaceous Bayanshiree Formation of the Gobi Desert (Mongolia).  This is the first time that a reduction of the digits on the manus has been recorded within the Therizinosauridae family.  All other therizinosaurs possessed three fingers on each hand.  Moreover, each finger ended in a curved claw.  Some of the claws of therizinosaurs were huge.  For example, one of the largest, Therizinosaurus cheloniformis had finger claws over a metre in length.

A life reconstruction of Duonychus tsogtbaatari. This dinosaur had two fingers on each hand. Although the fossils from which this new species has been described represent a subadult. Scientists have calculated that It weighed approximately 260 kilograms and was around three metres in length. Picture credit: Tim Bollinger.

Picture credit: Tim Bollinger

Duonychus tsogtbaatari

Duonychus (pronounced due-oh-ny-kus) translates from the Greek as “two claws”.  The species name honours the Mongolian palaeontologist Khishigjav Tsogtbaatar.  The discovery of this therizinosaur is doubly unique.  One of the sheaths on a fossil claw (digit I) has been preserved.  The sheath made from the protein keratin (same as our hair and fingernails), reveals that the claw was much longer than the underlying bone.  It was forty percent longer than the claw’s bony core.  It is the largest claw of its kind found fully preserved in this way.  The total claw length has been estimated at around thirty centimetres.

Duonychus tsogtbaatari was not carnivorous.  These long claws were probably not used to attack other dinosaurs.  Although, they could have had a defensive function or have been used in intraspecific combat.  The researchers studying the fossil material believe the long, curved claws and the ability of Duonychus to flex them would have helped this animal to grasp vegetation.

Duonychus tsogtbaatari data card. Picture credit: Tim Bollinger.

Picture credit: Tim Bollinger

Digit Reduction in Theropod Dinosaurs

The most famous two-fingered theropod dinosaur is Tyrannosaurus rex.  Duonychus is not closely related to T. rex.  However, both these dinosaurs evolved from ancestors that had three digits on each hand.  So, why did some theropod dinosaurs lose digits?  It is likely that the outer fingers of the hand became less useful and so they were gradually reduced over the time.  An evolutionary pathway led to the outer fingers becoming redundant, then vestigial, before finally disappearing altogether. Alternatively, digits I and II became increasingly dominant and thus enlarged.  This led to the eventual reduction and elimination of digit III.

Intriguingly, the hand claws of Duonychus were highly curved.  The researchers conclude that the extremely curved claws were adaptations to help this animal to “hook” branches and pull them within easy reach.  In essence, the reduction of digits was an evolutionary adaptation towards more efficient feeding.

Potential Niche Partitioning?

The sediments of the Bayanshiree Formation preserve a diverse dinosaur biota.  For example, there were at least three other therizinosaurs that were likely coeval with Duonychus.  All the other Bayanshiree Formation therizinosaurs described to date had three fingers on each hand.  With so many therizinosaurs in the same environment, it is possible that Duonychus evolved reduced digits to permit it to feed on different types of vegetation.  The reduced fingers could represent evidence of niche partitioning within the Therizinosauridae associated with these strata.

The four therizinosaurs described from the Bayanshiree Formation to date:

• Segnosaurus (S. galbinensis) named in 1979. One of the largest therizinosaurs known with a length of around seven metres.
• Erlikosaurus (E. andrewsi) named in 1980.  Measuring around three and half metres in length it had a robust beak suggesting a diet of mainly vegetation.
• Enigmosaurus (E. mongoliensis) named in 1983.  Some scientists consider Enigmosaurus a junior synonym of Erlikosaurus.  Although, the discovery of Duonychus lends support to the idea that several different types of therizinosaur were present.
• Duonychus (D. tsogtbaatari) named in 2025.  The first didactyl therizinosaur, possessing only two manual digits. In addition, the keratinous sheath on digit I provides a rare insight into theropod claw structure.

It is also worth noting that several other potential therizinosaur fossil specimens have been excavated from the Bayanshiree Formation.  These have yet to be formally named and described.

Our thanks to Tim Bollinger for permission to use his Duonychus illustrations in the compilation of this article.

Take a look at Tim Bollinger’s work under the moniker UnexpectedDinoLesson:

Instagram – @unexpecteddinolesson
Facebook – @UnexpectedDinoLesson
X (Twitter) – @Dino_Lesson

The scientific paper: “Didactyl therizinosaur with a preserved keratinous claw from the Late Cretaceous of Mongolia” by Yoshitsugu Kobayashi, Darla K. Zelenitsky, Anthony R. Fiorillo and Tsogtbaatar Chinzorig published in the journey iScience.

A fragment of a left femur found in the Atlas Mountains of Morocco is the earliest evidence of the cerapodan clade of dinosaurs.  An open access study, published in the Royal Society Open Science earlier this month posits that this fragmentary specimen is the world’s oldest cerapodan fossil. As such, it is helping palaeontologists to understand the evolutionary origins of one of the most diverse and successful dinosaur groups.

The World’s Oldest Cerapodan

The Cerapoda consists of bird-hipped dinosaurs (part of the Ornithischia). These mainly herbivorous dinosaurs became a major component of Cretaceous terrestrial ecosystems. They dominated the herbivorous niche in Late Cretaceous ecosystems in the Northern Hemisphere. One of the secrets of their evolutionary success is that they evolved sophisticated chewing mechanisms to help them break down plant material. Early cerapodans were small and bipedal. However, by the Late Cretaceous they had evolved obligate quadrupedality and some of these dinosaurs were the largest non-sauropod dinosaurs on Earth.

The term Cerapoda is a combination of the words ceratopsian and ornithopod.

A cerapodan dinosaur skeleton on display.  This is a cast of the enormous duck-billed dinosaur (Edmontosaurus annectens). Hadrosaurs like Edmontosaurus were a major component of Late Cretaceous ecosystems in North America. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Remarkable El Mers III Formation

The fossil was discovered in 2020 by a field team exploring exposures of the El Mers III Formation at Boulahfa, near Boulemane, central Morocco.  The strata were laid down during the Bathonian of the Middle Jurassic (168 to 165 million years ago). This specimen represents the world’s oldest cerapodan. The El Mers III Formation has also yielded the world’s oldest ankylosaur, the first discovered in Africa (Spicomellus afer), as well as one of the oldest stegosaurs.  For example, in 2019 we wrote a blog post about Adratiklit boulahfa, the first stegosaur to be described from North Africa.

To read our blog post about Spicomellus afer: The Earliest Ankylosaur Known to Science and Africa’s First.

Our 2019 article about A. boulahfa: North Africa’s First Stegosaur.

These North African deposits are providing evidence of some of the earliest members of key clades within the Dinosauria.  The fossil (specimen number USMBA 001) consists of a femoral head offset on a distinct neck with a constriction between the head and the trochanter (a ridge that indicates a large muscle attachment).  These anatomical characteristics identify the fossil as coming from a cerapodan dinosaur.

USMBA 001, proximal left femur of a cerapodan dinosaur in (A) anterior, posterior (B) and (C) proximal (dorsal). Lateral view (D) and (E) medial view. Note the key – ar, ridge on the anterior surface; gt, greater trochanter; hd, head; ls, ligament sulcus; tr, trough separating head from greater trochanter; u, u-shaped sulcus; ur, ridges bordering u-shaped sulcus. Scale bar equals 2 cm. Picture credit: Maidment et al (Royal Society Open Science).

Picture credit: Maidment et al (Royal Society Open Science)

The researchers conclude that further sampling of the El Mers III Formation sediments will be crucial in helping to understand the radiation of ornithischian dinosaurs. The research team hope to find more fossil material representing the world’s oldest cerapodan.

Callovosaurus leedsi and a Scottish Fossil

Previously, the oldest definite cerapodan fossil was a partial left femur from the Oxford Clay Formation found at Fletton, near Peterborough, Cambridgeshire. The type species was described by the English naturalist Richard Lydekker in 1889. Originally named Camptosaurus leedsi this dinosaur was redescribed in 1980 (Galton) and renamed Callovosaurus leedsi. Its taxonomy has yet to be resolved. The fossil specimen number NHMUK R1993, could represent a basal iguanodontian or perhaps a dryosaurid.

A fragmentary fossil of an ornithopod (Callovosaurus leedsi). Previously, this fossil represented the oldest cerapodan described to date.

Picture credit: Dean Lomax

The fossil is thought to be approximately 164 million years old.

Rounded, tridactyl footprints from bipedal dinosaurs which are thought to represent cerapodan dinosaurs have been reported from Middle Jurassic sediments from around the world. However, early cerapodan body fossils are exceptionally rare.  A partial dinosaur skeleton from the Isle of Skye, could be another cerapodan.  This specimen is around 166 million years old.  Unfortunately, whilst likely to represent a dinosaur, these fossils are too poorly preserved and fragmentary to definitely identify this material as a representative of the Cerapoda.

To read Everything Dinosaur’s article about the Isle of Skye fossil specimen: Rare Elgol Dinosaur Fossil Scientifically Described.

Defining the Cerapoda

The Cerapoda is a clade within the Ornithischia (bird-hipped dinosaurs). It consists of two distinct subgroups, the Ornithopoda and the Marginocephalia. The clade is extremely diverse.  The ornithopods include iconic dinosaurs such as Iguanodon, Hypsilophodon and the Hadrosauriformes. In turn, the Marginocephalia comprises the horned dinosaurs (Ceratopsia) and the bone-headed dinosaurs (pachycephalosaurs).

The scientific paper: “The world’s oldest cerapodan ornithischian dinosaur from the Middle Jurassic of Morocco” by Susannah Maidment, Driss Ouarhache, Richard J Butler, Khadija Boumir, Ahmed Oussou, Kawtar Ech-charay, Abdessalam El Khanchoufi and Paul M Barrett published in Royal Society Open Science.

Visit the Everything Dinosaur website: Dinosaur and Prehistoric Animal Models.

Recently published temnospondyl research suggests that adopting a generalist feeding ecology helped these ancient amphibians to survive the end-Permian mass extinction event.  The study published this week in the journal “Royal Society Open Science”, concludes temnospondyl’s success lay in their generalist feeding ecology. The temnospondyls consist of an extinct clade comprising around three hundred known species.  They evolved in the Early Carboniferous and persisted until the Early Cretaceous.  This represents a timespan of around two hundred and thirty million years.  Temnospondyls were traditionally classified as amphibians, although their taxonomic affinity with the Amphibia remains controversial.  It is more technically correct to refer to these vertebrates as anamniote tetrapods.

A dorsal view of the CollectA Deluxe Koolasuchus a late surviving temnospondyl from the Early Cretaceous of Australia. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The photograph (above) shows a dorsal view of Koolasuchus cleelandi model. It is the youngest temnospondyl described to date.  Fragmentary fossils are thought to be around 125-120 million years old (Barremian – Aptian faunal stages of the Cretaceous).  The model is from the CollectA Deluxe range of scale prehistoric animal figures.

To view this range of prehistoric animal models: CollectA Deluxe Prehistoric Life Models.

A Mystery of the end-Permian Mass Extinction Event

One of the mysteries of the end-Permian mass extinction was the subsequent success of temnospondyls. This catastrophic global event occurred approximately 252 million years ago.  It was the largest extinction event in the Phanerozoic, marked by the loss of as many as 90% of all species.  Although many types of temnospondyl died out, following this mass extinction temnospondyls diversified rapidly during the Early Triassic.  Numerous lineages arose.  These lineages continued, although with diminishing diversity throughout the remainder of the Triassic.  A few taxa survived into the Jurassic before the temnospondyls are thought to have finally become extinct during the Early Cretaceous.

Researchers led by scientists from the University of Bristol propose that these animals thrived after the mass extinction event by feeding on freshwater prey that evaded terrestrial predators.

By adopting a generalist feeding ecology, these predators could consume a wide variety of prey despite all the environmental changes going on during the Triassic. A broader examination of Triassic ecosystems also indicates that the freshwater habitats temnospondyls preferred provided them with a relatively stable variety of food resources.  This allowed them to thrive while strictly terrestrial predators made do with meagre, unstable resource availability on land.

A Mastodonsaurus rises out of the depths to ambush a small, archiosauriform (Jaxtasuchus). Picture credit: Mark Witton.

Picture credit: Mark Witton

Mastodonsaurus (see image above), is known from the Middle Triassic of Europe.  It was one of the largest temnospondyls, with an estimated body length of more than five metres.

Lead author of the study Aamir Mehmood (University of Bristol School of Biological Sciences), commented:

“One of the great mysteries has been the survival and flourishing of a major group of amphibians called the temnospondyls.  These were predatory animals that fed on fishes and other prey, but were primarily linked to the water, just like modern amphibians such as frogs and salamanders. We know that climates then were hot, and especially so after the extinction event. How could these water-loving animals have been so successful?”

The Triassic “Tropical Dead Zone”

The Early Triassic was a time of repeated volcanic activity leading to long phases of global warming, aridification, reductions in atmospheric oxygen, acid rain and widespread wildfires, creating conditions so hostile that the tropics became devoid of animal life. This “tropical dead zone” drastically impacted the distributions of both marine and terrestrial organisms.

Co-author Dr Suresh Singh said:

“We collected data on a hundred temnospondyls that lived throughout the Triassic and wanted to look at how their ecologies changed. We measured their body sizes and features of the skulls and teeth that tell us about function.”

Dr Armin Elsler another co-author of the temnospondyl research paper added:

“Much to our surprise, we found that they did not change much through the crisis. The temnospondyls showed the same range of body sizes as in the Permian, some of them small and feeding on insects, and others larger. These larger forms included long-snouted animals that trapped fishes and broad-snouted generalist feeders. What was unusual though was how their diversity of body sizes and functional variety expanded about five million years after the crisis and then dropped back.”

Due to the intense global warming of the first five million years of the Triassic, there is evidence that life on land and in the sea moved away from the tropics to avoid the heat.

Professor Mike Benton (University of Bristol) explained:

“Our work shows that the temnospondyls, unexpectedly, were able to cross the tropical dead zone. Fossils are known from South Africa and Australia in the south, as well as North America, Europe and Russia in the north. The temnospondyls must have been able to criss-cross the tropical zone during cooler episodes.”

An exhibit featuring a reconstruction of the skeleton of the giant Permian temnospondyl Eyrops. New research suggests that temnospondyl’s success during the Early Triassic lay in their generalist feeding ecology. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Decline of the Temnospondyls

Aamir summarised the team’s findings stating:

“Their burst of success in the Early Triassic was not followed up. They coped with the hot conditions probably by having a low requirement for food, by being able to eat most prey animals, and by hiding in sparse water bodies. But when the ancestors of dinosaurs and of mammals began to diversify in the Middle Triassic, the temnospondyls began their long decline.”

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

The scientific paper: “The ecology and geography of temnospondyl recovery after the Permian – Triassic mass extinction” by Aamir Mehmood, Dr Suresh Singh, Dr Armin Elsler and Professor Michael Benton published in Royal Society Open Science.

The award-winning Everything Dinosaur website: Prehistoric Animal Models and Toys.

A jumbled set of bones first spotted on a beach on the southern portion of the Isle of Skye in 1973 have been identified as a probable ornithopod.  The Elgol dinosaur fossil is Scotland’s earliest recorded dinosaur fossil discovery.  A research team led by Dr Elsa Panciroli (NERC Independent Research Fellow at National Museums Scotland), visited the site in 2018 and began the challenging process of extracting the fossil specimen from the surrounding boulders.

A specialist Canadian company was invited to supervise the extraction of the rare fossil.  Once the difficult task of releasing the fossil slab was completed, it was carefully loaded onto an inflatable dingy and piloted safely back to port by a local crew from Elgol’s Bella Jane Boat Trips.  The researchers were so worried about the fossil block sinking that they tied several buoys to it in the hope that if the boat should capsize, the rare fossil could still be located.

Lead author Dr Elsa Panciroli with the Elgol dinosaur fossil. The jumbled bones have proved difficult to identify. Picture credit: Neil Hanna.

Picture credit: Neil Hanna

The Dinosaur Fossil Record of Scotland

The fossil record of dinosaurs in Scotland mostly comprises isolated highly fragmentary bones from the Great Estuarine Group in the Inner Hebrides.  These sediments were deposited in the Middle Jurassic (Bajocian–Bathonian faunal stage).  The Elgol dinosaur fossil is estimated to be around 166 million years old. It is the first and most complete partial dinosaur skeleton currently known from Scotland. The material has been assigned a specimen number (NMS G.2023.19.1).

After manual preparation, the scientists were able to identify part of the spine, ribs and elements from the hips (a partial ilium).  Unfortunately, micro-CT scanning failed to help with fossil identification.  However, the team are confident that the material does represent a dinosaur, an ornithischian and most likely an ornithopod.  If it does prove to be an ornithopod, then it would be one of the world’s oldest ornithopod body fossils described to date.

The Elgol dinosaur fossil has been interpreted to represent an early ornithopod. Picture credit: Maija Karala.

Picture credit: Maija Karala

Lead author of the study, Dr Elsa Panciroli stated:

“This was a really challenging extraction, in fact we’d previously felt was too difficult to collect the fossil, but I thought it was really important to study it. I was able to persuade the team to give it a try. It took a lot of hard work from a lot of people, but we did it: finally we can confirm and publish Scotland’s first recorded and most complete dinosaur, and that makes it all worthwhile”.

Cerapodan or Ornithopod Dinosaur

The ornithischian (bird-hipped) clade of the Dinosauria has been subdivided into several groups.  Although the exact taxonomy remains undetermined, most palaeontologists distinguish two main groups. Firstly, there is the Thyreophora which comprises the armoured dinosaurs. In addition, there is the Cerapoda which can be further divided into the Ornithopoda and the Marginocephalia (ceratopsids and pachycephalosaurs).

The partial ilium and a histological analysis of fossil bone led the team to conclude that NMS G.2023.19.1 was definitely ornithischian and probably an early ornithopod. Ornithopods were much more common in the Early and Late Cretaceous.  Famous ornithopods such as Iguanodon, Hypsilophodon and Mantellisaurus are associated with Lower Cretaceous deposits.

A Mantellisaurus scale drawing.  An illustration of an Early Cretaceous ornithopod.  Picture credit: Everything Dinosaur

Picture credit: Everything Dinosaur

The ornithopod illustration (above) is based on the CollectA Age of Dinosaurs Mantellisaurus model that was introduced in 2018.  This was the same year when the fossil was removed from its difficult to access location.

To view the range of CollectA Age of Dinosaur figures, including many ornithopods: CollectA Age of Dinosaurs Figures.

Late Cretaceous ornithopods were extremely successful.  Hadrosaurs became the dominant herbivores in many ecosystems.  The Hadrosauridae family (duck-billed dinosaurs) had a global distribution. Some of these dinosaurs were enormous.  For example, Shantungosaurus from the Late Cretaceous of China reached lengths in excess of fourteen metres.

The Elgol Dinosaur Fossil

The Elgol fossils suggest an animal about the size of a pony.  Histological analysis concluded that the animal was at least eight years of age when it died. The new description of the Elgol dinosaur is published in the Earth and Environmental Science Transactions of the Royal Society of Edinburgh. If the fossil material does represent an ornithischian, as tentatively suggested from the partial ilium and histological sectioning, it represents the geologically youngest known occurrence in Scotland, and first from the Kilmaluag Formation.  This adds to the diversity of dinosaurs known from the Middle Jurassic of the Isle of Skye.

To read an article about the types of dinosaurs that lived in this part of the world during the Middle Jurassic: Tracks of Middle Jurassic Dinosaurs.

A close-up view of the 166-million-year-old Elgol dinosaur fossil. Dr Elsa Panciroli carefully examines the fossil material. Picture credit: Neil Hanna.

Picture credit: Neil Hanna

Co-author of the study, Dr Stig Walsh (National Museums Scotland) said:

“This is a wonderful addition to the rapidly growing set of Jurassic finds from the Isle of Skye which are enabling us to learn more and more about the rich ecosystem of the time. We’ve known there were dinosaurs there for a while, most obviously from the famous footprints at An Corran, Brother’s Point and Duntulm and from individual bones, but it’s exciting to see a more complete, if still partial, skeleton. We’re delighted to add it to the other amazing finds now in the National Collection”.

Other recent Jurassic discoveries from Skye include the description of adult and juvenile mammals of the same species, Krusatodon, which revealed that these mammals grew more slowly than mammals today, and possibly one of the world’s largest Jurassic pterosaurs, Dearc sgiathanach.

To read Everything Dinosaur’s article about the Krusatodon fossils: Providing an Insight into Krusatodon Ontogeny.

To read about the discovery of D. sgiathanach: Fantastic Pterosaur from the Isle of Skye.

More Dinosaur Fossils?

Fellow author Professor Susie Maidment of the London Natural History Museum and the University of Birmingham, added:

“The Elgol dinosaur was a challenge to collect, and has proven perhaps an even bigger challenge to identify. Some aspects of the bones indicate that the specimen may be an ornithopod, a group of plant-eating dinosaurs that are best known from the Cretaceous. This specimen, however, would already have been a fossil by the time that the better-known ornithopods like Iguanodon and Hypsilophodon were walking the Earth. Recent research on the fossils of Elgol has revealed a diverse ecosystem of extraordinarily preserved Middle Jurassic animals, and I’m sure there are more exciting discoveries to come.”

The other authors on the paper were Professor Roger Benson (American Museum of Natural History), Professor Richard Butler (University of Birmingham), Brett Crawford (Research Casting International – RCI), Matt Fear (RCI), Dr Nick Fraser (National Museums Scotland) and Dr Gregory Funston (Royal Ontario Museum).

With the description of the Elgol dinosaur fossil, the significance of the Isle of Skye is once again emphasised.  Furthermore, it demonstrates the importance of this part of Scotland in terms of learning more about the dinosaur biota from the Middle Jurassic.

Everything Dinosaur acknowledges the assistance of a media release downloaded from National Museums Scotland.

The scientific paper: “The first and most complete dinosaur skeleton from the Middle Jurassic of Scotland” by Elsa Panciroli, Gregory F. Funston, Susannah C. R. Maidment, Richard J. Butler, Roger B. J. Benson, Brett L. Crawford, Matt Fair, Nicholas C. Fraser and Stig Walsh published in the Earth and Environmental Science Transactions of The Royal Society of Edinburgh.

The award-winning Everything Dinosaur website: Prehistoric Animal Models.

A newly published scientific paper highlights the uniqueness and diversity of Australian theropods.  The research, published in the Journal of Vertebrate Paleontology identifies the world’s oldest known megaraptorid.  In addition, the study provides the first evidence of the presence of carcharodontosaurs in Australia.  These fossil discoveries are rewriting the evolutionary history of theropod dinosaurs.  Furthermore, they highlight a unique predator hierarchy in Australia during the Early Cretaceous.

The research was led by Museums Victoria Research Institute and Monash University PhD student Jake Kotevski. The scientists describe five new theropod specimens. Three tibiae, and a fossil consisting of two articulated caudal vertebrae with haemal arches, from the upper Strzelecki Group. In addition, the study includes a single tibia from the slightly younger Eumeralla Formation.

Unenlagiinae left tibia (front). Carcharodontosauria left tibia (middle) and Megaraptoridae right tibia (rear). New research highlights the diversity of Early Cretaceous Australian theropods. Picture credit: Nadir Kinani/Museums Victoria.

Picture credit: Nadir Kinani/Museums Victoria

Describing the Theropod Fossils

The five specimens included in the study are:

• Articulated Megaraptoridae caudal vertebrae (NMV P257414) – from upper Strzelecki Group exposures from the Twin Reefs locality.
• A partial right tibia (Megaraptoridae) specimen number NMV P257415 also from upper Strzelecki Group exposures at the Twin Reefs locality.
• Carcharodontosauria indet. left tibia (NMV P186143). A fragmentary fossil collected from the Lesley’s Lair site by Patricia Vickers-Rich in 1988 (upper Strzelecki Group).
• NMV P221042 a Carcharodontosauria indet. right tibia from the Point Lewis locality of the Eumeralla Formation.
• NMV P257601 a crushed left tibia assigned to Unenlagiinae indet. This fossil was found at Eagles Nest, near Inverloch, (upper Strzelecki Group).

For context, the upper Strzelecki Group deposits are dated from 121.4 to 118 million years ago.  Whilst the geologically younger Eumeralla Formation dates from 113 to 108 million years ago.

Fragmentary fossil material found in Australia has been assigned to the Megaraptoridae family previously.  However, these megaraptorid fossils from the upper Strzelecki Group are several million years older.  As such, they are the oldest assigned Megaraptoridae fossil material known to science.  Previously, Everything Dinosaur has reported on the discovery of Australian megaraptor fossil material that dates from approximately 110 million years ago.

To read more about this research: Australian Theropod Bone Challenges Gondwana Break-up Theory.

Megaraptoridae right tibia. Picture credit: Nadir Kinani/Museums Victoria.

Picture credit: Nadir Kinani/Museums Victoria

A Fresh Perspective on Australian Theropods

These newly described theropod fossils offer insights into Victoria’s dinosaur dominated, Early Cretaceous ecosystem.  The fossils suggest that the apex predators were megaraptorids.  In contrast, the coeval carcharodontosaurs were much smaller and lighter.  For example, the partial tibia and articulated caudal vertebrae indicate the presence of megaraptorids that were around six to seven metres in length.  The fossils assigned to carcharodontosaurs indicate much smaller theropods.  A size estimate for the carcharodontosaurs of two to four metres in length has been proposed.

One of the authors of the study, PhD student Jake Kotevski commented:

“The discovery of carcharodontosaurs in Australia is ground-breaking. It’s fascinating to see how Victoria’s predator hierarchy diverged from South America, where carcharodontosaurs reached Tyrannosaurus rex-like sizes up to 13 metres, towering over megaraptorids. Here, the roles were reversed, highlighting the uniqueness of Australia’s Cretaceous ecosystem.”

Two Megaraptoridae caudal (tail) vertebrae and haemal arches. Picture credit: Nadir Kinani/Museums Victoria.

Picture credit: Nadir Kinani/Museums Victoria

Numerous small ornithopods are known from the Early Cretaceous of Victoria.  However, sauropod remains are absent.  This may have favoured the evolution of smaller, cursorial predators such as megaraptors.  Whereas, in South America large carcharodontosaurs were the apex predators.  They probably hunted the abundant sauropods.  This suggests the composition of the herbivorous dinosaurs in each region led to different theropods dominating the ecosystem.

To read a blog post from 2019 about the discovery of a new ornithopod from Victoria: A New Early Cretaceous Ornithopod from Australia is Described (Galleonosaurus).

Evidence of Faunal Interchange

Co-author Dr Thomas Rich (Museums Victoria) added:

“The findings not only expand Australia’s theropod fossil record but offer compelling evidence of faunal interchange between Australia and South America through Antarctica during the Early Cretaceous. The findings also challenge previous assumptions about body-size hierarchies in Gondwanan predator ecosystems highlighting Victoria’s unique Cretaceous fauna.”

Specimen number NMV P257601 has been referred to the Unenlagiinae.  Their taxonomic position within the Theropoda remains controversial.  For example, some palaeontologists consider unenlagiines to be a subfamily of the Dromaeosauridae.  However, other scientists consider, these small, long-snouted dinosaurs as a separate family (Unenlagiidae). Most unenlagiine fossil remains have been found in South America. Historically, Australia had limited evidence for their presence.  Nevertheless, the crushed tibia (NMV P257601) provides further robust evidence for a faunal interchange between South America and Australia across Antarctica.

Jake Kotevski (left) holding Unenlagiinae left tibia and Tim Ziegler (right) holding Megaraptoridae right tibia. Picture credit: Nadir Kinani/Museums Victoria.

Picture credit: Nadir Kinani/Museums Victoria

The Importance of Museum Collections

Co-author Tim Ziegler (Museums Victoria) highlighted the importance of access to museum collections to foster scientific breakthroughs.

He stated:

“Museum collections are crucial to advancing our understanding of prehistoric life. Specimens preserved in the State Collection for decades – unidentifiable until now – are providing new insights into the evolution of dinosaur ecosystems.”

Three of the fossils, uncovered between 2022 and 2023, were first identified by Museums Victoria volunteer Melissa Lowery. This discovery highlights the essential contributions of community members working alongside seasoned researchers to further our understanding of Australia’s Cretaceous past.

An aerial view of Twin Reefs, Bunurong Coastal Reserve (Victoria), the area where some of the dinosaur fossils were found. Picture credit John Broomfield/Museums Victoria.

Picture credit: John Broomfield/Museums Victoria

Everything Dinosaur acknowledges the assistance of a media release from Museums Victoria in the compilation of this article.

The scientific paper: “Evolutionary and paleobiogeographic implications of new carcharodontosaurian, megaraptorid, and unenlagiine theropod remains from the upper Lower Cretaceous of Victoria, southeast Australia” by Jake Kotevski, Ruairidh J. Duncan, Tim Ziegler, Joseph J. Bevitt, Patricia Vickers-Rich, Thomas H. Rich, Alistair R. Evans and Stephen F. Poropat published in the Journal of Vertebrate Paleontology.

The award-winning Everything Dinosaur website: Prehistoric Animal Models.

A scientific paper was published earlier this week that announced two new Hateg Basin sauropod taxa.  These dinosaurs were named Petrustitan hungaricus and Uriash kadici.  At least four sauropod taxa are known from the Hateg Basin.  However, as the sediments in this region cover several million years, it is likely that these four taxa were not contemporaneous.  It is also likely that additional sauropod genera are represented in the fossil deposits.

To read Everything Dinosaur’s earlier blog post about this new study: New Hateg Basin Sauropods are Described.

We have been asked to provide a little more information on the largest of these four sauropod taxa. As this area consisted of a series of large islands at the end of the Cretaceous, it was thought that the dinosaur fauna in this region consisted mostly of dwarf forms.  However, this idea of the Hateg Basin dinosaur fauna representing examples of “island dwarfism” has been challenged.  For example, the newly described U. kadici is thought to amongst the biggest European Late Cretaceous sauropods know to science.

The Hateg Basin Sauropod Fauna – A Complex Picture

The first sauropod to be named and described from this region of western Romania was Magyarosaurus. The German palaeontologist Friedrich von Huene erected this genus in 1932.  He assigned three species to this genus.

1. Magyarosaurus dacus – now recognised as the only valid species.
2. The nomen dubium Magyarosaurus transsylvanicus – a nomen dubium with assigned fossil material thought to represent more than one species of sauropod.
3. Magyarosaurus hungaricus – renamed in 2025 as Petrustitan hungaricus (Verónica Díez Díaz et al).

It is likely that the substantial number of fossils, often isolated and fragmentary remains found in western Romania represent several more, as yet undescribed sauropod taxa.

The Wild Past Magyarosaurus dinosaur model, a replica of this dwarf titanosaur taxon. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The picture shows a model of the dwarf titanosaur Magyarosaurus sent to Everything Dinosaur by Wild Past.

To view the range of Wild Past models and figures in stock: Wild Past Prehistoric Animal Figures.

Uriash kadici – A Giant Amongst Hateg Basin Sauropods

The second, newly described Hateg Basin sauropod is an outlier in terms of size.  Whilst three of the four Hateg Basin sauropod taxa described to date were relatively small, Uriash kadici was much larger. Size estimates vary but it could have had a body length of around twelve metres.

Mike from Everything Dinosaur explained that three of the four known Hateg Basin sauropod taxa were relatively small.  Although size estimates vary, it is possible to compare these four taxa and to produce a scale drawing.

• Magyarosaurus dacus – 3 metres (<1 tonne).
• Paludititan nalatzensis – 6 metres (2 tonnes).
• Petrustitan hungaricus – 6-7 metres (2 tonnes+).
• Uriash kadici – 12 metres (5-8 tonnes).

Comparing the size of Hateg Island sauropods. Uriash kadici is the biggest taxon described to date. Picture credit: Everything Dinosaur from Brian Cooley/Dan Horatiu Popa/Hateg County UNESCO Global Geopark.

Picture credit: Everything Dinosaur from Brian Cooley/Dan Horatiu Popa/Hateg County UNESCO Global Geopark

Uriash kadici is the largest titanosaurian taxon described to date from the Hateg Basin.  It is larger than most of the other Late Cretaceous European titanosaurs.  Its size is only surpassed by Abditosaurus (A. kuehnei).  Abditosaurus fossils come from southern Pyrenees of Spain.  It was formally described in 2022 (Vila et al).  Abditosaurus is thought to have measured around seventeen metres long.

To read a blog post about this dinosaur: Abditosaurus – The First New Dinosaur of 2022.

What’s in a Name?

The genus name comes from the Romanian word ‘uriaș’ (pronounced ‘uriash’). It refers to gigantic humanoid characters from Romanian folklore. The species name honours Ottokár Kadić (1876–1957), a geologist and palaeontologist of the Royal Geological Survey of Hungary and discoverer of several continental vertebrate-bearing fossil localities in the north-western Hateg Basin, including the type locality of Uriash.

Mike from Everything Dinosaur explained that the recent study focusing on the Hateg Basin sauropods had expanded knowledge about European titanosaurs.  However, much remains to be discovered.  New fossil quarries will be opened, and new material will help to fill in the gaps and provide palaeontologists with a better understanding of Late Cretaceous sauropod evolution.

Visit the award-winning Everything Dinosaur website: Dinosaur Toys and Models.

Two new species of Hateg Basin sauropods have been identified.  Their fossils come from the Upper Cretaceous deposits of the Hateg Basin in western Romania.  The discovery of these new taxa can help palaeontologists to better understand dinosaur populations across the planet prior to the end-Cretaceous extinction event. The study led by Verónica Díez Díaz from the Museum für Naturkunde Berlin (Germany) demonstrates how important Europe’s fossils are when it comes to providing a more complete picture of dinosaur extinction.

Scientists from the University College London and the University of Bucharest collaborated in this research.

Hateg Basin Sauropods

The researchers report two new sauropod taxa from the Hateg Basin.  They have been named Petrustitan hungaricus and Uriash kadici. During the Late Cretaceous, much of the Europe was covered by water. However, an archipelago existed in what is known today as eastern Europe. The largest island (Hateg Island) was approximately 120 miles (200 km) from the nearest landmass. Size estimates vary, but it has been suggested that by the very end of the Cretaceous (Maastrichtian faunal stage), Hateg Island covered an area of around thirty thousand square miles. It was roughly the size of the Japanese island Hokkaido.

The archipelago was home to several different sauropod taxa.  The diversity of sauropods in the Late Cretaceous of Europe is much greater than previously thought.  Fifteen years ago, only five sauropod species were known from the Late Cretaceous of Europe.  Today, at least eleven taxa have been identified.  In contrast, only a single sauropod species is known from the Late Cretaceous of America (Alamosaurus sanjuanensis).

Commenting on the significance of this new study into Hateg Basin sauropods, corresponding author Verónica Díez Díaz (Museum für Naturkunde Berlin) stated:

“The extraordinary diversity in a small geographical area like Hațeg Island surprises us. Sauropods of different sizes lived side by side here: from giants over 10 metres long and weighing eight tonnes to dwarfs of just 2.5 metres and weighing less than a tonne. This provides exciting insights into the environmental conditions and the coexistence of different species.”

The researchers propose the presence of three additional, but only partly contemporaneous taxa in the Hateg Basin. These are Paludititan nalatzensis, Petrustitan (‘Magyarosaurus’) hungaricus and the much larger Uriash kadici. U. kadici is amongst the biggest known sauropods of the Late Cretaceous European Archipelago. Picture credit: Brian Cooley/Dan Horatiu Popa/Hațeg County UNESCO Global Geopark.

Picture credit: Brian Cooley/Dan Horatiu Popa/Hațeg County UNESCO Global Geopark

Giants and Dwarf Sauropods

Traditionally, the fauna of Hateg Island was thought to consist mainly of smaller relatives of dinosaur genera found on larger landmasses.  It had been assumed that the dinosaurs of Hateg Island became smaller due to the limited amount of resources on the island.  This biological phenomenon is known as island dwarfism (insular dwarfism).  This idea was postulated by the famous 20th Century polymath Baron Franz Nopcsa von Felső-Szilvás. He argued that the limited resources such as food, water and space on islands would result in a reduction of the size of animals that lived there. These island dwelling populations would become smaller over many generations when compared to their continental counterparts.

For example, the ornithopod Tethyshadros (T. insularis) was once thought to be a dwarf hadrosauroid.  However, subsequent analysis indicates that it was around twenty-five percent larger than previously thought.

To read more about this 2021 study: Sizing up Tethyshadros.

The biota of the Hateg Basin seems to be much more complicated and diverse.  For instance, whilst a number of Hateg Basin sauropods are relatively small, the newly described Uriash kadici may have been more than eleven metres in length.

Co-author Zoltán Csiki-Sava (University of Bucharest) added:

“Local evolution was more complex than expected and shows that not all species reduced their size.”

European Dinosaurs Linked to Gondwanan Lineages

This study also highlights the links between European dinosaur taxa and their relatives in Asia, Africa and South America.  The team’s findings strengthen the hypothesis that Late Cretaceous European titanosaurs belonged to Gondwanan lineages that invaded the former area during the Barremian–Albian faunal stages of the Early Cretaceous.  Paul Upchurch (University College London) explained that Gondwanan sauropods migrated into Europe over land bridges that existed in the Early Cretaceous.  However, sauropods were probably very capable swimmers and may have traversed distances in excess of three hundred miles (500 kilometres) to reach distant islands.

Co-author Philip Mannion (University College London) commented:

“Some of these dinosaurs were descendants of earlier faunas, while others arrived in the region late.”

Why were Large Hateg Island Sauropods Present?

The researchers interpret the presence of body-size disparity as either evidence that large-bodied taxa were ecologically excluded from body-size reduction by competition with small-bodied titanosaurs, or that dwarfing occurred stratigraphically earlier among several lineages and the small-bodied titanosaurs on Hațeg Island are the descendants of existing dwarfed ancestors. In addition, the team report that they found no indication of a body size-related titanosaurian turnover in the uppermost Cretaceous of the Transylvanian area.

Everything Dinosaur acknowledges the assistance of a media release from the Museum für Naturkunde Berlin in the compilation of this article.

The scientific paper: “Revision of Romanian sauropod dinosaurs reveals high titanosaur diversity and body-size disparity on the latest Cretaceous Haţeg Island, with implications for titanosaurian biogeography” by Verónica Díez Díaz, Philip D. Mannion, Zoltán Csiki-Sava and Paul Upchurch published in the Journal of Systematic Palaeontology.

The award-winning Everything Dinosaur website: Prehistoric Animal Models and Toys.