A remarkable fossil discovery has been made in Wales. Palaeontologists have identified a new, Triassic dinosaur species named Newtonsaurus cambrensis. The fossil was first reported back in 1899, yet it was never properly studied until now.  The fossil material had been referred to in many scientific papers.  A scientific name had been erected – Zanclodon cambrensis by the British palaeontologist Edwin Tully Newton. This name is not valid, the genus name having been used previously to describe an archosauriform from southern Germany.

Using modern, digital scanning techniques researchers have been able to confirm that the fossil material represents a theropod dinosaur. Owain Evans, a student at Bristol University, created a three-dimensional digital reconstruction of the dentary material. The fossil is preserved as natural moulds, with the original bone lost. By digitally scanning and fusing the moulds, the team rebuilt the jaw in striking detail. Every ridge, groove, and serrated tooth was revealed.

The new name honours Edwin Newton.

A plaster cast of the left dentary of Newtonsaurus cambrensis. Picture credit: BGS NERC from “Dinosaurs of the British Isles” by Dean R. Lomax and Nobumichi Tamura.

Picture credit: BGS NERC

Newtonsaurus cambrensis

Writing in the Proceedings of the Geologists’ Association, the researchers suggest that the fossils represent a neotheropod similar to Liliensternus and Dilophosaurus. The jaw was over half a metre long. This suggests a theropod of approximately five to seven metres in length.  Poorly preserved bivalves in the matrix, enabled the scientists to confirm the age of the fossils (Rhaetian faunal stage of the Late Triassic).

Co-author of the study, Professor Michael Benton (University of Bristol), explained that the digital reconstruction gave scientists a much clearer idea of the anatomy.   This paper confirms the presence of large predatory dinosaurs in the area that was to become Wales around 200 million years ago. The research highlights the value of museum collections. Long-stored specimens can still yield significant results.

Part of the holotype (BGS GSM 6532 of Newtonsaurus. The right side of the left dentary, complete with teeth in situ. Picture credit: BCS NERC from “Dinosaurs of the British Isles” by Dean R. Lomax and Nobumichi Tamura.

Shares Characteristics with a European Coelophysoid

The detailed analysis of the digital images indicates that the dentary has characteristics with European coelophysoids of similar geological age (Liliensternus and Dracoraptor).  However, it was much larger.  The research team propose that Newtonsaurus was not a megalosauroid, as previously suggested.

Dracoraptor is also from Wales.  To read Everything Dinosaur’s blog post about the discovery of Dracoraptor: Wales Gets a New Dinosaur – Dracoraptor.

It is uncertain whether it might be an averostran or tetanuran. Its close similarity to Dilophosaurus suggests that this left dentary specimen represents a more derived basal neotheropod. Therefore, it is assigned as a new species (Newtonsaurus cambrensis).

Mike from Everything Dinosaur commented:

“This study shows the power of re-examining old fossils. Museum specimens can still reveal new dinosaurs and transform our understanding of the Dinosauria.”

The scientific paper: “Re-assessment of a large archosaur dentary from the Late Triassic of South Wales, United Kingdom” by Owain Evans, Cindy Howells, Nathan Wintle and Michael J. Benton published in the Proceedings of the Geologists’ Association.

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

A remarkable, semi-articulated and near-complete ichthyosaur skeleton from the famous “Jurassic Coast” of Dorset helps to fill an important gap in the fossil record of ichthyosaurs.  Named Xiphodracon goldencapensis, this dolphin-sized marine reptile lived in the Early Jurassic.  Specifically, it lived during the Pliensbachian stage of the Early Jurassic.  The fossil material consisting of a stunning, three-dimensionally preserved skull along with extensive postcranial remains is around 186 to 184 million years old.  These fossils could represent the most complete reptile specimen known from the Pliensbachian.

Dr Dean Lomax and Professor Judy Massare study the skeleton of the newly named sword dragon ichthyosaur, Xiphodracon goldencapensis, at the Royal Ontario Museum, Toronto, Canada. Picture credit: Dr Dean Lomax.

Picture credit: Dr Dean Lomax

From Golden Cap

The fossils were discovered in the cliffs near Golden Cap between Bridport and Charmouth on the Dorset coast.  The material was found by fossil collector Chris Moore.  Chris has found several important marine reptile specimens, including other ichthyosaurs.  For example, in 2018 the BBC featured another ichthyosaur fossil discovery from Dorset in the documentary “Attenborough and the Sea Dragon”.  Ironically, the ichthyosaur featured in the television programme was probably killed by another ichthyosaur.  The newly named Xiphodracon goldencapensis may have suffered a similar grisly end.  The top of the skull bears evidence of a bite from a much larger marine reptile.

It has been postulated that the three-metre-long Xiphodracon may have been attacked by a Temnodontosaurus.  Temnodontosaurus is a genus of large, predatory ichthyosaurs, some of which could have reached lengths in excess of ten metres.

Ironically, the Temnodontosauridae persisted throughout the earlier Sinemurian stage of the Early Jurassic, through the Pliensbachian and into the Toarcian. However, the composition of the taxa represented by this period of time changed dramatically.

Ichthyosaur expert and co-author of the study, Professor Judy Massare, from the State University of NY at Brockport, (USA) stated:

“Thousands of complete or nearly complete ichthyosaur skeletons are known from strata before and after the Pliensbachian. The two faunas are quite distinct, with no species in common, even though the overall ecology is similar. Clearly, a major change in species diversity occurred sometime in the Pliensbachian. Xiphodracon helps to determine when the change occurred, but we still don’t know why.”

The skeleton and skull of the newly named sword dragon ichthyosaur, Xiphodracon goldencapensis. Picture credit: Dr Dean Lomax.

Picture credit: Dr Dean Lomax

Ichthyosaurs from the Pliensbachian are incredibly rare and this makes Xiphodracon a vital piece of evidence for scientists studying this critical but poorly understood time in ichthyosaurian evolution.

Xiphodracon goldencapensis – “Sword Dragon of Dorset”

The skull has an enormous eye socket. In addition, the rostrum is elongated.  Stomach contents may have been preserved, and they indicate that this ichthyosaur dined on fish and possibly squid. The study was undertaken by a trio of international palaeontologists led by ichthyosaur expert Dr Dean Lomax, an Honorary Research Fellow at The University of Manchester and an 1851 Research Fellow at the University of Bristol.

Dr Lomax has also played a crucial role in the development of Everything Dinosaur’s own range of prehistoric animal figures: Everything Dinosaur Evolution.

Dr Lomax commented:

“I remember seeing the skeleton for the first time in 2016. Back then, I knew it was unusual, but I did not expect it to play such a pivotal role in helping to fill a gap in our understanding of a complex faunal turnover during the Pliensbachian. This time is pretty crucial for ichthyosaurs as several families went extinct and new families emerged, yet Xiphodracon is something you might call a ‘missing piece of the ichthyosaur puzzle’. It is more closely related to species in the later Early Jurassic (in the Toarcian), and its discovery helps pinpoint when the faunal turnover occurred, being much earlier than expected.”

Dr Dean Lomax photographing the skeleton of the newly named sword dragon ichthyosaur, Xiphodracon goldencapensis, at the Royal Ontario Museum, Toronto, Canada. Picture credit: Dr Dean Lomax.

Picture credit: Dr Dean Lomax

Acquired by the Royal Ontario Museum (Toronto, Canada)

After its discovery in 2001, the skeleton was acquired by the Royal Ontario Museum, Canada.  It became part of their extensive collection of ichthyosaurs but had remained unstudied.

Co-author, Dr Erin Maxwell, (State Museum of Natural History Stuttgart, Germany) explained:

“This skeleton provides critical information for understanding ichthyosaur evolution, but also contributes to our understanding of what life must have been like in the Jurassic seas of Britain. The limb bones and teeth are malformed in such a way that points to serious injury or disease while the animal was still alive, and the skull appears to have been bitten by a large predator – likely another much larger species of ichthyosaur – giving us a cause of death for this individual. Life in the Mesozoic oceans was a dangerous prospect.”

Dr Dean Lomax with the skull of the newly named sword dragon ichthyosaur, Xiphodracon goldencapensis, at the Royal Ontario Museum, Toronto, Canada. Picture credit: Dr Dean Lomax.

Picture credit: Dr Dean Lomax

Collectively, the research team identified several unique features in Xiphodracon that have never been observed in any other ichthyosaur. The most peculiar (autapomorphy) is a strange and unique bone around the nostril (called a lacrimal) that has prong-like bony structures.

Dr Lomax added:

“One of the coolest things about identifying a new species is that you get to name it! We opted for Xiphodracon because of the long, sword-like snout (xipho from Greek xiphos for sword) and dracon (Greek and Latin for dragon) in reference to ichthyosaurs being referred to as ‘sea dragons’ for over two hundred years.”

There are plans to put this remarkable ichthyosaur specimen on display at the Royal Ontario Museum.

A close-up of the skull of the newly named sword dragon ichthyosaur, Xiphodracon goldencapensis. Picture credit: Dr Dean Lomax.

Picture credit: Dr Dean Lomax

“The Secret Lives of Dinosaurs”

October has been an exceptionally busy month for Dr Lomax.  In addition, to the publication of this new study he has recently published a new book.  Entitled “The Secret Lives of Dinosaurs” it highlights behaviours of long extinct prehistoric animals through a study of some of the most astonishing fossils ever found.

To learn more about this remarkable book, visit the publisher’s website: Columbia University Press and search for Dr Dean Lomax.

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

The scientific paper: “A new long and narrow-snouted ichthyosaur illuminates a complex faunal turnover during an undersampled Early Jurassic (Pliensbachian) interval” by Dean R. Lomax, Judy A. Massare and Erin E. Maxwell published in Papers in Palaeontology.

Visit the award-winning Everything Dinosaur website: Prehistoric Animal Figures.

A fossil discovery made on the Isle of Skye reveals clues to the origins of modern snakes and lizards.  The animal, named Breugnathair elgolensis, lived during the Bathonian stage of the Middle Jurassic.  The fragmentary and disarticulated fossils are approximately 167 million years old.  The scientific paper has been published in the journal “Nature”.

Breugnathair elgolensis life reconstruction. Picture credit: Brennan Stokkermans (National Museums of Scotland).

Picture credit: Brennan Stokkermans (National Museums of Scotland)

Meet Breugnathair elgolensis

This reptile had the proportions and limbs of a lizard.  However, its jaws, lined with highly recurved teeth, were similar to the jaws of extant pythons.  The fossil specimen represents one of the oldest and most complete Jurassic lizards discovered to date. It has been classified as a member of the Squamata order.  The squamates include lizards and snakes. The evolutionary origins of the Squamata remain open to debate.  Although, many palaeontologists consider that the first squamates evolved in the Early Jurassic around 190 million years ago.

The fossil was discovered near Elgol by Dr Stig Walsh (National Museums Scotland). This rare fossil is now part of the Museum’s vertebrate fossil collection.

Dr Stig Walsh with a cast of the Breugnathair elgolensis fossil. Picture credit: Duncan McGlynn.

Picture credit: Duncan McGlynn

The fossil material and others like it will help palaeontologists to better understand the evolution of snakes and lizards.  For example, are snakes are early off-shoot from the lizard lineage or did snake-like characteristics evolve more than once in the Squamata?

The “False Snake of Elgol”

The fossils are exposed on a single limestone slab. The material includes caudal vertebrae, limb bones, ribs as well as bones from the skull.  The scientific name is taken from Gaelic. It translates as “false snake of Elgol”.  It has been placed in a newly created family, the Parviraptoridae. Until now, parviraptorids were known only from fragmentary remains. Some scientists thought they might represent basal snakes. In contrast, other scientists have proposed that parviraptorids were ancestors of all snakes and lizards.

An illustration of Breugnathair elgolensis swallowing a mammaliaform. We suspect that the unfortunate victim is the mammaliaform Krusatodon kirtlingtonensis, fossils of which are also known from the Isle of Skye. Picture credit: Mick Ellison (American Museum of Natural History).

Picture credit: Mick Ellison (American Museum of Natural History)

The illustration (above) depicts a Breugnathair swallowing an early mammaliaform.  The artist could be suggesting that Breugnathair is feeding on a Krusatodon (K. kirtlingtonensis). There have been many remarkable fossil discoveries made on the Isle of Skye.  The exposed strata were laid down in the Middle Jurassic.  Fossiliferous deposits from this time in Earth’s history are rare.

An article about Krusatodon fossils from the Isle of Skye: Providing an Insight into Mammaliaform Ontogeny.

To read an article about a large pterosaur fossil discovered on the Isle of Skye (Dearc sgiathanach): Fantastic Pterosaur Fossil from the Isle of Skye.

A Window into Evolution

Breugnathair elgolensis fossil material reveals a mosaic of primitive and more derived features. This mosaic of advanced traits combined with more primitive characteristics is found in other parviraptorids. The path taken by evolution is unpredictable.

A close view of the cast of the Breugnathair elgolensis fossil. Picture credit: Duncan McGlynn.

Picture credit: Duncan McGlynn

Mike from Everything Dinosaur commented:

“The Isle of Skye is recognised as one of the world’s most important Middle Jurassic fossil locations. Other discoveries include Scotland’s most complete dinosaur, ancient synapsids, and even flying reptiles. Breugnathair demonstrates the diverse palaeoenvironment represented by these deposits.”

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

The scientific paper: “Mosaic anatomy in an early fossil squamate” by Roger B. J. Benson, Stig A. Walsh, Elizabeth F. Griffiths, Zoe T. Kulik, Jennifer Botha, Vincent Fernandez, Jason J. Head and Susan E. Evans published in the journal Nature.

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

This week, the scientific paper announcing the discovery of a new megaraptor from South America was published.  The dinosaur has been named Joaquinraptor casali and it is probably the geologically youngest member of the Megataptoridae described to date.  In the media release there were several field photographs of the Joaquinraptor casali bones.  We were not able to use them all in our blog post about this new theropod. However, we wanted to share them with our readers, so we created a second article.

Joaquinraptor casali bones in the field (2019) shown with a skeletal reconstruction. Known fossil material is highlighted in blue. The photograph shows fossils of the new megaraptor dinosaur species Joaquinraptor casali in the quarry, laying in the positions they had laid for approximately 67 million years. A dentary, teeth, ribs, and several other bones are visible. Picture credit: Marcelo Luna, Laboratorio de Paleontología de Vertebrados Dr Rubén Martínez, Universidad Nacional de la Patagonia San Juan Bosco.

Picture credit: Marcelo Luna, Laboratorio de Paleontología de Vertebrados Dr Rubén Martínez, Universidad Nacional de la Patagonia San Juan Bosco

To read Everything Dinosaur’s earlier blog post about the discovery of Joaquinraptor: A New Species of Megaraptor from Patagonia.

Joaquinraptor casali Bones Photographed

When visitors view dinosaur fossils in a museum they appear, smooth, free from cracks and clean. The Joaquinraptor casali bones photographed at the dig site look different. Skilled technicians spend many hours preparing each fossil for display. They carefully remove rock, repair breaks, and restore missing areas. As a result, the finished fossils look polished and ready for study or exhibition. However, this final appearance is very different from how the bones first look when they are carefully excavated in the field.

Fossils of the new megaraptor species Joaquinraptor casali in the quarry. Picture credit: Marcelo Luna, Laboratorio de Paleontología de Vertebrados Dr Rubén Martínez, Universidad Nacional de la Patagonia San Juan Bosco.

Picture credit: Marcelo Luna, Laboratorio de Paleontología de Vertebrados Dr Rubén Martínez, Universidad Nacional de la Patagonia San Juan Bosco

The picture (above) shows the jumble of fossil bones in the quarry.  The field team take care to extract the fossils. In addition, they map their precise location and gather data on the fossil matrix.

Fragile Bones and Delicate Work in the Field

At the quarry, the Joaquinraptor casali bones are fragile, fragmented, and often extremely difficult to expose. Field team members work slowly with small tools to expose each piece. Dirt, dust, and natural cracks make the fossils appear rough and incomplete. Only after careful cleaning and conservation do these remains reveal their true form. This process highlights the remarkable journey from excavation site to museum gallery.

Mike from Everything Dinosaur commented:

“The media release we received contained some incredible photographs of the quarry.  We wanted to highlight the care and dedication it takes to extract fossils in the field.  Moreover, the fossil material comes from the uppermost part of the Lago Colhué Huapi Formation.  These field photographs are significant as the strata is most likely late Maastrichtian.  This suggests that Joaquinraptor lived close to the Cretaceous/Palaeogene boundary.  Therefore, the Megaraptoridae persisted until the end of the Age of Dinosaurs.”

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

The scientific paper: “Latest Cretaceous megaraptorid theropod dinosaur sheds light on megaraptoran evolution and palaeobiology” by Lucio M. Ibiricu, Matthew C. Lamanna, Bruno N. Alvarez, Ignacio A. Cerda, Julieta L. Caglianone, Noelia V. Cardozo, Marcelo Luna and Rubén D. Martínez published in Nature Communications.

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

A new species of Patagonian megaraptor has been described.  Joaquinraptor casali provides further insight into this enigmatic Cretaceous dinosaur family.  The fossil material casts light on these giant-clawed theropods, as this is only the second member of the Megaraptoridae family to have been discovered with extensive skull remains.  The study has been published in the journal “Nature Communications”.

Intriguingly, the field team found a crocodyliform humerus between the lower jaw bones of Joaquinraptor.  This suggests that that the new megaraptor may have been eating the crocodyliform when it died.  However, this is only an assertion, it is not definitive.  The limb bone could have ended up lodged between the dentaries as a result of being washed into the submerged mouth of the dinosaur’s carcase.

Joaquinraptor casali life reconstruction. The new megaraptor dinosaur species Joaquinraptor casali in what is now central Patagonia, Argentina roughly 67 million years ago. The carnivore holds a crocodyliform (= extinct crocodile relative) front leg in its mouth, in keeping with the discovery of a crocodyliform forelimb bone between the lower jaws. Picture credit: Andrew McAfee, Carnegie Museum of Natural History.

Picture credit: Andrew McAfee, Carnegie Museum of Natural History.

The upper arm bone of the crocodyliform bears tooth marks and the bone was touching some of the megaraptor’s teeth.  So, some kind of interspecific interaction seems likely. Perhaps, the theropod and the crocodyliform were fighting.  For example, the two predators could have been battling over a food resource.

Possible evidence of diet or predation in the new megaraptor dinosaur species Joaquinraptor casali. (a) Dentaries (= tooth-bearing lower jaw bones) of Joaquinraptor and an associated crocodyliform (= extinct crocodile relative) forelimb bone in the position in which they were found, prior to their separation in the laboratory. Detail (b) view showing a portion of the croc forelimb bone in contact with the teeth of Joaquinraptor. The croc bone (c) after its separation from the Joaquinraptor dentaries. Picture credit: Lucio M. Ibiricu et al.

Picture credit: Lucio M. Ibiricu et al

Joaquinraptor casali

Joaquinraptor seems to be quite typical for a megaraptor.  It had a long, low skull lined with serrated teeth and powerful forelimbs. The two innermost talons of the hand were tipped with large claws.  The genus name honours Joaquín, the son of the first author (Lucio M. Ibiricu) and the informal name given to the locality when the skeleton of the taxon was discovered (Valle Joaquín). Dr Gabriel Andrés Casal inspired the species epithet.  Dr Casal has made a significant contribution to our understanding of Cretaceous dinosaurs from Argentina.  In addition, he was responsible for the formal recognition and naming of the formation from which this megaraptorid was recovered (the Lago Colhué Huapi Formation).

A skeletal reconstruction of the new megaraptor dinosaur species Joaquinraptor casali showing the bones preserved (in blue). Other parts of the skeleton and body outline silhouette are based on closely related species. Photos of many of the preserved bones in various views surround the skeletal reconstruction. Skeletal reconstruction by T.K. Robinson and Andrew McAfee. Picture credit: Lucio M. Ibiricu et al.

Picture credit: Lucio M. Ibiricu et al

The Geologically Youngest Member of the Megaraptoridae

The researchers estimate that Joaquinraptor was around seven metres in length.  It probably weighed a tonne. This newly described theropod is also likely to be the geologically youngest megaraptor ever discovered.  Megaraptors survived until the end of the Cretaceous, 66 million years ago.  The partial, skeleton comes from the Chubut Province (southern Patagonia).  It was studied by Dr Lucio Ibiricu of Argentina’s Instituto Patagónico de Geología y Paleontología, and several other scientists including Dr Matt Lamanna of the Carnegie Museum of Natural History.

Dr Lamanna commented:

“At the Carnegie Museum of Natural History, we’re always seeking to better comprehend the history of life on our planet.  Every year, our team of experts conducts field work all over the world, helping to ensure that we’re on the cutting edge of research.  New revelatory dinosaur discoveries, like Joaquinraptor casali, deepen our understanding of how extraordinary creatures lived and advance understanding of the natural world, both past and present.”

Fossils of the new megaraptor dinosaur species J. casali in the quarry, laying in the positions they had laid for approximately 67 million years. A dentary, teeth, ribs, and several other bones are visible. Picture credit: Marcelo Luna, Laboratorio de Paleontología de Vertebrados Dr. Rubén Martínez, Universidad Nacional de la Patagonia San Juan Bosco.

Picture credit: Everything Dinosaur

An analysis of a cross section of the tibia revealed that this dinosaur was at least nineteen years old when it perished. However, whilst the researchers considered the specimen to have been sexually mature, it was not fully grown.

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

The scientific paper: “Latest Cretaceous megaraptorid theropod dinosaur sheds light on megaraptoran evolution and palaeobiology” by Lucio M. Ibiricu, Matthew C. Lamanna, Bruno N. Alvarez, Ignacio A. Cerda, Julieta L. Caglianone, Noelia V. Cardozo, Marcelo Luna and Rubén D. Martínez published in Nature Communications.

The Everything Dinosaur website: Dinosaur Models.

The thick-skulled, dome-headed pachycephalosaurs are among the most enigmatic and yet, poorly known of all the Dinosauria.  For example, these ornithischians, with their elaborate cranial ornamentation are thought to have evolved complex social behaviours.  After all, the idea that those super thick skulls played a role in butting contests has been around for a long time.  The pachycephalosaurs have a new member.  The recently described Zavacephale rinpoche represents the oldest pachycephalosaur known to science.  It roamed Mongolia around 115 to 108 million years ago.  Its discovery helps palaeontologists to reconstruct the origins and the early evolution of the pachycephalosaurians.

The fossil represents a sub-adult, but the skull already has the distinctive dome. This indicates that pachycephalosaurs developed features relating to combat or display before they reached adulthood. Picture credit: Masato Hattori.

Picture credit: Masato Hattori

Zavacephale rinpoche

The fossil specimen, thought to represent a sub-adult, was discovered in the Khuren Dukh locality of the Eastern Gobi Basin. Not only is the specimen the oldest pachycephalosaur known to science, the skeleton is the most complete for this type of dinosaur found to date.

Corresponding author for the study, Lindsay Zanno, an associate research professor at North Carolina State University commented:

“Pachycephalosaurs are iconic dinosaurs, but they’re also rare and mysterious.”

The fossil material was found by Tsogtbaatar Chinzorig (Mongolian Academy of Sciences), the lead author of the study published in the journal “Nature”. The Z. rinpoche specimen was not fully grown when it died. However, it already bore a fully formed dome, though without much of the additional ornamentation found on other pachycephalosaur fossils.  The genus name is derived from zava which means “root” or “origin” in Tibetan and “cephal” which translates from Latin meaning head. The species name is derived from the Tibetan phrase for “precious one” as the domed skull was exposed on a cliff like a cabochon jewel.

Lindsay Zanno of the Department of Biological Sciences, (North Carolina State University), highlighting the morphology of the Zavacephale rinpoche skull. Picture credit: Alfio Alessandro Chiarenza.

Picture credit: Alfio Alessandro Chiarenza

Predating All Other Pachycephalosaur Fossils by at Least 14 Million Years

Zavacephale rinpoche pushes back fossil evidence of the frontoparietal dome by at least fourteen million years.  Furthermore, the skeleton, which is more than fifty percent complete, preserves regions of the body not scientifically described in any other pachycephalosaur.  For example, scientists could examine an almost complete tail covered in ossified tendons.  In addition, bones from the hand, a first for a pachycephalosaur, were found.

Intriguingly, the specimen had a gastrolith mass preserved in the stomach region.  These stomach stones suggest an omnivorous diet.  The stones ground up tough plant food to help with digestion.  It had been thought that these dinosaurs were herbivores.  However, recent discoveries such as fang-like teeth had led some researchers to speculate that they were carnivorous ornithischians.  The discovery of these stomach stones lends support to the theory that pachycephalosaurs probably ate both plants and animals, that they were omnivores.

To read a blog post from Everything Dinosaur: Pachycephalosaurus – Was it Carnivorous?

Highlighting the significance of Zavacephale rinpoche Tsogtbaatar Chinzorig stated:

“Z. rinpoche predates all known pachycephalosaur fossils to date by about 15 million years. It was a small animal – about three feet or less than one metre long, and the most skeletally complete specimen yet found.”

Chinzorig added:

“Z. rinpoche is an important specimen for understanding the cranial dome development of pachycephalosaurs, which has been debated for a long time due to the absence of early diverging or pre-Late Cretaceous species and the fragmentary nature of nearly all pachycephalosaurian fossils.”

Calculating the Age of a Dinosaur

A thin slice was carefully removed from a lower leg bone.  This slice was then subjected to histological analysis to calculate the dinosaur’s age when it died.  For the first time, palaeontologists had an almost complete pachycephalosaur skull with associated limb bones to help calculate the growth stage of the skeleton.

Lindsay Zanno explained:

“Pachycephalosaurs are all about the bling, but we can’t use flashy signalling structures alone to figure out what species they belong to or what growth stage they’re in because some cranial ornamentation changes as animals mature. We age dinosaurs by looking at growth rings in bones, but most pachycephalosaur skeletons are just isolated, fragmentary skulls. Z. rinpoche is a spectacular find because it has limbs and a complete skull, allowing us to couple growth stage and dome development for the first time.”

The fossil material has pushed back the fossil record of pachycephalosaurs by at least fourteen million years.  In addition, the research team have a much more complete fossil specimen to study.  Moreover, Zavacephale rinpoche demonstrates that dome heads developed in pachycephalosaurs before they reached adulthood.

Lindsay Zanno quipped:

“If you need to headbutt yourself into a relationship, it’s a good idea to start rehearsing early.”

Late Cretaceous Pachycephalosaurs

Most pachycephalosaur fossils are found in Upper Cretaceous deposits, primarily deposits laid down in the Campanian and Maastrichtian.

Austin the Pachycephalosaurus (P. wyomingensis).

Most specimens have been described based on cranial material.  These dinosaurs were bipedal.  Pachycephalosaurus had five fingers on each hand.  The image above of P. wyomingensis shows the PNSO model – Austin the Pachycephalosaurus.  This figure has been widely praised for its accuracy.

To view the range of PNSO models and figures in stock: PNSO Age of Dinosaurs Models.

An Important Discovery

The researchers stressed the significance of this fossil discovery.  Lindsay Zanno stated:

“This specimen is a once-in-a-lifetime discovery. It is remarkable for being the oldest definitive pachycephalosaur, pushing back the fossil record of this group by at least 15 million years, but also because of how complete and well-preserved it is. Z. rinpoche gives us an unprecedented glimpse into the anatomy and biology of pachycephalosaurs, including what their hands looked like and that they used stomach stones to grind food.”

Chinzorig added:

“The newly recovered materials of Z. rinpoche, such as the hand elements, the stomach stones (gastroliths), and an articulated tail with covered tendons, reshape our understanding of the paleobiology, locomotion, and body plan of these ‘mysterious’ dinosaurs.”

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

The scientific paper: “A domed pachycephalosaur from the early Cretaceous of Mongolia” by Tsogtbaatar Chinzorig, Ryuji Takasaki, Junki Yoshida, Ryan T. Tucker, Batsaikhan Buyantegsh, Buuvei Mainbayar, Khishigjav Tsogtbaatar and Lindsay E. Zanno published in the journal Nature.

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

The Sedgwick Museum in Cambridge has an exhibit that tells the remarkable story of the eurypterid Megarachne servinei. It was once thought to be a giant spider. However, it has been assigned to the Mycteroptidae family within the Euryptreida Order. In a recent blog post we looked at the eurypterid display at the Museum.  In particular we commented upon the enormous Jaekelopterus rhenaniae, which is regarded as being one of the largest invertebrates known to science.

To view our earlier post about the giant Jaekelopterus rhenaniae and the eurypterid exhibit: A Colourful Eurypterid Size Chart.

In the exhibit highlighting giant invertebrates, a series of posters provide visitors with information how the palaeo-reconstruction artist Bob Nicholls worked with the researchers to create an interpretation of the fossil material. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Megarachne servinei

The genus name translates as “giant spider”.  If the original scientific assessment had proved to be correct, then M. servinei would be the biggest spider known to science.

Part of this display explains how renowned palaeo-reconstruction artist Bob Nicholls worked with researchers to produce an accurate life reconstruction of this ancient South American invertebrate.

The life reconstruction of Megarachne servinei on display at the Sedgwick Museum (Cambridge). This illustration was created by talented palaeoartist Bob Nicholls. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Mike from Everything Dinosaur commented:

“Palaeoart brings long-extinct creatures back to life. The Megarachne servinei is a fine example. By combining science with illustration, it helps people visualise how these animals looked and lived. As a result, complex fossil evidence, which is often fragmentary becomes easier to understand.”

The Everything Dinosaur website: Dinosaur Models and Prehistoric Animal Figures.

Mike and Sue from Everything Dinosaur recently visited the Sedgwick Museum in Cambridge. During their trip, they spotted a colourful eurypterid size chart on display. It immediately caught their attention.

A largest eurypterid size chart on display at the Sedgwick Museum (Cambridge). The Devonian freshwater eurypterid Jaekelopterus rhenaniae is the largest discovered to date and perhaps the biggest invertebrate of all time. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The Eurypterid Size Chart

The size chart shows seven different eurypterids.  The smallest is Megarachne servinei which is known from the Late Carboniferous of Argentina.  When it was described, it was thought to be a spider. As such, it would have been the largest spider known to science. However, several eurypterids were much bigger.  For example, the largest eurypterid in the diagram, indeed possibly the largest invertebrate of all time is Jaekelopterus rhenaniae.

The stunning 1:20 scale CollectA Deluxe Jaekelopterus rhenaniae model. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

The picture (above) shows the CollectA Deluxe 1:20 scale Jaekelopterus rhenaniae figure. It is a spectacular model.

To view the range of CollectA Deluxe figures in stock: CollectA Deluxe Scale Models.

“Sea Scorpions”

Eurypterids, also known as sea scorpions, are fascinating creatures. Scientists have described around 250 different species. They were active predators. Using their chelicerae, they hunted invertebrates and even primitive fish.

At first, all eurypterids lived in the sea. They were entirely marine. However, things began to change over time. By the Late Devonian and Carboniferous, freshwater species had evolved.

The story of their discovery is also remarkable. In 1818, the very first eurypterid fossil came to light in New York State. At the time, it was thought that this fossil represented an early fish.

Mike from Everything Dinosaur commented:

“The Sedgwick Museum offers a fantastic experience. Its collection includes extremely important fossil discoveries. In addition, visitors find it far less crowded than the London Natural History Museum.”

The Everything Dinosaur website: Dinosaur Toys and Models.

Two remarkable juvenile Pterodactylus fossils have helped researchers to solve a puzzle concerning the Upper Jurassic deposits at Solnhofen. The Upper Jurassic Solnhofen archipelago of Germany has yielded a pterosaur assemblage that has long underpinned and continues to dominate much of our understanding of these Mesozoic flying reptiles.  Pterosaur fossils from this location broadly fit into two categories.  Firstly, there are the highly fragmentary fossils of adult, or sub-adults.  Often a specimen is represented by a single bone.  Secondly, there are the numerous very young pterosaurs* that are preserved almost intact and articulated.

A detailed analysis of two remarkable hatchling Pterodactylus fossils has helped scientists to put forward a plausible theory as to why these two types of fossil preservation, driven by ontogeny occurred.  They postulate that these two baby pterosaurs perished in a violent storm.  Young pterosaurs were caught in powerful tropical storms. Ironically, these powerful storms also created the ideal conditions to preserve their remains and hundreds more.

A hatchling Pterodactylus caught in a storm. Picture credit: Rudolf Hima.

Picture credit: Rudolf Hima

The Mystery of the Hatchling and Juvenile Pterodactylus Specimens

The researchers, including scientists from the University of Leicester discovered broken humeri in the fossilised remains of two hatchling pterosaurs.  These very young flying reptiles suffered broken wings.  The cause of death for these pterosaurs nicknamed “Lucky I” and “Lucky II” by the researchers, has been revealed.  Consider this a post-mortem on events that took place in the Late Jurassic around 150 million years ago.

Writing in the academic journal “Current Biology”, the team highlight that the preservation bias for large, more robust specimens was turned on its head in the waters of the Solnhofen lagoon.  Small delicate animals such as a juvenile Pterodactylus would rarely make it into the fossil record.  However, occasionally nature conspires to produce the conditions that permit the preservation of diminutive pterosaurs.

Lead author of the paper, Rab Smyth (University of Leicester) explained:

“Pterosaurs had incredibly lightweight skeletons. Hollow, thin-walled bones are ideal for flight but terrible for fossilisation. The odds of preserving one are already slim and finding a fossil that tells you how the animal died is even rarer.”

Examining the Tiny Fossils Under UV Light

Examination of the tiny fossils under UV light revealed the presence of broken upper arm bones (humeri) in the two specimens.  These details, easily overlooked, provided the evidence that their wings were subjected to a strong twisting force.  This was probably caused by a strong gust of wind rather than a collision against a hard surface.

Broken bones offer clues to the perils of pterosaur flight. Skeletal reconstructions of the two Pterodactylus hatchlings are shown in flight position, with broken bones marked in red. UV images reveal clear breaks in the upper arm bones. A silhouette of a house mouse (Mus musculus) is included for scale. Picture credit: Smyth et al (University of Leicester).

Picture credit: Smyth et al (University of Leicester)

The picture (above) shows fossil specimen MBH 250624-07 (Lucky I) as (A) part and (B) counterpart.  They are photographed under UV light.  The broken left humerus is in a predominantly ventral view, with the skull exposed in lateral view. Images C and D show the part and counterpart of Lucky II (SNSB-BSPG 1993 XVIII 1508 a/b), photographed in ventral view.  The fossil has a fractured right humerus.

Skeletal reconstructions of Lucky I (E) and Lucky II (F) along with a silhouette of a house mouse (Mus musculus) to provide scale.

Highlighting how Local Environmental Conditions can Distort the Fossil Record

The skeletons are virtually complete and articulated. Except for one small detail. Both specimens show the same unusual injury – a clean, slanted fracture to the humerus. Lucky’s left wing and Lucky II’s right wing were both broken in a way that suggests a powerful twisting force.  The researchers postulate that these unfortunate flying reptiles were caught up in a storm.

Pterosaur fossil preservation in the Solnhofen deposits. (A) Most of the time, pterosaurs stood little chance of becoming fossils. Decaying larger individuals sometimes left behind scattered bones that reached the lagoon floor, but smaller pterosaurs were usually lost without trace. (B) Storms, however, created very different conditions. Powerful winds and waves dragged the bodies of small and young pterosaurs into deeper waters. At the same time, these storms stirred up salty water from the lagoon floor. This water contained almost no oxygen, and when it mixed with the surface waters, it triggered sudden die-offs of marine life. These toxic waters acted as a barrier to scavengers and decay, allowing pterosaur bodies to sink largely untouched. The final step came when lime-rich mud, carried by the storm, rapidly buried the remains. This quick covering not only protected soft tissues from decay but also preserved fragments of larger pterosaurs that had been deposited earlier. Together, these rare conditions explain why fossils from Solnhofen are so well preserved. Picture credit: Smyth et al (University of Leicester).

Picture credit: Smyth et al (University of Leicester)

Catastrophically injured, the pterosaurs plunged into the surface of the lagoon, drowning in the storm driven waves and quickly sinking to the seabed where they were rapidly buried by very fine limy muds stirred up by the violent storm events. This rapid burial allowed for the remarkable preservation seen in their fossils.  The researchers have highlighted how local environmental conditions can lead to distortions in the fossil record.

Ironic Names for Juvenile Pterodactylus Fossils

Lucky I and Lucky II are ironic nicknames for these pterosaur fossils.  These animals may only have been a few days or weeks old when they perished.  There are many other small pterosaurs preserved in the Solnhofen limestone deposits.  These too, might present very young flying reptiles.  They may not demonstrate obvious signs of skeletal trauma but they could have met a similar fate as Lucky I and Lucky II. Unable to resist the strength of storms these young pterosaurs were also flung into the lagoon. This discovery may explain why smaller fossils are so well preserved – they were a direct result of storms – a common cause of death for pterosaurs that lived in the region.

Larger, stronger individuals, it seems, were able to weather the storms and rarely followed the Luckies stormy road to death. They did eventually die though but likely floated for days or weeks on the now calm surfaces of the Solnhofen lagoon, occasionally dropping parts of their carcasses into the abyss as their bodies slowly decomposed.

Rab Smyth added:

“For centuries, scientists believed that the Solnhofen lagoon ecosystems were dominated by small pterosaurs. But we now know this view is deeply biased. Many of these pterosaurs weren’t native to the lagoon at all. Most are inexperienced juveniles that were likely living on nearby islands that were unfortunately caught up in powerful storms.”

The researchers conclude that catastrophic storm sampling explains the high numbers of small, potentially juvenile pterosaurs preserved in the Solnhofen deposits.  This study also has implications for the perceived flight abilities of very young flying reptiles.  Wing injuries in neonatal pterosaurs were likely caused by violent storm events and this research supports precocial flight ability.

A “Lucky” Break

Co-author of the paper, Dr David Unwin (University of Leicester) commented:

“When Rab spotted Lucky we were very excited but realised that it was a one-off. Was it representative in any way? A year later, when Rab noticed Lucky II we knew that it was no longer a freak find but evidence of how these animals were dying. Later still, when we had a chance to light-up Lucky II with our UV torches, it literally leapt out of the rock at us – and our hearts stopped. Neither of us will ever forget that moment.”

*very young pterosaurs – there is some debate over whether the fossils all represent hatchlings or very young animals.  In addition, describing these two specimens as representatives of the taxon Pterodactylus has drawn criticism.  It has been suggested that this study could have included a detailed phylogenetic analysis rather than assign the two fossil specimens to what has been referred to as a “taxonomic wastebasket”.

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

The scientific paper: “Fatal accidents in neonatal pterosaurs and selective sampling in the Solnhofen fossil assemblage” by Robert S.H. Smyth, Rachel Belben, Richard Thomas and David M. Unwin published in Current Biology.

The award-winning Everything Dinosaur website: Everything Dinosaur.

Scientists including researchers from the Museum für Naturkunde (Berlin) have identified the oldest leaf mines in the fossil record. In addition, evidence of insect egg deposits has been found in association with these ancient trace fossils. Insect trace fossils in the studied fossil materials are so abundant that the researchers state that this is the oldest evidence of an insect infestation known to science.  The plant fossils examined in this ground-breaking research come from several museum collections.  The trace fossils record the highly specialised behaviour of insect larvae that lived approximately 295 million years ago.

The research, published in the journal “Scientific Reports” indicates that this specialised feeding behaviour had evolved at least forty million years earlier than previously thought.

The oldest leaf mines (Asteronomus maeandriformis) known to science. A plant fossil from the Permian period collected in Thuringia (left). Leaf mines of the leaf miner fly Liriomyza on a sow thistle (right). Picture credit: Laaß et al (Museum für Naturkunde Berlin).

Picture credit: Laaß et al (Museum für Naturkunde Berlin)

The Advantages of Being a Leaf Miner

In the late spring and summer evidence of the activity of insect larvae feeding inside the leaves of plants is easy to find. The insects produce distinctive channels in the surface of the leaf. Living inside plant tissue has many advantages. For example, the larvae are protected from predators, and they are less prone to harmful infections. In addition, they avoid dehydration, and the larvae have an almost inexhaustible supply of food all around them.

Today, leaf mines are produced exclusively by insects such as beetles, dipterans (flies), wasps and butterflies.  They undergo complete transformation (metamorphosis) and are therefore referred to as holometabolous insects. Holometabolous insects have four stages:

• Egg
• Larva
• Pupa
• Adult

Holometabolous insects are highly adaptable and extremely numerous. They have evolved slender, maggot-like larvae without body appendages that are optimally adapted to life inside plant tissue.

Until now, it was unclear when this sophisticated and highly successful strategy emerged in the Insecta. Previously, the oldest reliable evidence of leaf mines came from plant fossils from the Triassic.  This new study identifies for the first time leaf mining in Palaeozoic fossils.  These oldest leaf mines highlight the importance of conserving museum collections.

The Oldest Leaf Mines

The researchers from the natural history museums in Berlin, Chemnitz, Münster and Osnabrück, the TU Bergakademie Freiberg and Martin Luther University Halle-Wittenberg have been able to prove, leaf mining behaviour occurred more than forty million years earlier than previously thought. The extensive plant fossil collections from the natural history museums in Schleusingen, Berlin and from the Freiberg University collection were examined. These collections contained numerous exceptionally well-preserved specimens of the feeding traces of Asteronomus maeandriformis on leaves of the seed fern Autunia conferta.

The plant fossils come from the coal fields in Crock, Thuringia. These deposits, representing ancient swamps, were laid down in the Early Permian. Close scrutiny of the specimens permitted the team to conclusively prove leaf mining behaviour. In addition, the team identified many of the egg deposits associated with the feeding tunnels, which in some cases even contained the remains of insect eggs.

Numerous types of plants today have extremely ancient lineages.  For example, horsetails (Equisetum) continue to thrive as they are able to grow in areas where other plants would find it difficult to get a foothold. Often regarded as weeds, these tough little plants are essentially living fossils as the earliest examples of the genus Equisetum date from the Early Jurassic of South America. Picture credit: Everything Dinosaur.

Picture credit: Everything Dinosaur

Over Eighty Percent of the Fossil Autunia Plants Infested

Evidence of leaf mining was found in more than eighty percent of all the fossilised Autunia plants from Thuringia studied.

Palaeobotanist Ludwig Luthardt, one of the co-authors of the paper stated:

“Why exactly the Autunia plants in Crock were infested en masse remains largely a mystery. However, the phenomenon occurred at a time of global change, during which tropical terrestrial ecosystems gradually became drier. This shows how important it is to look to the past in times of current global climate change.”

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

The scientific paper: “Host-specific leaf-mining behaviour of holometabolous insect larvae in the early Permian” by Michael Laaß, Ludwig Luthardt, Steffen Trümper, Angelika Leipner, Norbert Hauschke and Ronny Rößler published in Scientific Reports.

The Everything Dinosaur website: Prehistoric Animal Models and Figures.