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/Dinosaur and Prehistoric Animal News Stories

Fossil finds, new dinosaur discoveries, news and views from the world of palaeontology and other Earth sciences.

13 07, 2019

Microraptor Ate Lizards

By | July 13th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles|0 Comments

Stomach Contents Reveal New Species of Early Cretaceous Lizard

Scientists writing in the academic journal “Current Biology”, have described a new specimen of Microraptor (M. zhaoianus) from Liaoning Province (north-eastern China), that preserves the remains of a small lizard in its body cavity.  The remains of the lizard, inside what would have been the stomach of this little feathered dinosaur, are largely intact and articulated.  This indicates that the unfortunate lizard was swallowed head first, a feeding behaviour seen in extant carnivorous birds and many small reptiles.  The fossilised bones of the lizard represent a new species, it has been named Indrasaurus wangi.

Microraptor is now known to have fed on a variety of small vertebrates, supporting the interpretation that it was an opportunistic predator.

Microraptor About to Swallow the Unfortunate Indrasaurus

Microraptor feeds on Indrasaurus.

A life reconstruction of a Microraptor consuming the lizard Indrasaurus.  The position of the lizard’s remains inside the body cavity of Microraptor indicate that the lizard was swallowed head first.

Picture Credit: Doyle Trankina

Direct Evidence of Predator-Prey Interactions from the Jehol Biota

Direct evidence of diet and predator-prey relationships are extremely rare in the fossil record.  However, the exceptional preservation conditions associated with the Liaoning deposits have resulted in four examples of stomach contents in Microraptor specimens having been identified.  Microraptor is now known to have been a generalist, eating a variety of small vertebrates including  mammals, birds, fish, and with this new discovery, lizards.

Photograph of the Microraptor Specimen (STM5-32) Preserving the Lizard Indrasaurus wangi in the Body Cavity

Microraptor ate lizards.

The Microraptor fossil specimen (STM5-32) the white box indicates location of lizard remains.

Picture Credit: O’Connor et al (Current Biology)

The white lines in the photograph indicate the body cavity area of the Microraptor and show the location of the lizard fossil remains.  The genus name Indrasaurus comes from Hindu scriptures in which the deity Indra was swallowed by the dragon Vritra during their battle.  The species (trivial name), honours Yuan Wang, for his extensive work on the Jehol Biota and his assistance in helping to promote Chinese fossils through museum events and exhibitions.

An Interpretative Line Drawing Showing the Remains of Indrasaurus (I. wangi) in the Abdominal Cavity

The remains of the lizard inside the Microraptor.

A line drawing showing the remains of the lizard Indrasaurus wangi within the stomach cavity of a Microraptor (M. zhaoianus).

Picture Credit: O’Connor et al (Current Biology)

The interpretative drawing (above), shows the contents within the white box outlined in the specimen (STM5-32).  Analysis of the lizard’s bones indicate that it was probably a sub-adult when it met its doom.  Ironically, the Microraptor itself died shortly after eating the lizard, although this would probably have not been much comfort to Indrasaurus had it known this at the time.

Most scientists believe that Microraptor could fly, it is not known whether this little lizard was caught in a tree or captured on the ground after a terrestrial pursuit.  Perhaps Microraptor swooped down onto its prey from a lofty vantage point, a tactic common to many carnivorous birds today.  The probable troodontid Anchiornis from the older Late Jurassic Yanliao Biota is roughly the same size as Microraptor and fossils of Anchiornis reveal that this dinosaur ate lizards too.  However, comparison of the fossilised remains of prey suggests that dromaeosaurids such as Microraptor ingested prey that were fully digested, whereas, Anchiornis may have regurgitated undigested body parts, bringing up a pellet as demonstrated in many bird species alive today.  This feeding behaviour supports a closer relationship between true birds and Anchiornis and suggests that powered flight did not precipitate the evolution of pellet regurgitation (egestion), in these reptiles.

The scientific paper: “Microraptor with Ingested Lizard Suggests Non-specialized Digestive Function by Microraptor with Ingested Lizard Suggests Non-specialized Digestive Function” by Jingmai O’Connor, Xiaoting Zheng, Liping Dong, Yan Wang, Xiaomei Zhang and Zhonghe Zhou published in the journal “Current Biology”.

12 07, 2019

New Theropod Dinosaur from the Late Triassic of Switzerland

By | July 12th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Notatesseraeraptor frickensis – A Mixture of Coelophysid and Dilophosaurid Characteristics

A new European theropod dinosaur from the Late Triassic of Switzerland has been named and described this week.  This is big news, as very little is known about Late Triassic theropods that roamed Europe more than 200 million years ago, only a handful have been described to date, just four species.  The dinosaur has been named Notatesseraeraptor frickensis (No-tah-tess-er-ray-rap-tor frick-ensis), the genus name derives from the Latin “nota” meaning feature and “tesserae”, a Latin term to describe tiles used to create a mosaic, a reference to the mixture of anatomical features (dilophosaurid and coelophysoid) identified in the fossil bones. The trivial name honours the Swiss town of Frick, where the fossils were found.

The Body Plan, Known Fossil Material and a Skeletal Reconstruction of N. frickensis

Skeletal anatomy of Notatesseraeraptor frickensis

The silhouette shows the body plan of Notatesseraeraptor, known fossil material and pictures of the blocks that make up the holotype specimen.

Picture Credit: Nature: Ecology and Evolution

Lizard-eating Dinosaur

The partially articulated specimen was collected in 2006 from the famous Gruhalde clay pit in the town of Frick (Aargau Canton, northern Switzerland).  This clay pit has yielded large numbers of Plateosaurus fossils, although Notatesseraeraptor layer is located above the classic Plateosaurus bone beds.  The strata are from the middle part of the Gruhalde Member of the Klettgau Formation and represents Late Triassic (end-Norian) sediments.  The fossils associated with N. frickensis include a nearly complete skull, articulated forelimbs, vertebrae, hip bones and ribs.  The body cavity revealed the remains of a Clevosaurus, a lizard-like rhynchocephalian, distantly related to the extant Tuatara of New Zealand.  It is likely that the Clevosaurus remains represent this dinosaur’s last meal.

The Skull of Notatesseraeraptor frickensis

Notatesseraeraptor frickensis cranial material.

A view of the skull and upper jaw (Notatesseraeraptor frickensis).  Around 90% of the cranial fossil material was recovered.

A Carnivorous Dinosaur Reported from Switzerland

Around 90% of the skull material was excavated, giving Notatesseraeraptor one of the most complete carnivorous dinosaur skulls known from before the Late Jurassic.   Although, our knowledge of early theropod dinosaurs has improved greatly since the turn of the century, thanks mainly to fossil discoveries from North and South America, very little is known about the evolution and radiation of Late Triassic/Early Jurassic European theropods, their fossil record is notably sparse.  This new theropod species is the first meat-eating dinosaur to be described from Switzerland.

Notatesseraeraptor displays a mix of characteristics typically seen either in coelophysids or in dilophosaurids.  A phylogenetic analysis suggests that it is a member of the Neotheropoda clade with affinities to Dilophosaurus of the Early Jurassic and that Notatesseraeraptor is a basal member of that line of theropods that led to the Averostra (a group, of carnivorous dinosaurs that includes the Ceratosaurs).

The Late Triassic/Early Jurassic European Theropods

The nearly complete skull will help palaeontologists to better understand the evolutionary relationships between different types of Late Triassic/Early Jurassic theropod dinosaur.  The fossil specimen suggests a sub-adult with a length of between 2.6 to 3 metres, but this is speculation based on comparative analysis with dinosaurs such as Coelophysis and Tawa as the length of the tail of Notatesseraeraptor is not known.

A Life Reconstruction of a Typical Coelophysid Dinosaur (Coelophysis bauri)

Coelophysis model.

A life reconstruction of Coelophysis bauri.

Picture Credit: Everything Dinosaur

The three previously described species of Late Triassic European theropod are:

  • Liliensternus liliensterni – named in 1934 (von Huene) from the Middle and Late Norian of Germany
  • Procompsognathus triassicus – named in 1913 (Fraas) also from the Middle to Late Norian of Germany
  • Lophostropheus airelensis named in 1993 known from slightly younger rocks (Late Rhetian to Hettangian – Late Triassic to possibly Early Jurassic)

With the exception of a few scraps of bone associated with Liliensternus skull material and the recently described  Dracoraptor hanigani from south-Wales, no other skull material has been found relating to a neotheropod dinosaur from the Late Triassic/Early Jurassic  in the whole of Europe.

11 07, 2019

Terrestrial Bird-like Dinosaur Oldest Known from North America

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Hesperornithoides miessleri – Helping to Map Out the Bird Family Tree

A joint team of British and American palaeontologists have announced the discovery of a new species of dinosaur that roamed the Late Jurassic of Wyoming.  The specimen consisting of both cranial and postcranial material lived around 150 million years ago and it has been tentatively placed within the troodontid branch of the Paraves part of the Theropoda.  It could help scientists to better understand the evolutionary relationships between feathered dinosaurs and true birds and it raises intriguing questions as to when powered flight evolved within the Dinosauria.

The little dinosaur, estimated to have measured less than a metre in length (single known specimen is either an adult or a sub-adult), has been named Hesperornithoides miessleri.

A Life Reconstruction of the Newly Described Dinosaur H. miessleri

Hesperornithoides miessleri - life reconstruction.

A life reconstruction of Hesperornithoides miessleri.

Picture Credit: Gabriel Ugueto

An Inhabitant of Wetlands

Writing in the academic journal PeerJ, the authors which include scientists from the University of Manchester, report the taphonomy of the fossil material suggests that this dinosaur was an inhabitant of wetland environments for at least a portion of its life history.  The fossil material was actually discovered back in 2001, whilst excavation work was being carried out on the fossil material associated with Supersaurus.  The fossil comes from Converse County (Wyoming), from strata making up the middle portion of the famous Morrison Formation.  The fossil-bearing strata from the “Jimbo Quarry” has been variously dated to the Oxfordian and Tithonian ages of the Jurassic.

Full Skeleton of Hesperornithoides miessleri

Known fossil material associated with Hesperornithoides miessleri.

Hesperornithoides fossil material “left” (A) and “right” (B) sides of the blocks after final preparation (B).  Scale bar = one cm.

Picture Credit: Levi Shinkle

A Resident of the Famous Morrison Formation

The Morrison Formation is famous for its vertebrate fossils, including many examples of dinosaurs, such as Allosaurus, Ceratosaurus, Diplodocus, Brontosaurus and Camarasaurus.  The carnivorous Hesperornithoides is the smallest dinosaur described to date from Wyoming.

Palaeontologist Bill Wahl  (Wyoming Dinosaur Centre), a co-author of the scientific paper, recalled how excited the field team were when they uncovered the block containing the partially articulated bones.

He stated:

“We were removing a ledge of overburden rock and found, unfortunately with a shovel, some tiny, delicate bones poking out.  We immediately stopped, collected as much of the bones as possible and spent the next few days frantically searching for more.  Only after some of the bones were cleaned did we realise that we had found something spectacular.”

In 2005, the fossil specimen was donated to the Big Horn Basin Foundation, a research and education-based not-for-profit organisation that was merged with the Wyoming Dinosaur Centre back in 2016.  This is how Hesperornithoides miessleri came into the Wyoming Dinosaur Centre’s fossil collection.  The fossil, now known as WYDICE-DML-001, was nicknamed “Lori”  and was examined by Dean Lomax (University of Manchester) and co-author of the study back in 2008, a successful crowdfunding campaign permitted extensive research to be undertaken.

Dean commented:

“I remember the first time I laid my eyes on this little dinosaur.  Even back then, I knew it was a significant discovery.  But, it wasn’t until 2015 when our dino team formed and we began to study ‘Lori’ in much more detail than ever before.”

Reconstructed Quarry Map of “Lori” (Hesperornithoides miessleri)

A quarry map of the fossil material asociated with Hesperornithoides.

Association of skeletal elements assembled from 3-D scans of specimen blocks prior to final mechanical preparation.

Picture Credit: PeerJ

Found on Private Land

The specimen was found on private land owned by the Miessler family.  The trivial name honours their help, support and assistance in bringing this little theropod to the attention of the scientific community.  The genus name is a combination of “Hesper”, referring to its discovery in the American West and “ornis” a nod to its very bird-like anatomy.

A Reconstruction of the Skeleton of Hesperornithoides miessleri

Hesperornithoides miessleri skeleton reconstruction.

Skeletal Reconstruction Hesperornithoides miessleri (scale bar = 25 cm).

Picture Credit: Scott Hartmann

A Key Conclusion of the Study

A key conclusion of the scientific paper relates to the origin of powered flight within the Dinosauria.  Hesperornithoides was very probably entirely terrestrial.  It could not fly, but it has a very bird-like body, suggesting that many features associated with an avian anatomy evolved in dinosaurs that lived out their lives on the ground.  It is the oldest dinosaur of this type, known from more than just teeth fossils from North America.  The terrestrial and flightless lifestyle is consistent with the base of Paraves, and with the base of paravian subclades, suggesting that avian flight evolved within the Avialae, most likely in the Late Jurassic or Early Cretaceous.

Lead author of the paper and PhD student at the University of Wisconsin-Madison, Scott Hartman stated:

“We wanted to expand the dataset used to test dinosaur-bird relationships, so we added hundreds of new species and tens of thousands of new characters.  We found that Lori is a primitive member of a group of dinosaurs that includes Troodon, but perhaps more importantly we discovered that the smaller details of the family tree of bird-like dinosaurs isn’t quite as resolved as some researchers would claim.”

Scott Hartman continued:

“For example, it only takes a few changes in the dataset for Hesperornithoides to be found as a closer relative of Velociraptor than of Troodon.  One robust finding we did come up with is that even as the interrelationships changed, the primitive members of all these groups were non-flying ground dwelling dinosaurs.  That means that some small relatives of Velociraptor such as Microraptor that looks like it could have glided evolved this separately from the modern bird family.”

Hesperornithoides Cranial Material

Fossil material and accompanying line drawings Hesperornithoides.

Hesperornithoides cranial material and interpretative line drawings.

Picture Credit: Levi Shinkle

The scientific paper: “A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight” by Hartman, S., Mortimer, M., Wahl, W. R., Lomax, D. R., Lippincott, J. and Lovelace, D. M and published in PeerJ.

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

5 07, 2019

Repeated Evolution of Herbivorous Crocodyliforms

By | July 5th, 2019|Animal News Stories, Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Fossil Teeth Suggests Lots of Different Types of Mesozoic Crocodiles

Researchers from the University of Utah have studied the teeth of extinct crocodyliforms and concluded that crocodiles occupied a large range of different ecological niches during the Age of Dinosaurs.  Furthermore, these geographically widespread and speciose reptiles adapted to a variety of diets and that herbivorous crocodyliforms evolved at least three times independently.  This suggests that plant-eating was a beneficial dietary strategy and not a unique occurrence.  Many of these crocodyliforms lived alongside omnivorous or herbivorous synapsids, illustrating an ecological partition that is not found today.

The Diets of Extinct Crocodyliforms were Diverse with Many Examples of Herbivory Identified

Extinct crocodyliforms had different shaped teeth.

Life reconstructions of extinct crocodyliforms. Differences in tooth shape are related to differences in diets.

Picture Credit: Jorge Gonzalez

Writing in the academic paper “Current Biology”, the researchers Keegan Melstrom and Randall Irmis at the Natural History Museum of Utah at the University of Utah, discovered that multiple ancient groups of crocodyliforms (the group including living and extinct relatives of crocodiles and alligators), were not all carnivorous.  Research has been conducted before on the various potential dietary niches of ancient crocodiles, but this new study proposes that vegetarianism arose at least three times within this group.

Commenting on the significance of this new study, doctoral student Keegan Melstrom stated:

“The most interesting thing we discovered was how frequently it seems extinct crocodyliforms ate plants.  Our study indicates that complexly shaped teeth, which we infer to indicate herbivory, appear in the extinct relatives of crocodiles at least three times and maybe as many as six.”

Teeth Variation within Crocodyliforms (Extinct and Extant)

Heterodonty in Crocodyliforms.

False colour 3-D images showing the range in shape of crocodyliform teeth.  Carnivores (left), such as the living Caiman, have simple teeth, whereas herbivores (right) have much more complex teeth.

Picture Credit: Keegan Melstrom (The Natural History Museum of Utah)

The Tip of the Crocodyliform Iceberg

The twenty plus species of crocodylians alive today possess a similar general body shape and ecology.  They are mainly generalist hypercarnivores and semi-aquatic, confined to lower latitudes.  Although, consuming fruit and vegetable matter has been observed in several extant species.  In 2013, Everything Dinosaur wrote an article about fruit consumption (frugivory), in crocodiles.

To read the article: New Study Suggests a Number of Different Types of Crocodylian Consume Fruit.

The crocodiles alive today, all have similar, simple conical teeth but the fossil record shows that extinct crocodyliforms were much more diverse.  Today’s crocodiles are just the remnants from a once much richer and more specious group of reptiles, consider the living crocodylians as the “tip of the crocodyliform iceberg”.

Living Crocodiles are Generalist Ambush Predators (Hypercarnivores)

Saltwater crocodile (Estuarine crocodile).

A Saltwater crocodile (Crocodylus porosus), the largest living reptile which is an apex predator (hypercarnivore).

The researchers identified different teeth morphologies (heterodonty) and this suggests that in the past crocodile-like creatures had a variety of diets.

Melstrom added:

“Carnivores possess simple teeth whereas herbivores have much more complex teeth.  Omnivores, organisms that eat both plant and animal material, fall somewhere in between.  Part of my earlier research showed that this pattern holds in living reptiles that have teeth, such as crocodylians and lizards.  So, these results told us that the basic pattern between diet and teeth is found in both mammals and reptiles, despite very different tooth shapes, and is applicable to extinct reptiles.”

Keegan Melstrom (The Natural History Museum of Utah) with Some of the Casts Used in the Study

Examing three-dimensional prints of fossil jaws.

Keegan Melstrom, the study’s lead author, with the fossil jaw of Brachychampsa and 3-D prints of other extinct crocodyliforms (blue).

Picture Credit: The Natural History Museum of Utah

Comparing Tooth Complexity – Extinct versus Extant

To deduce what long dead crocodyliforms most likely consumed, Melstrom with the assistance of his graduate advisor ( Randall B. Irmis), compared the tooth complexity of extinct crocodyliforms to those of living animals using a research methodology originally designed to study mammalian heterodonty.  In total, 146 teeth from 16 different species of extinct crocodyliforms were incorporated into the study.

Using a combination of quantitative dental measurements and an assessment morphological features, the scientists reconstructed the diets of those extinct animals.  The results indicate that these animals had a wider range of dental complexities and presumed dietary ecologies than had been appreciated previously.  Quantitative analyses also revealed that some species with complex dentition were likely to be herbivorous.

The researchers conclude that plant-eating crocodyliforms appeared early in the group, perhaps shortly after the end-Triassic mass extinction event and herbivory persisted until the end of the Age of Dinosaurs.  The analysis suggests that herbivory arose independently a minimum of three times, and possibly six times, in Mesozoic crocodyliforms.

Melstrom stated:

“Our work demonstrates that extinct crocodyliforms had an incredibly varied diet.  Some were similar to living crocodylians and were primarily carnivorous, others were omnivores and still others likely specialised in eating plants.  The herbivores lived on different continents at different times, some alongside mammals and mammal relatives, and others did not.  This suggests that herbivorous crocodyliforms were successful in a variety of environments!”

As many of these herbivorous crocodyliforms co-existed with plant-eating synapsids including Mammaliaformes, some of which were the ancestors of today’s mammals, this was an ecological partition that is no longer found on our planet.

The scientific paper: “Repeated Evolution of Herbivorous Crocodyliforms during the Age of Dinosaurs” by Keegan M. Melstrom and Randall B. Irmis published in Current Biology.

Everything Dinosaur acknowledges the assistance of a press release from the University of Utah in the compilation of this article.

28 06, 2019

The First Dinosaur from the Caiuá Group (Brazil)

By | June 28th, 2019|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Vespersaurus paranaensis – A Desert Dwelling Dinosaur

Roaming the Late Cretaceous of Brazil some 90 to 85 million years ago, was a little, fast-running, carnivorous dinosaur with a unique way of getting about.  The dinosaur has been named Vespersaurus paranaensis and at an estimated length of just over a metre (maximum length 1.6 metres), this was no giant, but its discovery will help scientists to work out the taxonomic relationships amongst an obscure group of theropods known mainly from Gondwana and provide new insight into theropod locomotion.

Writing in the academic journal “Scientific Reports”, the researchers suggest that Vespersaurus supported its weight on just one digit (metatarsal III and toe III), it may have been essentially monodactyl i.e. it had one main, central weight-bearing toe.  The other toes associated with support and weight bearing in the Theropoda (digits II and IV), were very much smaller and may even have been held off the ground.

A Life Reconstruction of the Newly Described Brazilian Theropod Vespersaurus paranaensis

Vespersaurus life reconstruction.

A life reconstruction of the Brazilian dinosaur Vespersaurus.

Picture Credit: Rodolfo Nogueira

Affinities with the Abelisauroidea

Analysis of the fossil material, which includes vertebrae, elements from the pelvis and limbs along with fragmentary skull bones suggests that this little dinosaur is a member of the Abelisauroidea, specifically the Noasaurinae, an enigmatic subfamily collectively known from sparse fossil material mostly from southern latitudes.  For example, Vespersaurus has the reduced forelimbs which are characteristic of the abelisaurids and it is hoped that these fossils will help palaeontologists to better understand the phylogeny of these Late Cretaceous predators.  Although only about 40% of the skeleton is known, these fossils represent one of the best examples of a member of the Noasauridae family found to date and the most complete dinosaur specimen from the whole of the Bauru Sub-basin.  It is also the first dinosaur to be described from rocks that constitute part of this basin, the Caiuá Group.

Frontal (Skull Bone) and Views of an Isolated Tooth (Vespersaurus paranaensis)

A skull bone and an isolated tooth (Vespersaurus paranaensis).

Cranial and dental remains of Vespersaurus paranaensis, an isolated frontal and an isolated broken tooth.

Picture Credit: Scientific Reports (Langer et al)

A Late Cretaceous Desert Environment

The majority of the strata making up the Caiuá Group represent sandstones that were deposited by the action of wind (aeolian deposits).  During the Late Cretaceous, this region of Gondwana was an extensive desert.  The fossil record is particularly sparse with only a handful of animals recorded from what probably would have been oases.  Arguably, the most famous fossils from this part of the world represent a pterosaur monodominant bonebed (Caiuajara dobruskii).  Other than Caiuajara and this new dinosaur, the only other vertebrate fossils known from this area represent a lizard and a turtle.

Pectoral Elements and Limb Bones (V. paranaensis)

Front limb bones and elements from the pectoral girdle (Vespersaurus paranaensis).

Pectoral girdle and limb elements of Vespersaurus paranaensis.

Picture Credit: Scientific Reports (Langer et al)

To read about Caiuajara: New Species of Flying Reptile Identified from Pterosaur Graveyard

Strange Footprints

Examination of the foot bones and toes suggests that this dinosaur supported its weight on just a single, central digit.  Such an anatomical adaptation (a monodactyl stance), has not been recorded in the Archosauria before, but such a form of locomotion had been inferred by palaeontologists as numerous footprints indicating an enlarged weight-bearing toe in a theropod dinosaur have been found in rocks of the same age as the sediments that yielded the fossils of Vespersaurus.

A Close Up of the Foot Showing the Weight-bearing Toe

The foot of Vespersaurus

A close-up view of the foot of Vespersaurus showing the weight-bearing central toe.  Footprints suggesting a monodactyl stance have been found in the same stratigraphic unit that yielded the new dinosaur.

Video image credit: Universidade de Sáo Paulo et al

Helping to Classify the Noasaurinae

The Noasaurinae are a branch of the Abelisauroidea consisting of small, predatory theropods known from Upper Cretaceous strata mostly associated with Gondwana (southern latitudes).  Perhaps the best known noasaurid is Masiakasaurus knopfleri, from the latest Cretaceous (Maastrichtian) of Madagascar, but two other taxa from Argentina described from relatively fragmentary fossil material have been assigned to the Noasaurinae (Noasaurus leali and Velocisaurus unicus).  Other dinosaurs from outside South America have also been tentatively assigned such as an as yet, unnamed specimen from India, Deltadromeus agilis from Morocco and Genusaurus sisteronis from France.  It is hoped that this more complete fossil specimen will permit palaeontologists to better understand taxonomic relationships within the Noasaurinae and their wider placement within the Abelisauroidea.

Building a Family Tree of the Abelisauroidea

Classifying Vespersaurus.

Vespersaurus is assigned to the Noasaurinae, a sub-family of the Abelisauroidea clade of theropods.  The suggested position of Vespersaurus is shown by the red dinosaur silhouette.

Picture Credit: Scientific Reports (Langer et al)

Etymology of Vespersaurus

The generic name derives from the words “vesper” (Latin for evening/west) and “sauros” (Greek for lizard/saurian), in reference to the name of the town Cruzeiro do Oeste (Western Cross), where the fossils were found.  The specific epithet refers to the Paraná state, the authors report that V. paranaensis represents the first non-avian dinosaur from that area of Brazil.

The scientific paper: “A new desert-dwelling dinosaur (Theropoda, Noasaurinae) from the Cretaceous of south Brazil” by Max Cardoso Langer, Neurides de Oliveira Martins, Paulo César Manzig, Gabriel de Souza Ferreira, Júlio César de Almeida Marsola, Edison Fortes, Rosana Lima, Lucas Cesar Frediani Sant’ana, Luciano da Silva Vidal, Rosangela Honório da Silva Lorençato and Martín Daniel Ezcurra published in the journal Scientific Reports.

21 06, 2019

A New Species of Australian Prehistoric Crocodile is Announced

By | June 21st, 2019|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Isisfordia molnari – A New Species of Australian Crocodile from the Cretaceous

Researchers from the University of New England (New South Wales), Queensland University and the Australian Opal Centre have described a new species of prehistoric crocodile.  The Cretaceous-aged croc has been named Isisfordia molnari, it is the second species described within the Isisfordia genus, both are known from Australia, although I. duncani, which was named in 2006, heralds from the Winton Formation of Queensland, whilst the new species I. molnari, comes from the geologically younger Griman Creek Formation of New South Wales.

A Life Reconstruction of the Newly Described Prehistoric Crocodile Isisfordia molnari

Isisfordia life reconstruction.

Isisfordia molnari life reconstruction.  A wading Sauropod has nothing to fear from I. molnari.

Picture Credit: José Vitor Silva

Honouring Ralph Molnar

The trivial name honours vertebrate palaeontologist Ralph Molnar, in recognition of his contribution to the research on crocodylomorphs from Gondwana.  Molnar was one of the researchers responsible for the naming of Isisfordia duncani back in 2006.  The new species has been erected based on a partial braincase and a fragment of jawbone (maxilla).  Both fossils have been opalised and come from the Lightning Ridge area, but their exact provenance remains uncertain.  The fossil jaw fragment had previously been designated as the holotype of Crocodylus (Bottosaurus) selaslophensis, but has, following a review, been assigned to this new species.  This piece of jawbone complete with six teeth in situ had been donated to the Australian Museum in 1914.  The partial braincase is probably a much more recent find, it was purchased by the Australian Museum in the early part of this century.

Photographs and Line Drawings of the Braincase of Isisfordia molnari

Isisfordia molnari braincase.

Photographs and line drawings of the braincase of Isisfordia molnari.  (A, B) dorsal, (C, D) ventral, (E, F) caudal, (G, H) rostral, (I, J) right lateral and (K, L) left lateral views.

Picture Credit: PeerJ

The Fragment of Upper Jawbone Assigned to the Newly Erected Species (I. molnari)

Jaw fragment (Isisfordia molnari).

A fragment of jawbone now assigned to Isisfordia molnari.  Arrows indicate rostral end ((A) medial, (B) lateral, (C) palatal views).

Picture Credit: PeerJ

The scientific paper: “Isisfordia molnari sp. nov., a new basal eusuchian from the mid-Cretaceous of Lightning Ridge, Australia” by Lachlan J. Hart, Phil R. Bell, Elizabeth T. Smith and Steven W. Salisbury published in PeerJ.

17 06, 2019

Dinosaur “Fossil Wall” Discovered in South-western China

By | June 17th, 2019|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Treasure Trove of Dinosaur Fossils Discovered

Reports have been circulating from a number of Chinese media outlets concerning the discovery of an extensive fossil bed containing the remains of numerous dinosaurs in southwest China’s Chongqing Municipality.  The fossil site has been known about for several years but there have been a number of reports this week circulating, hinting at the extent of the fossil discovery and indeed, suggesting that it is very likely that as a result of excavation work, new species of dinosaur will be named and described.

An Extensive Dinosaur Bonebed

Mapping and excavating a fossil site.

Excavating an extensive fossil deposit.

Picture Credit: VCG

The photograph (above), shows a Chinese field team member working on the “wall of dinosaur fossils”.  The site of the fossil find is described as a location close to Laojun village, Pu’an town, in Yunyang county.

New Dinosaur Species

The press reports state that scientists have identified different types of dinosaurs including theropods and basal ornithopods.  The disarticulated remains represent a bone accumulation and the strata is reported to be around 174 million years old (Aalenian faunal stage of the Middle Jurassic).  Commentators have described these fossil beds as very significant and likely to lead to the naming of new dinosaur species.

An Illustration of a Typical Basal Ornithopod

A typical ornithopod.

A typical example of a basal ornithopod.

Picture Credit: Everything Dinosaur

Four Thousand Individual Fossil Pieces

The mixed fossil assemblage has already provided researchers with around 4,000 pieces of dinosaur bone to study, since the site was first explored and mapped in 2017.

A spokesperson from Everything Dinosaur commented:

“The site has been described as exceeding 150 metres in length with at least 17 distinct assemblages of fossils within it.  Not much is known about the dinosaur biota from the earliest stages of the Middle Jurassic.  Once all the bones have been removed, prepared and studied it is very likely that several new species of dinosaur will be announced.  These dinosaurs will help palaeontologists to map the radiation and dispersal of several key groups of dinosaurs that were to dominate terrestrial ecosystems for the remainder of the Jurassic.”

The Famous Dinosaur Monument (Utah)

The famous Dinosaur Monument (Utah).

The Dinosaur Monument (Utah).

The extensive fossil material could become China’s equivalent of America’s Dinosaur Monument in Utah.  The Dinosaur Monument represents a congregation of dinosaur fossils that accumulated in a river deposit.  Whilst similarities can be drawn between the two sites, the Chongqing Municipality deposits are approximately 25 million years older.

Perhaps, this could be China’s second “Great Wall”.

16 06, 2019

Biggest Elasmosaur Known to Science

By | June 16th, 2019|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Giant Elasmosaurs from Antarctica

An scientific paper published in the academic journal “Cretaceous Research” details the remarkable discovery of a huge elasmosaurid plesiosaur from Upper Cretaceous deposits located on Seymour Island in Antarctica.  The specimen, ascribed to the Aristonectes genus is estimated to have measured around 11 metres in length and could have weighed as much as fifteen tonnes.   The strata from which the fossil material was collected is believed to have been laid down towards the end of the Cretaceous, thus this fossil discovery indicates that very large elasmosaurs were around towards the very end of the Mesozoic.

A Life Reconstruction of a Typical Elasmosaurid Marine Reptile

A typical Elasmosaurus model.

Late Cretaceous elasmosaurid from Seymour Island (Antarctica).

Picture Credit: Everything Dinosaur

Seymour Island – Helping to Map Marine Fauna at the Very End of the Cretaceous

The exposed sediments on the inhospitable and remote Seymour Island provide palaeontologists with the opportunity to study life that existed at the very end of the age of dinosaurs and the sequence of exposed rocks covers the transition from the end Cretaceous extinction event into the Palaeogene.  The occurrence of this specimen, located approximately 2.3 metres or less below the Cretaceous-Palaeogene (K/Pg) boundary, suggests the persistence of these types of plesiosaurs (aristonectines), at high latitudes and also it verifies their chronostratigraphical distribution until the end Cretaceous, before the mass extinction the resulted in the loss of all marine reptiles with the exception of marine turtles.

This is not the first giant, marine reptile to be found on Seymour Island…

To read an article from 2016 which describes the discovery of the remains of a giant Mosasaur marine reptile in Maastrichtian-aged deposits on Seymour Island: An Apex Marine Predator from the Late Cretaceous of Antarctica

The fossil material (MLP 89-III-3-1), consisting of disarticulated post-cranial elements most probably representing an individual animal, comes from the uppermost Maastrichtian levels of the López de Bertodano Formation, Seymour Island (sometimes referred to as Marambio Island), Antarctica.  The research team members conclude that this specimen is amongst the largest elasmosaurids known.

A field team found the first evidence of this animal back in 1989, but at the time, the team lacked the resources to excavate the specimen.  Subsequent expeditions to the fossil site in 2005, 2012 and 2017 led to the removal of some 800 kilograms of fossil bones.

Large Elasmosaurids Thrived in High Latitudes at the End of the Cretaceous

Elasmosaur persisted at high latitudes.

Elasmosaurs illustrated.  Large elasmosaurids persisted at high latitudes (Antarctica and within the Arctic Circle).

Picture Credit: James Havens

Co-author of the scientific paper, José O’Gorman of the National Scientific and Technical Research Council of Argentina, commented that for years the researchers were not sure whether the fossils represented an elasmosaurid or something else, the animal is described as a “weird plesiosaur.”

The large size of this specimen coupled with the giant mosasaur fossils known from this locality suggest that these waters were highly productive and able to support a variety of megafauna.  These conditions are likely to have persisted until the K/Pg mass extinction.  Although, the animal has not been given a formal, binomial scientific name, the researchers conclude that it has affinities with the Aristonectinae, a sub-family within the Elasmosauridae.

The scientific paper: “A giant elasmosaurid (Sauropterygia; Plesiosauria) from Antarctica: New information on elasmosaurid body size diversity and aristonectine evolutionary scenarios” by
J.P. O’Gorman, S. Santillana, R. Otero and M. Reguero published in the journal Cretaceous Research.

15 06, 2019

Don’t Get “Sniffy” About Dinosaur Sense of Smell

By | June 15th, 2019|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Tyrannosaurs Had Their Noses in Front When it Came to Sense of Smell

A team of scientists from University College Dublin have built upon the idea put forward in earlier research indicating that many dinosaurs such as Tyrannosaurus rex had an impressive sense of smell.  In a recently published paper, the scientists examined the sense of smell of a wide range of living and extinct archosaurs and concluded that many different dinosaurs had an excellent olfactory sense but the Tyrannosaurs probably had one of the keenest senses of smell amongst the Dinosauria.

New Study Confirms T. rex Had a Powerful Sense of Smell

T. rex dinosaur model

Up close to Tyrannosaurus rex.  It could smell you probably before it could see you.

Picture Credit: Everything Dinosaur

Olfactory Bulb Ratios

The brains of long extinct animals, like most soft tissues, are poor candidates for fossilisation, the size and the shape of an extinct animal’s brain can be inferred by looking at how the skull bones knit together to form the brain case.  It is from this data that the size and the proportion of the brain dedicated to processing sensory data such as the sense of smell can be deduced.  It has been stated in the past that approximately 50% of the brain volume of a T. rex was made up of the olfactory bulb, that part of the brain that processes smells.  Furthermore, in most modern animals, the size of the brain’s olfactory bulb also correlates with how well they can identify odours.  Looking at the ratio between that part of the brain dedicated to processing smells and the size of the entire brain (the olfactory bulb ratio), can also provide evidence as to the ecological niche an animal is likely to have occupied in an ecosystem.

The King of the Tyrant Lizards Top of the Table for Olfactory Abilities Too

T. rex specimen (cast)

Tyrannosaurs had a highly developed sense of smell.

Picture Credit: Everything Dinosaur

For example, a bird that hunts in low light levels using scent to find food, is likely to have adapted to its environment very differently from that of a kestrel that hunts in daylight and uses its keen eyesight to spot its prey.

Writing in the journal “Proceedings of the Royal Society B”, Dr John Finarelli and his colleague Graham Hughes (University College Dublin), used the olfactory bulb ratio in living archosaurs (crocodiles and birds) to infer the strength of smell amongst dinosaurs.

Prior research has shown that the size of the olfactory bulb is related to the number of smell receptor genes in the DNA of a given animal and how much diversity they represent.  Taken together, it is called the olfactory repertoire. In this new study, the researchers used the olfactory repertoire of modern birds and an alligator to estimate the olfactory ability of several types of dinosaurs.  Based on this innovative research, the scientists concluded that T. rex probably had between 620 and 645 genes encoding its olfactory receptors, a gene count only slightly smaller than those in today’s chickens and domestic cats.  Closely related Tyrannosaurs such as Albertosaurus, also had substantial olfactory receptor gene counts.  Tyrannosaurs probably had the best sense of smell amongst the Dinosauria, this in turn can lead to inferences about how these theropods lived and behaved.

For example, Tyrannosaurs were probably able to “sniff out” prey from far away.  They were  able to track down the carcass of another dinosaur and scavenge the corpse.

A Good Sense of Smell Has Many Other Uses in the Animal Kingdom

The researchers hope that this new study will not get drawn into the “T. rex a hunter or a scavenger debate”, the authors stress that a good sense of smell has many other uses other than finding food.  Many animals use scent to mark and define territory, track down a mate, deter rivals and for intraspecific communication.  The University College Dublin scientists also highlighted a shift in scaling of olfactory bulb ratios to body size along the theropod lineage that led to the evolution of modern birds.  The researchers conclude that by combining morphological and genomic data, it can be demonstrated that, while genetic information for extinct taxa is forever lost, it is potentially feasible to investigate evolutionary trajectories in extinct animals.

Amongst Living Vertebrates, It is the Elephant that Tops the Table for the Most Olfactory Receptor Genes

An African elephant model.

An African elephant (Loxodonta).

Picture Credit: Everything Dinosaur

Amongst all living vertebrates, the record for the most olfactory receptor genes lies with the modern elephant, a herbivore with about 2,500 such genes.  With such an exquisite sense of smell, elephants can “count” quantities of food by odour alone.  The researchers looked at a number of different types of dinosaur in their study, sure enough, some plant-eating dinosaurs showed evidence of a greater reliance on smell than some carnivorous dinosaurs.  For example, the Late Cretaceous herbivore Erlikosaurus (E. andrewsi), a theropod but a member of the Therizinosauridae had a greater number of projected olfactory receptor genes than Velociraptor and other predatory dromaeosaurids.

The Research Team Assessed Olfactory Bulb Ratio Compared to Body Mass Amongst Living and Extinct Archosaurs

Olfactory bulb ratios amongst examples of the Archosauria.

Olfactory bulb ratios amongst living and extinct archosaurs.  This new study confirmed earlier research indicating that the Tyrannosaurs had a powerful sense of smell.

Picture Credit: University College Dublin

14 06, 2019

“King of the Trilobites” Discovered in South Australia

By | June 14th, 2019|Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Redlichia rex – Fearsome Predator of Trilobites

A team of scientists have described a new species of trilobite and at around thirty centimetres in length, this new species is the largest member of the Trilobita from Australia to have been described to date.  Writing in the academic publication, the Journal of Systematic Palaeontology, the team consisting of researchers from the University of Adelaide, South Australian Museum and the University of New England describe Redlichia rex and suggest that it probably specialised in attacking and eating smaller trilobites.  It might even have been a cannibal!

Lead author of the research, James Holmes, a PhD student at the University of Adelaide commented:

“We decided to name this new species of trilobite Redlichia rex (similar to Tyrannosaurus rex) because of its giant size, as well as its formidable legs with spines used for crushing and shredding food, which may have been other trilobites.”

A Life Reconstruction of the Newly Described Trilobite Species Redlichia rex

Redlichia rex life reconstruction.

A life reconstruction of the newly described Redlichia rex trilobite.

Picture Credit: Katrina Kenny

Exceptional State of Preservation

The fossil material comes from an exceptional Lagerstätte known as the Emu Bay Shale on Kangaroo Island, South Australia, these sediments represents shallow sea deposits laid down in the  Early Cambrian.  Around fifty different species of trilobite have been described from this location.  Well-preserved, fully articulated specimens from this deposit are known to reach lengths in excess of 25 centimetres, representing one of the largest known Cambrian trilobites.  Until now, all Redlichia specimens from the Emu Bay Shale have been referred to as Redlichia takooensis.

Previous studies recognised considerable differences in exoskeletal shape and morphology among specimens of varying sizes, which were thought to represent different growth stages of the same species (ontogeny).  However, close examination of a large collection of recently acquired specimens shows that this variation actually represents two distinct morphs, interpreted by the researchers as representing a distinct and larger species – Redlichia rex.

PhD Student James Holmes with a Fossil of R. rex

Redlichia rex fossil.

PhD student James Holmes and a fossil specimen of Redlichia rex.

Picture Credit: University of Adelaide

Many of the fossils demonstrated an exceptional state of preservation with soft parts such as the antennae and the legs preserved.  At around 30 centimetres in length, Redlichia rex is almost twice as big as most other Australian trilobites recorded from Cambrian-aged rocks.

Co-study author, Diego García-Bellido, from the University of Adelaide and the South Australian Museum added:

“Interestingly, trilobite specimens from the Emu Bay Shale, including Redlichia rex, exhibit injuries that were caused by shell-crushing predators.  There are also large specimens of fossilised poo (coprolites), containing trilobite fragments in this fossil deposit.  The large size of injured Redlichia rex specimens and the associated coprolites suggests that either much bigger predators were targeting Redlichia rex, such as Anomalocaris – an even larger shrimp-like creature – or that the new species had cannibalistic tendencies.”

Evidence of an Evolutionary Arms Race

The naming of this new species demonstrates the diversity of the marine biota within this ancient sea environment and supports the idea that one of the principle drivers of the “Cambrian explosion” was the evolutionary “arms race” between predators and prey species.  As predators became larger and more efficient hunters, so primary producers and secondary predators developed more effective defences, this in turn led to the evolution of more deadly predator species.

A Fossil Specimen (Redlichia rex)

Redlichia rex trilobite fossil.

A near complete specimen of the large Cambrian trilobite Redlichia rex.

Picture Credit: University of Adelaide

James Holmes commented:

“The overall size and crushing legs of Redlichia rex are a likely consequence of the arms race that occurred at this time.  This giant trilobite was likely the terror of smaller creatures on the Cambrian seafloor.”

Fossils of the amazing Cambrian marine biota including specimens of Redlichia rex are currently on display at the South Australian Museum (Adelaide).

The scientific paper: “The trilobite Redlichia from the lower Cambrian Emu Bay Shale Konservat-Lagerstätte of South Australia: systematics, ontogeny and soft-part anatomy” by James D. Holmes, John R. Paterson and Diego C. García-Bellido published in the Journal of Systematic Palaeontology.

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