Weewarrasaurus pobeni – Hints at Different Kinds of Dinosaur Communities

The fortuitous discovery of pieces from the lower jaw of a small, plant-eating dinosaur is helping scientists to discover more about the Cretaceous dinosaurs that once roamed Australia.  Writing in the academic journal “PeerJ”, the researchers provide evidence to support the idea that there were numerous small-bodied ornithopods at high latitudes in south-eastern Australia, whilst further north, in what would have been slightly warmer environments, these types of dinosaurs co-existed with much bigger ornithopods and titanosaurs.

The dinosaur has been named Weewarrasaurus pobeni (pronounced wee-whah-rar-sore-us poe-ben-eye) and it is the first new dinosaur to be described from New South Wales for nearly 100 years.

A Life Reconstruction of the Newly Described Gondwanan Ornithopod Weewarrasaurus pobeni

Picture credit: James Kuether

A Lucky Fossil Find

Adelaide-based opal buyer Mike Poben spotted the fossil pieces in a bucket of opal rubble from the Wee Warra opal field at Lightning Ridge (New South Wales, Australia).  The dinosaur was named in honour of the location and the trivial name recognises the contribution of Mr Poben who donated the specimens for research.

Numerous opalised dinosaur fossils are known from the Lightning Ridge area.  The material, including fragments of bones and isolated teeth come from the Griman Creek Formation.  Recent radiometric dating indicates that these deposits are around 100 to 96 million years old (Cenomanian stage of the Late Cretaceous), making these rocks some 10 million years younger than equivalent exposures containing dinosaur fossils found in northern Queensland.

The Fossil Jaw Fragments (Right Dentary) of Weewarrasaurus pobeni

Picture credit: PeerJ

Unfortunately, the underground mining process involves breaking up the rocks, so any specimens found tend to consist of isolated broken pieces, however the presence of a scalloped-shaped tooth in the object immediately caught the attention of Mr Poben, so he was able to quickly appreciate that this was part of a jawbone.  Lightning Ridge is the only place in the world where dinosaur bones and teeth routinely turn to opal.  Corresponding author of the scientific paper, Dr Philip Bell (University of New England), explained that researchers were now looking into acquiring more fossil material from opal mines.

Dr Bell stated:

“Unfortunately, the fossil remnants we see are almost always part of mining spoil… but on another hand, we would never get to see even those fragments if it wasn’t for mining.”

Opal Helps to Identify a Dinosaur

One of the benefits of the presence of opal in the fossil is that the distinctive banding pattern formed helped the scientists to identify that the two fossil pieces belonged to the same jawbone.

Views of the Jawbone Fossil (Weewarrasaurus pobeni)

Picture credit: PeerJ/Dr Bell (University of New England)

The picture above shows three views of the fossils, (A), medial; (B), dorsal; and (C) lateral views.   The dashed black line shows the outline of the missing pieces that would have comprised a more substantial part of the dentary.  The dashed red lines indicate the distinctive banding pattern in the opal used to estimate the extent of the missing area.  Another jawbone fragment (LRF 766), representing a right dentary with teeth in situ from the nearby Three Mile opal field has also been assigned to this new dinosaur species.

Faunal Differences in Different Regions of Prehistoric Australia

The Griman Creek Formation fossils from Lightning Ridge indicate that there were numerous small Ornithopods living in this environment during the Cenomanian stage of the Late Cretaceous.  This research provides further evidence to support previous studies that favour a general abundance of small-bodied basal Ornithopods in high-latitude localities of south-eastern Australia.  These little dinosaurs, most of which were under two metres in length, inhabited a verdant flood plain, but this part of the Gondwana was at approximately 60 degrees south.  Today, Australia is much further north, the city of Sydney (New South Wales), is located at approximately 33.86 degrees south.  During the Cretaceous, the dinosaurs that inhabited the part of Australia we now call New South Wales, would have had to endure periods of darkness in the year when the sun dipped below the horizon, although the presence of ectothermic reptiles such as crocodyliforms and turtles indicate that average minimum temperatures may not have fallen below 5 degrees Celsius.

Even so, the climate may have been too extreme for sauropods.  Cretaceous deposits in Queensland (Winton Formation), have revealed several titanosaurs, but the colder temperatures experienced further south may have limited sauropod distribution.

The researchers conclude that although future dinosaur fossil discoveries have the potential to alter these interpretations, it is suggested that the Griman Creek Formation at Lightning Ridge occupied a “meeting point” between more northern sauropod-dominated faunas and the ornithopod-dominated faunas that existed further south.

Computer Generated Images from Fossil Scans Helped to Identify Ornithopod Characteristics

Picture credit: PeerJ

To read a recent article about an opalised dinosaur toe bone found in South Australia: Lost Dinosaur Toe Bone Turns Up on the Internet.

Visit the award-winning Everything Dinosaur website: Everything Dinosaur.

Toe Bone Turns Up on the Internet

A rare dinosaur bone, one of only three dinosaur fossils known from the state of South Australia, is going on display at the South Australian Museum some forty-five years after it was lost to science.  The opalised bone, representing a single toe bone (phalanx), is believed to come from a type of theropod dinosaur and although named Kakuru kujani, which was officially described from opalised remains representing lower leg bones back in 1980, very little is known about this Cretaceous dinosaur.

The toe bone was found in Andamooka in the far north of South Australia sometime in the early 1970s.  It was spotted for sale in an opal shop in Hindley Street, Adelaide by Neville Pledge, the South Australian Museum’s then curator of fossils, in 1973.  Neville had the foresight to take several photographs, measurements and plaster casts of the toe bone.  However, shortly afterwards, the item was sold and it disappeared from the scientific community.

The Opalised Toe Bone on Display at the South Australian Museum

Picture credit: Ashleigh Glynn

The Tale of a Dinosaur Toe Bone

In April 2018, the bone was spotted up for sale on the internet by Coober Pedy resident Joy Kloester, who purchased the bone and then offered it to the South Australian Museum.  The Museum’s Senior Collections Manager for Earth Sciences, Ben McHenry acted quickly to acquire the specimen for the vertebrate palaeontology department.

Mr McHenry commented:

“I couldn’t believe our luck in finding the same bone after forty-five years.”

Dinosaur bones from South Australia are extremely rare.  The only two other bones known to science found to date are also part of the vertebrate fossil collection of the South Australian Museum.  During the Early Cretaceous period (around 110 million years ago, Albian fauna stage), when dinosaurs roamed the land, most of South Australia was under water, being part of the ancient Eromanga Sea.  The sediments deposited on the floor of this ancient sea now form the rocks of the Great Artesian Basin and preserve the abundant remains of marine life that can be viewed in the Museum’s Opal Fossil gallery.

This special dinosaur toe bone will be on display in this gallery from today (December 3rd).  Neville Pledge is now an Honorary Researcher at the South Australia Museum, it seems his discovery from 45 years ago, has now joined him at this highly respected institution.

What Sort of Dinosaur was Kakuru kujani?

Kakuru kujani (pronounced: Kah-koo-roo koo-yan-eee), is believed to be about the size of a turkey.  Unfortunately, given the limited fossil material, it is not possible to identify its taxonomic position with the Theropoda.  K. kujani was described from fragmentary lower leg bones (tibia and possible fibula fragments), the toe bone may not belong to this genus at all, but given the lack of other candidates, the Museum has assigned the bone to Kakuru.

It has been postulated that this dinosaur was an oviraptorid, although some affinity to the Abelisauridae has also been proposed.  Its formal classification remains Theropoda incertae sedis, which means it has an uncertain placement within this Suborder.

A Speculative Reconstruction of Kakuru kujani

Picture credit: South Australian Museum

Everything Dinosaur acknowledges the assistance of a press release from the South Australian Museum in the compilation of this article.

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Lisowicia bojani Huge Dicynodont from the Late Triassic of Poland

The Late Triassic of southern Poland was home to a giant “mammal-like” reptile the size of an elephant and weighing some 9 tons.  Scientists from the Polish Academy of Sciences in collaboration with colleagues from Uppsala University (Sweden), have published details on the discovery of the fossilised remains of a huge therapsid, specifically a dicynodont, that has been named Lisowicia bojani.  This super-sized, distant ancestor of modern mammals is believed to have measured around 4. 5 metres in length and stood more than 2.6 metres tall.

A Life Reconstruction of the Newly Described Giant Dicynodont Lisowicia bojani

Picture credit: Karolina Suchan-Okulska

More than 1,000 Bones Recovered from a Clay Pit

The first fossil remains were found by Polish geologists Robert Borzęcki and Piotr Menducki in 2005, when they were exploring a clay pit which represented a river deposit from the Upper Triassic.  The dig site is close to the village of Lisowice, numerous field teams have been despatched to the area and over the last few years, more than 1,000 bones and bone fragments have been collected, including the fossilised remains of a giant dicynodont.  At first the scientists thought they had discovered the fossils of a sauropod, but soon it was realised that the large and robust bones represented a therapsid.

The genus name is in honour of the nearby village, whilst the trivial name honours the German comparative anatomist Ludwig Heinrich Bojanus.

Field Team Members Excavated Fossils from the Clay Pit (Silesia, southern Poland)

Picture credit: Dr Grzegorz Niedzwiedzki (Uppsala University)

Lisowicia bojani – Defining Dicynodonts

Dicynodonts (die-sigh-no-donts), are a group of extinct, synapsids which evolved during the Permian period.  These quadrupeds were herbivorous and belong to the Order Therapsida, which includes modern mammals.  It had been thought that by the Late Triassic, these animals had died out, the discovery of L. bojani from strata estimated to be around 210-205 million years old indicates that they persisted into the Late Triassic in Europe.  The fossilised remains of Lisowicia are at least ten million years younger than any previously described dicynodont fossil material.

Commenting on the discovery, Dr Tomasz Sulej (Polish Academy of Sciences) and one of the researchers involved in this study, stated:

“The discovery of Lisowicia changes our ideas about the latest history of dicynodonts, mammal Triassic relatives. It also raises far more questions about what really make them and dinosaurs so large.”

The Massive and Very Robust Limb Bones of Lisowicia bojani

Picture credit: Dr Grzegorz Niedzwiedzki (Uppsala University)

CollectA have produced a scale model of Lisowicia bojani: CollectA Deluxe Prehistoric Life.

The discovery of Lisowicia provides the first evidence that mammal-like elephant sized dicynodonts were present at the same time as the more well-known long-necked Sauropodomorpha dinosaurs, contrary to previous belief.  Lisowicia fills a gap in the fossil record of dicynodonts and it shows that some anatomical features of limbs thought to characterize large mammals or dinosaurs evolved also in the non-mammalian synapsid.  Furthermore, these findings from Poland are the first substantial finds of dicynodonts from the Late Triassic in Europe.  Lisowicia is at least 40% bigger than any known dicynodont.

A Skeletal Drawing of Lisowicia bojani (Note Scale Bar)

Picture credit: Dr Tomasz Sulej (Polish Academy of Sciences)

Commenting on the significance of the fossil find, Dr Tomasz Sulej remarked:

“The discovery of such an important new species is a once in a lifetime discovery.”

Visit the Everything Dinosaur website: Everything Dinosaur.

Macrocollum itaquii – Oldest Long-necked Sauropodomorph is Described

A team of scientists based in Brazil have described the fossilised remains of three Triassic dinosaurs that lived some 225 million years ago that shed light on the evolution of long-necks in plant-eating dinosaurs.  The new species, a member of the Sauropodomorpha, has been named Macrocollum itaquii, the genus name comes from the Greek for “long neck”, an appropriate moniker for a prehistoric animal that is helping to unravel the developmental history of the long-necked dinosaurs bauplan.

Macrocollum itaquii

Although Macrocollum is estimated to have measured about four metres in length and weighed approximately 100 kilograms, a lot smaller than later sauropods, some of which were the largest terrestrial animals to have ever lived, it is considerably bigger than older dinosaur fossil specimens found in South America, some of the earliest dinosaurs known, that lived around ten million years earlier and represent some of the very first dinosaurs to evolve.

A Life Reconstruction of Macrocollum itaquii

Picture credit: SWNS

The Rise of the Sauropodomorpha

Despite a number of recent fossil discoveries, palaeontologists have a relatively poor understanding of the rise of the sauropodomorphs, a group that includes some of the most famous of all the dinosaurs, giants such as Diplodocus and Brachiosaurus.

The fossil material, representing three individuals, was collected from the upper portion of the  Candelária Sequence of the Paraná Basin, from a site in Agudo, Rio Grande do Sul (southern Brazil).  Nearby strata have been dated to the Norian faunal stage of the Late Triassic.  Writing in the academic journal “Biology Letters”, the researchers, which included biologist Rodrigo Müller from the Federal University of Santa Maria (Brazil), conclude that these three animals died together and therefore provide the oldest evidence of herding behaviour in sauropodomorphs described to date.

The proposal that the three individuals died together and as such, indicate gregarious behaviour, has been challenged by a number of academics.  It is possible that these three herbivores died at different times and the carcases just happened to be transported and ended up in association.

Commenting upon this, Rodrigo Müller explained:

“There are three articulated skeletons in five tons of rock.  This is unique.  It suggests these animals probably died together, as they share the same degree of disarticulation.  So, if they died together, these dinosaurs probably lived together.”

Long Necks and Long Thigh Bones

Two of the specimens include skull material, the holotype (CAPPA/UFSM (Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia) 0001a), is virtually complete and articulated.  It is one of the best preserved Triassic dinosaur skeletons ever found.  With such exceptionally well-preserved specimens the scientists have been able to conduct an analysis looking at how the long-neck of these types of dinosaurs evolved and study the femur (thigh bone), length to give an indication in the change of body size since the first plant-eating dinosaurs evolved.  In addition, these fossils have shed light on how these animals adapted to a fully herbivorous diet.

Macrocollum Fossil Material Has Helped Shed Light on Important Evolutionary Developments within the Sauropodomorpha

Picture credit: R T Müller et al in Biology Letters

The table above shows the phylogenetic position attributed to the newly described M. itaquii.  Based on this assessment it has been assigned to the Unaysauridae family, basal members of the Sauropoda, that are known from Triassic-aged rocks from the Southern Hemisphere (India and South America).  The discovery of Macrocollum has helped palaeontologists to gain a better understanding of the evolution of the long-neck of sauropods.  The cervical vertebrae (neck bones) of M. itaquii are already much more elongated than seen in earlier representatives of the Sauropodomorpha known from around 233 million years ago.  The teeth are more spatulate in shape, indicating an adaptation to a plant-eating diet and over this 8 million year period (233-225 million years ago), femora measurements demonstrate that sauropodomorphs increased in size by 230%.

Views of Skull Material Associated with M. itaquii

Picture credit: R T Müller et al in Biology Letters

The typical long neck was also established,  becoming proportionally twice as long than those necks of basal taxa.  Indeed, the new dinosaur is the oldest-known sauropodomorph with such an elongated neck, suggesting that the ability to feed on high vegetation was a key trait achieved along the early Norian.

Skeletal Reconstruction and Significant Bones Including Elongated Cervical Vertebrae

Picture credit: R T Müller et al in Biology Letters

The species name honours Mr José Jerundino Machado Itaqui, one of the main drivers behind the creation of the Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia and the Federal University of Santa Maria.

To read about the recent discovery of an Early Jurassic sauropod from China (Yizhousaurus sunae), that is helping palaeontologists to learn more about how some types of dinosaur were able to evolve into giants: Helping to Give Sauropod Evolution a Head Start.

To read about a giant Late Triassic sauropodomorph (Ingentia prima): Triassic Dinosaur Just Got a Lot Bigger.

The scientific paper: “An Exceptionally Preserved Association of Complete Dinosaur Skeletons Reveals the Oldest Long-necked Sauropodomorphs” by Rodrigo Temp Müller, Max Cardoso Langer and Sérgio Dias-da-Silva published in Biology Letters.

Visit the Everything Dinosaur website: Everything Dinosaur.

An Oregon Ornithopod

There may be many famous dinosaurs known from the United States of America, after all, when it comes to naming dinosaurs, Tyrannosaurus rex, Stegosaurus and Triceratops tend to trip off the tongue, but America’s dinosaur fossil heritage is not uniform across the whole country.  Several parts of the U.S. have no record of dinosaur discoveries, and numerous others have a very fragmentary record when it comes to the preserved remains of Dinosauria.  Oregon, the ninth largest State in terms of area, has a very poor dinosaur fossil record, however, a newly described fossil discovery made in the eastern part of the “Beaver State”, has got palaeontologists quite excited about the prospect of more dinosaur fossil finds being made.

The Toe Bone from a Dinosaur (Ornithopoda)

Writing in the “Journal of Vertebrate Palaeontology”, scientists from the University of Oregon in collaboration with the University of Calgary (Canada), have published a paper on the discovery of a single toe bone from a plant-eating dinosaur – an extremely rare find considering that this part of north-western North America was underwater throughout most of the Mesozoic Era.

Various Views of the Single Dinosaur Toe Bone (Pedal Phalanx)

Picture credit: University of Oregon

The fossil bone was found by University of Oregon Earth Sciences Professor Greg Retallack during field work in 2015, near the town of Mitchell (Wheeler County, eastern Oregon).  The single bone was spotted amongst mollusc fossils exposed on a slope consisting of marine shale.  The fossil dates from the Albian fauna stage of the Cretaceous and is the first ever Oregon dinosaur fossil to be the subject of a paper in a peer-reviewed scientific journal.  Furthermore, it represents the first dinosaur fossil find from Oregon from strata not regarded as Upper Cretaceous.

Oregon might be bigger than the whole of the United Kingdom, but the Mesozoic-aged exposures represent marine sediments, that harbour very few remains of ancient terrestrial animals.

Greg Retallack stated:

“Oregon landscapes are rich with Cretaceous rocks, but they rarely contain the kinds of dinosaur remains we see elsewhere in the United States.  The rocks here are the right age but are mostly from under the sea where dinosaurs did not live or from swamps where dinosaur bones are seldom preserved.”

Not Able to Assign a Genus

Although, identified as a dinosaur bone (pedal phalanx), it is not possible to assign it to a specific species or genus, although the research team are confident that it came from a plant-eating ornithopod dinosaur.

An Illustration of a Typical Ornithopod Dinosaur

Picture credit: Edyta Felcyn

Co-author of the paper, Edward Davis (University of Oregon), explained that the remains of a terrestrial animal ended up in the mollusc bed, after having been swept out to sea.

He explained:

“It’s a phenomenon we sometimes call “bloat and float”.  That is, the animal died on shore in its terrestrial habitat, then was washed out to sea, where it floated while bloated with decomposition gasses.  Eventually it burst, and only this toe bone was entombed and became a fossil.”

A Sizeable Plant-eating Dinosaur

Although very little taxonomic information can be gained from a single, isolated toe bone, a size comparison with much more complete and better known Cretaceous ornithopods such as Tenontosaurus, suggests that this dinosaur may have been about six to seven metres long and weighed around a tonne.

A spokesperson from Everything Dinosaur commented:

“Although such a fossil find in marine sediments is exceptionally rare, it just goes to show that dinosaurs fossils can be found and if there is one, then there may be more. Many of the Mesozoic-aged rocks in this part of Oregon represent near coastal marine deposits.  Given that dinosaurs would have roamed the land close to the sea for millions of years it is possible that more dinosaur remains might be found.”

To read an article published by Everything Dinosaur in 2015, which looks at which part of the United States are not associated with dinosaur fossils: Washington State the 37th U.S. State with a Dinosaur.

Visit the Everything Dinosaur website: Everything Dinosaur.

Lavocatisaurus agrioensis – A New Long-Necked Dinosaur from Argentina

A team of palaeontologists from Argentina and Spain have announced the discovery of a new species of long-necked dinosaur from the Early Cretaceous of Argentina.  The dinosaur, represented by a set of bones that indicate the remains of at least three individuals, has been named Lavocatisaurus agrioensis and it will help to shed more light on a rare and enigmatic group of sauropods known as the rebbachisaurids.

A Skeletal Reconstruction and Photographs of Key Fossils from L. agrioensis

Picture credit: AFP/Agencia CTYS

The picture above shows the skeletal drawing of the adult dinosaur with illustrations of key bones from the excavation.  Most of the neck and the skull has been recovered.  Cranial fossils associated with the Rebbachisauridae are rare, the discovery of these specimens from Agrio del Medio (Neuquén Province, Argentina) will help scientists to better understand taxonomic relationships amongst members of this sauropod family, largely associated with Gondwanaland fossil deposits.

Fossils of a Family Group?

Writing in the journal “Acta Palaeontologica Polonica”, the scientists report the discovery of one large, presumably adult animal with two smaller sub-adults found in association.  The fossil material come from terrestrial sandstone deposits laid down around 110 million years ago (Aptian to Albian faunal stage of the Early Cretaceous), in an arid environment with isolated oasis and other water sources (Rayoso Formation).

One of the authors of the scientific paper, José Luis Carballido, of the Egidio Feruglio Museum (Argentina), stated:

“We found most of the cranial bones: the snout, the jaws, a lot of teeth, also the bones that define the eye sockets for example and in that way, we were able to create an almost complete reconstruction.  Not only is this the discovery of a new species in an area where you wouldn’t expect to find fossils, but the skull is almost complete.”

Lavocatisaurus agrioensis

The fossils represent one large dinosaur estimated to be around twelve metres in length and two smaller animals around six to seven metres in length.  The research team postulate that this could represent a family group that lived together and perished together, perhaps unable to find a water source in a time of drought.

Preparing to Move Some of the Fossil Material (Lavocatisaurus)

Picture credit: AFP/Agencia CTYS

Lead author of the paper, José Ignacio Canudo (Zaragoza University, Spain) added:

“This discovery of an adult and two juveniles also signifies the first record of a group displacement among the Rebbachisaurus dinosaurs.”

The Rebbachisauridae Family

The Rebbachisauridae family of sauropods are a group of basal members of the Diplodocimorpha clade that includes more famous Late Jurassic dinosaurs such as Diplodocus, Apatosaurus and Brontosaurus.  The rebbachisaurids are known from both Lower Cretaceous and Upper Cretaceous strata and had a wide geographical distribution throughout Gondwana and southern Laurasia with fossils reported from north and central Africa as well as South America and Europe (Spain).

An Illustration of a Typical Rebbachisaurid Dinosaur (R. garasbae)

Picture credit: Everything Dinosaur

Visit the Everything Dinosaur website: Everything Dinosaur.