Dinosaurs – Species Encycolpedia

Scientists Discover 11th Archaeopteryx Fossil, the Oldest Yet

Saturday, January 27, 2018

The oldest specimen of Archaeopteryx was found in Germany. Photo by O. Rauhut/LMU


Mansourasaurus shahinae: School Bus-sized Dinosaur Fossil Found in Sahara Desert

Wednesday, January 31, 2018

The scientists recovered parts of its skull, lower jaw, neck and back vertebrae, ribs, shoulder and forelimb, back foot and osteoderms. (Image Source: Carnegie Museum of Natural History)

Researchers have found the fossil of a dinosaur in the Sahara Desert, which could help explain the evolution of the animals in the continent.

Scientists have unearthed in a Sahara Desert oasis in Egypt fossils of a long-necked, four-legged, school bus-sized dinosaur that lived roughly 80 million years ago, a discovery that sheds light on a mysterious time period in the history of dinosaurs in Africa.

Researchers said on Monday the plant-eating Cretaceous Period dinosaur, named Mansourasaurus shahinae, was nearly 33 feet (10 meters) long and weighed 5.5 tons (5,500 kg) and was a member of a group called titanosaurs that included Earth’s largest-ever land animals. Like many titanosaurs, Mansourasaurus boasted bony plates called osteoderms embedded in its skin.

Mansourasaurus, which lived near the shore of the ancient ocean that preceded the Mediterranean Sea, is one of the very few dinosaurs known from the last 15 million years of the Mesozoic Era, or age of dinosaurs, on mainland Africa. Madagascar had a separate geologic history.

Its remains, found at the Dakhla Oasis in central Egypt, are the most complete of any mainland African land vertebrate during an even larger time span, the roughly 30 million years before the dinosaur mass extinction 66 million years ago, said paleontologist Hesham Sallam of Egypt’s Mansoura University, who led the study published in the journal Nature Ecology and Evolution.

The scientists recovered parts of its skull, lower jaw, neck and back vertebrae, ribs, shoulder and forelimb, back foot and osteoderms. A lot of Africa is covered in grasslands, savannas and rain forests that obscure underlying rock where fossils may be found, said postdoctoral researcher Eric Gorscak of the Field Museum in Chicago, who was formerly at Ohio University.

While as massive as a bull African elephant, Mansourasaurus was modestly sized next to titanosaur cousins such as South America’s Argentinosaurus, Dreadnoughtus and Patagotitan and Africa’s Paralititan, some exceeding 100 feet (30 meters) long.

“Mansourasaurus, though a big animal by today’s standards, was a pipsqueak compared to some other titanosaurs,” said paleontologist Matt Lamanna of the Carnegie Museum of Natural History in Pittsburgh.

The researchers determined Mansourasaurus was more closely related to European and Asian titanosaurs than to those from elsewhere in Africa and other Southern Hemisphere land masses including South America formerly joined in a super-continent called Gondwana.

“This, in turn, demonstrates for the first time that at least some dinosaurs could move between North Africa and southern Europe at the end of the Mesozoic, and runs counter to long-standing hypotheses that have argued that Africa’s dinosaur faunas were isolated from others during this time,” Lamanna said.

By: Reuters

Fossil Bone Tissues Shed Light on Australia’s Polar Dinosaurs

Thursday, January 25, 2018

The fossil bone tissue reveals new information about how the Australian “hypsilophodontid” dinosaurs lived.| Image: Peter Trusler

Dinosaurs that lived in what is now known as Victoria more than 120 million years ago would have dealt with prolonged periods of darkness and below freezing temperatures, a new study reveals.

The study, published in the Scientific Reports journal, examines the bone tissue microstructure of plant-eating “hypsilophodontid” dinosaurs known to have lived in the Antarctic Circle - now Victoria, Australia. 

“These little dinosaurs would have dealt with prolonged periods of darkness and mean annual temperatures near freezing, and certainly below freezing in the winter,” says one of the study authors, Dr Patricia Vickers-Rich, a professor of paleobiology at Swinburne.

In studying fossils from seventeen individuals, the International research team from Swinburne University of Technology, Oklahoma State University, Museums Victoria, and Monash University produced the first life history reconstructions for these small Australian polar dinosaurs.


Examining bone microstructure
An examination of the bone microstructure, or histology, of the hypsilophodontid fossils revealed many characteristics of their growth.

Rings in the bone, similar in appearance to tree rings, helped determine individual age. Bone fibre orientation, blood vessel density, and the amount of bone between growth rings, was used to determine annual growth rates.

Bone histology revealed that, in general, growth was most rapid during the first three years of life, and the dinosaurs were fully grown – the size of a medium wallaby or average turkey - in five to seven years.


Uncovering Australia’s past

The hypsilophodontid samples were recovered from two Australian localities along the south Victorian coast stretching from west of Cape Otway to Inverloch, geologically separated by about 12 million years.

However, the trend of rapid growth for three years followed by adult body size between five and seven years, was conserved across the two samples.

“Given the geologic time involved, we may be looking at several polar dinosaur species in this sample, but their growth trajectories are so similar that we cannot differentiate them from one another based on their growth patterns and rates alone,” says Holly Woodward (Oklahoma State University).

“Instead, our life history assessment demonstrates to us that this generalised growth trajectory was a successful lifestyle for surviving in a region experiencing unique conditions.”


Histologic examinations

The tibia (shin-bone) of one hypsilophodontid individual in the sample had clearly suffered from a pathologic condition known as osteomyelitis or bone infection.

Microscopic examination revealed the cause of this pathology was most likely a broken bone, which then became infected. Counting the growth rings preserved in this tibia prior to the formation of the pathologic bone, the team was able to place the timing of the injury as having occurred when this individual was approximately four years old. 

The team was also able to tease out how long this little dinosaur lived and how it dealt with the injury: histologic examination of the unaffected femur (thigh bone) of this individual shows that it survived with the injury and pathology for three more years.

”Further investigations of this unique sample will continue to shed light on how these little dinosaurs thrived in high latitudes and under the most stressful of environments during a time when dinosaurs flourished on planet Earth,” Dr Vickers-Rich says.

Source: www.swinburne.edu.au

Caihong juji: This Chinese 'Rainbow Dinosaur' had Iridescent Feathers like Hummingbirds

Wednesday, January 17, 2018

An illustration of a reconstruction of the iridescent dinosaur which had rainbow feathers, named Caihong juji, unearthed in China, is shown in this October 31, 2016 photo released on January 15, 2018. Courtesy Velizar Simeonovski/The Field Museum for the University of Texas at Austin

Newly discovered Caihong juji, a winged dinosaur that roamed what is now China around 161 million years ago, was likely bursting with color—a shock of blue and green around its face, and streaks of orange highlighting its wings and tail. The duck-sized theropod has already been christened with the Mandarin word for “rainbow.”

Microscopic structures in the exquisitely preserved, nearly complete fossil unearthed in Hebei Province indicated that it boasted iridescent feathers, particularly on its head, neck and chest, with colors that shimmered and shifted in the light, like those of hummingbirds.

The discovery “suggests a more colorful Jurassic World than we previously imagined,” said evolutionary biologist Chad Eliason of the Field Museum in Chicago, one of the researchers in the study published in the journal Nature Communications.

Photos and drawings of the incredibly detailed C. juji fossil. Credit: Yu et al., 2018

Using powerful microscopes, the scientists detected within the feathers the remnants of organelles called melanosomes responsible for pigmentation. Their shape determines the color. Caihong’s feathers had pancake-shaped melanosomes similar to those of hummingbirds with iridescent feathers.

Much of its body had dark feathers, but ribbon-like iridescent feathers covered its head and neck. While it possessed many bird-like characteristics, the researchers doubted it could actually get airborne. Its plumage could have attracted mates while also providing insulation.

By examining the fossilized feathers under a microscope, researchers detected structures that hint at possible colors. COURTESY YU ET AL., 2018

Caihong was a two-legged predator with a Velociraptor-like skull and sharp teeth, probably hunting small mammals and lizards. It had crests above its eyes that looked like bony eyebrows. 

Many dinosaurs possessed feathers. Birds evolved from small feathered dinosaurs near the end of the Jurassic Period. Caihong had fuzzy feathers and pennaceous ones, those that look like writing quills. It is the earliest-known creature with asymmetrical feathers, a trait used by birds to steer when flying. Caihong’s were on its tail, suggesting tail feathers, not arm feathers, were first utilized for aerodynamic locomotion.

“It is extremely similar to some early birds such as Archaeopteryx,” said paleontologist Xing Xu of the Chinese Academy of Sciences, referring to the earliest-known bird, which lived 150 million years ago. “Its forelimbs were configured like wings. To be honest, I am not sure what function the feathers have, and I don’t think that you can completely exclude the possibility that the feathers helped the animal to get in the air.”

The shapes of melanosomes can help researchers infer coloration. COURTESY YU ET AL. 2018

Asked what someone might say upon seeing Caihong, University of Texas paleontologist Julia Clarke said, “‘Wow!’ And if they are anything like me, they might want one as a pet. Not suitable for children.”

The dinosaur’s full scientific name, Caihong juji, means “rainbow with a big crest.”

Source: www.reuters.com

‘SIBERIAN TITAN’: Russian Scientists Discover New Dinosaur Species (PHOTOS)

Monday, January 15, 2018

© tsu.ru

Russian scientists have described a new dinosaur species that roamed Siberia 120 million years ago, naming it the Siberian Titan. The giant with its long neck & tail is only the second of its type discovered on Russia’s territory.

Paleontologists from the Tomsk State University together with their counterparts from the University of St. Petersburg have identified a previously unknown type of giant dinosaur after uncovering its fossils in a cliff in the Kemerovo region. Fragments of teeth, vertebra and sacrum helped researchers towards realizing that their findings belonged to a new dinosaur species.

© tsu.ru

The creature had a long neck and a powerful tail, could reach up to 12 meters in length and weigh nearly ten tons. Despite its remarkable size, the scientists noted the beast wasn’t the largest in the group of giant plant-eating sauropods. Yet the creature was formally named as “Sibirotitan astrosacralis” due to the area it inhabited and ribs arranged in a ‘star’ shape, according to press releases by the two universities. 

© tsu.ru

First recovered in 2008, the remains required some effort to be extracted from sandstone in a cliff near the village of Shestakovo. Equipped with climbing gear, the researchers had to carefully dig out the bones from the rock at a height of four meters.

The Siberian Titan is the second sauropod unearthed and described in Russia after the discovery of Tengrisaurus in 2017.

© tsu.ru

Source: www.rt.com

Diluvicursor pickeringi: Turkey-sized dinosaur discovered in Australia

Saturday, January 13, 2018

Artist's impression of two Diluvicursor pickeringi foraging on the bank of a high-energy river within the Australian-Antarctic rift valley. Credit: Peter Trusler.

The partial skeleton of a new species of turkey-sized herbivorous dinosaur has been discovered in 113 million year old rocks in southeastern Australia. As reported in open access journal PeerJ, the fossilized tail and foot bones give new insight into the diversity of the small, bipedal herbivorous dinosaurs called ornithopods that roamed the great rift valley that once existed between Australia and Antarctica. The new dinosaur has been named Diluvicursor pickeringi, which means Pickering's Flood-Running dinosaur.

Lower Cretaceous rocks of the deep sedimentary basins that formed within the Australian-Antarctic rift are now exposed as wave-cut rock platforms and sea-cliffs along the south coast of Victoria. The skeleton of Diluvicursor pickeringi was discovered in 2005 by volunteer prospector George Caspar, eroding from such a rock platform at a locality called Eric the Red West, near Cape Otway.

"Diluvicursor shows for the first time that there were at least two distinct body-types among closely related ornithopods in this part of Australia," Dr Matt Herne, lead author of the new study said.

"One was lightly built with an extraordinarily long tail, while the other, Diluvicursor, was more solidly built, with a far shorter tail. Our preliminary reconstruction of the tail musculature of Diluvicursor suggests this dinosaur was a good runner, with powerful leg retracting muscles," Dr Herne said.

"Understanding the ecology of these dinosaurs—what they ate, how they moved, where they roamed—based on the interplay between anatomy and the environment presents exciting challenges for future research."

The late David Pickering on the coastal shore-platform near the fossil vertebrate locality of Eric the Red West, where Diluvicursor pickeringi was discovered. Credit: Matt Herne

The species name honors the late David Pickering, who was Museums Victoria's Collection Manager, Vertebrate Palaeontology. David contributed significantly to Australian paleontology in the lab and field, and tirelessly assisted countless students of paleontology and researchers to achieve their goals. Sadly, David passed away just over a year ago on Christmas Eve 2016.

The site of Eric the Red West has additional importance as it helps build a picture the ancient rift valley ecosystem. Fossil vertebrate remains at this site were buried in deep scours at the base of a powerful river, along with flood-transported tree stumps, logs and branches.

"The carcass of the Diluvicursor pickeringi holotype appears to have become entangled in a log-jam at the bottom of this river," explained Dr Herne. "The sizes of some of the logs in the deposit and the abundance of wood suggest the river traversed a well-forested floodplain. The logs preserved at the site are likely to represent conifer forests of trees within families still seen in Australia today."

"Much of the fossil vertebrate material from Eric the Red West has yet to be described, so further  and other exciting animals from this site are now anticipated."

The holotype partial skeleton of Diluvicursor pickeringi after it was prepared from several blocks of sandstone by Lesley Kool of Monash University The fossil preserves most of the tail along with the right ankle and foot. Credit: Steve Poropat and Museums Victoria (CC-BY).

Source: phys.org

Research finds lizard inside fossilised dinosaur to be a new species

Sunday, January 7, 2018

The fossil of Compsognathus longipes dinosaur found in Germany.

The dinosaur is estimated to have lived around 150 to 145 million years ago.

A new research report has concluded that a lizard whose fossils were found inside a dinosaur skeleton in 1859 is indeed a new species, putting to rest a puzzle that has baffled scientists for more than 150 years.

Prior to this finding, the gekho-like creature, which was found inside the gut of a fossilised carnivorous dinosaur Compsognathus longipeswas thought to be an extinct lizard in Germany (Bavarisaurus macrodactylus).

The author of the new report is Dr. Jack L. Conrad of the American Museum of Natural History, whose findings have been published posthumously in the Zoological Journal of the Linnean Society last month.

The report points to the unique shape of the lizard's skull stitchings and skull bones. Dr. Conrad named the lizard Schoenesmahl dyspepsia, which roughly means ‘beautiful meal that is difficult to digest’.

The dinosaur skeleton was discovered in Bavaria, Germany, by Dr. Joseph Oberndorfer in 1859. The dinosaur is estimated to have lived in the Late Jurassic era—around 150 to 145 million years ago.

This is not the first time a fossil has been found within a fossil. In 2016, there was a report in Palaeobiodiversity and Palaeoenvironments about an insect inside a lizard inside a snake fossil. There have been several reports of fish inside fish fossils. These findings help us know more about their dietary preferences.

Source: thehindu.com

Serikornis Sungei Fossil Gives a Glimpse Into the Evolution of Feathers

Friday, January 5, 2018

Silky Serikornis sungei (Credit: naturalsciences.be)

Exquisitely well-preserved feathered dinosaurs from the Late Jurassic and Early Cretaceous of north-eastern China have considerably helped paleontologists to better understand how birds evolved from dinosaurs. It has been previously postulated that the emergence of feathers was driven by their aerodynamic properties but a new species, named Serikornis sungei “the silk bird”, provides new clues about how dinosaurs feathers evolved.

The little pheasant-sized dinosaur, which bears four wings (that is, two forewings and two hindwings) is mainly covered with simple feathers similar to the wispy bundles found in other dinosaurs like Sinornithosaurus. The first four-winged dinosaur, as known as Microraptor, was reported from the Tiaojishan Formation in Liaoning Province in 2000.

This Middle-Late Jurassic Formation has already provided other four-winged species such as Aurornis and Anchiornis, another basal dinosaur close to the transition between dinosaurs and birds. The plumage of Serikornis is well-preserved and the limbs bear short, slender, symmetrical, and poorly differentiated feathers similar to those of Anchiornis. In other words, the limb feathers attached to the arms and the legs of Serikornis are totally different from the flight feathers of modern birds.

Details on the two major plumage traits of Serikornis attesting that it was a ground-dwelling dinosaur: (i) the plumage of the forewing is primitive and not composed of long pennaceous flight feathers covered by short coverts. (ii) Saw under electronic microscope, the macrostructure of its feathers are devoid of barbules, a trait to allow the feather to resist air pressure during the wing beat.

Serikornis wasn’t a flier and its anatomy coupled to the macrostructure of the feathers indicate a terrestrial mode of life. Although the hindlimbs bear feathers, a feature often associated with the evolution of flight, they are not suited to sustain a flight. So the presence of leg feathers on a more archaic and grounded dinosaur imply that long leg feathers evolved in a terrestrial context. The structure of the pennaceous feathers also goes in that direction because of barbules, a structure that hook barbs together and which is essential to resist air pressure during the wing beat, are absent in Serikornis. This absence is corroborated by optical and electronic microscopy.

What does the plumage of Serikornis serve? It is postulated that the feathering of this little dinosaur may have primitively been used as a thermoregulatory system or as a social display even if it could not be ruled out that Serikornis was able to scramble up tree trunks with its sharp and recurved claws and parachute to the ground, using its plumage to slow down its descent.

The next step of the research will bring new information about how the terrestrial context has driven the emergence of flight among basalmost Jurassic paravians and how this emergence has played a major role on the diversification of ecological niches necessary to develop a modern-like type of flight.

These findings are described in the article entitled A new Jurassic theropod from China documents a transitional step in the macrostructure of feathers, published in the journal The Science of Nature. This work was led by Ulysse Lefèvre at the Royal Belgian Institute of Natural Sciences.

Source: sciencetrends.com

Top Fossil Discoveries of 2017

Sunday, January 14, 2018

 Some of the best fossils of 2017. Composite: WILLIAM GRAF, University of Wisconsin – Madison/Erikkson et al 2017/Lukas Panzarin/Andrea Cau/Royal Tyrrell Museum of Palaeontology

The Lost Worlds Revisited team has been reflecting on a bumper twelve months of palaeontological discoveries. Overwhelmed with choice, we also asked on Twitter for other people’s favourite fossil finds of 2017. So here is a combination of those fossiliferous suggestions, alongside some of our personal favourites. Enjoy!

First life on earth

Some of the smallest fossil finds of 2017 were among the most controversial. In March, Matthew Dodd and colleagues described tiny tubes and filamentscomposed of iron oxide in rocks from Quebec, Canada dated between 3.77bn and 4.28bn years old. They interpreted them as the remains of bacteria living around hydrothermal vents, pushing the earliest evidence of biological activity to more than 3.77bn years ago, and conceivably even a staggering 500m years earlier. In September, Takayuki Tashiro and colleagues analysed graphite particles from rocks 3.95bn years old from northern Labrador, Canada. They concluded from isotope ratios that the carbon was biologically produced, although this interpretation was not shared by all researchers.

Finally, in research published mid-December, Bill Schopf and colleagues used the carbon isotope composition of microfossils in the 3.46bn year old Apex Chert, from Western Australia, to confirm their previously-disputed biological origins and even work out which groups of microbes were represented. Two species were primitive bacterial photosynthesizers, one was a methane-producing Archaean microbe, and two others were bacterial methane consumers. This impressive study shows that methane-cycling microbial communities were already established by 3.5bn years ago.


Halszkaraptorthe bird-like bombshell

2017 was a great year for paleontologists, and it was hard to keep up with all the fossil splendor coming at me from various angles. However, one that stood out is the recently described fossil of a theropod dinosaur - studied non-invasively with high-tech 3D scanning - that shows amazing bird-like features. 

The theory that birds descended from dinosaurs is now commonly accepted amongst vertebrate palaeontologist. The discovery of exquisitely well preserved fossils, such as those from Liaoning province in China, has shown us that many features we once reserved for birds, were actually widespread amongst theropod dinosaurs (the group of dinosaurs that ultimately gave rise to birds), including those that were not on the lineage towards birds.

But no one could have predicted Halszkaraptor escuillieia new species of non-avian theropod dinosaur from Mongolia (Cau et al., 2017). Its long neck, constituting 50% of the total snout-to-tail length and the longest for any Mesozoic theropod dinosaur, is reminiscent of that seen in some birds, particularly swans. Halszkaraptor forms a new group of dromaeosaurids, the Halszkaraptorinae, and its unusual morphology suggests a semi-aquatic lifestyle. Its flattened wing bones are also seen in penguins and other aquatic birds, and the large number of teeth indicate that it was a predator. Moreover, Halszkaraptor appears to be the first non-avian dinosaur who was able to move both on land and in the water. As the authors of the research state in their last paragraph, the peculiar looks of Halszkaraptor shows us how much of the diversity of dinosaurs remains to be undiscovered.


Borealopelta markmitchelli

This is a new armoured dinosaur (a relative of the famous ankylosaurus) whose discovery was first reported in these pages back in 2013 because of the exceptional circumstances around its discovery in northern Alberta. Spotted by an excavator crew as a dot on a hillside, this remarkable creature is a real rarity, a land living animal that had floated many miles out to sea before it sank, intact, was buried, and eventually recovery millions of years later. The rock in which it was entombed was exceptionally tough and the bones fragile, so it took museum preparator Mark Mitchell years to prepare. He was rewarded when the animal was finally named as a new species.

However, the fossil itself turned out to be more remarkable still than the circumstances around its death and fossilisation. Borealopelta is one of the best preserved dinosaurs ever discovered: not only is the main skeleton very nearly complete, but the huge number of bony spikes and plates that make up its armour are also preserved. Better yet, they retain their original positions, so it is possible to see how they line up and change along the body. Even better still, much of the armour retains the horny sheathes that covered it. The skin of the animal is brilliantly preserved and in such fidelity that work has already been published on the colours and patterns of Borealopelta, and the likely use of its huge shoulder spines in displays.


Shringasaurus, the ‘horned lizard of India’

Following the biggest mass extinction in Earth’s geological history, at the end of the Permian, evolution in the Triassic period was like a teenager who has just left home for the first time. Finding itself in a new world free of constraints, it became wildly experimental. Many of these wacky, chimeric combinations have never been repeated (similar to most people’s experience of the 1980s). Evolution likes to try everything at least once. 

In 2017, Shringasaurus indicus (‘horned lizard of India’) evidenced the singular nature of these Triassic lifeforms. This newly-found archosauromorph waddled on four sprawled legs across what is now India, around 240m years ago. It had two forward pointing horns on its head, at the end of a long neck and body. With a humped, powerful shoulder at the front and sinuous back-end with long tail, it was like the love-child of a rhino and a komodo dragon. At around three-and-a-half metres long, this chunky, odd-ball herbivore would have been analogous to the large bovid species of the modern world (cows). It has been suggested that the horns of Shringasaurus were used for sexual selection, as in cattle. Having found the partial remains of several Shringasaurus individuals of different ages and genders, researchers were able to say a lot about how this animal grew, and that the horns were sexually dimorphic – meaning that only male animals possessed them.

Triassic animals like Shringasaurus are vital to helping us understand the bigger evolutionary picture. They were part of the first ecosystems established after the end-Permian mass-extinction, giving us information about how life on earth recovers from disaster. They were also the predecessors of the major radiations of crocodiles, turtles, dinosaurs, and multiple now-extinct reptilian lineages that would succeed them. They were also fantastically weird; which is why at least one of them deserves to be in the top fossil discoveries of the year.


The giant fossil Bobbit worm

If you have read Frank Herbert’s science-fiction novel Dune, you are aware of sandworms: the colossal worm-like creatures that inhabit the desert planet Arrakis. Thankfully, us earthlings do not have to worry about being swallowed by giant worms, but jaw fossils found in the Devonian of Ontaria, Canada, show that giant worms did once exist on earth.

Websteroprion armstrongi (partially named after death metal bass player Alex Webster) is a new species of giant bristle worm (polychaete) described based on these partial jaw fossils. Despite being long and squishy, bristle worms have a decent fossil record. They have been present since the Paleozoic (541-251 million years ago) and extinct forms show a diversity of body plans. The specimens were collected back in 1994, by Derek K Armstrong of the Ontario Geological Survey at a remote location in Ontario, and had been stored at the Royal Ontario Museum. 

Of this new fossil bristle worm, only the jaws (the only hard part in these animals) are preserved. The fossil jaws may have measured over 1 cm in length. Granted, this does not sound particularly awe-inspiring, but in the world of worms, Websteroprion’s jaws are truly colossal, as fossil polychaete jaws generally measure 0.1-2mm. By extrapolating from the size of the jaw fossils, the authors of the study estimate that Websteroprion armstrongi could have been 1-2 meters in length, comparable to living ‘giant eunicid’ species, colloquially referred to as ‘Bobbit worms’. The jaw fragments indicate that the animal was adult, and as some polychaetes continue to grow as adults, W. armstrongi could have attained larger lengths. W. armstrongi has the largest known jaws from the worm fossil record, and demonstrates that gigantism, an ecologically important trait, was already present in worms by 400 million years ago. Furthermore, they show the importance of existing museum collections, as they may contain overlooked gems.


Antarcticeras nordenskjoeldi


2017 was a bumper year for palaeontological discoveries and I don’t think a week went by when the Lost Worlds Revisited team didn’t have plenty of options to write about. However, in addition to the glitzy and glamorous headline-making discoveries, 2017 was also a good year for the more humble additions to species lists, taxonomic clean-ups and the palaeontological quiet work that happens away from the exceptionally preserved fossils and dino discoveries. This time of year I love looking through Wikipedia’s summaries of the year in palaeontology for the discoveries big and small and I must confess that my top fossil this year one I didn’t hear about when it was published back in March this year.

My pick for this year is a new species of Eocene cephalopod (the group containing octopuses, cuttlefish, nautiloids and ammonoids) from Antarctica, Antarcticeras nordenskjoeldi. The fossils themselves aren’t especially eye-catching and there isn’t a beautiful artistic reconstruction of the species accompanying the paper, however, it’s the interpretation of the fossils by colleagues in Sweden and Argentina that is noteworthy (Doguzhaeva et al. 2017). From details of the shell structure and position of the siphuncle (the tube that exchanges gases and fluids through shell chambers), A.nordenskjoeldi has been interpreted as a new species, in a new family, in a new order and amazingly the sole known member in a new cephalopod subclass, the Paracoleoidea.

This is a potentially huge new finding, adding a major new group of cephalopods alongside the four major and stable divisions, and the authors suggest that fossils of A.nordenskjoeldi represent a third way that soft bodied cephalopods evolved an internal shell in parallel with cuttlefish and ram’s horn squid. Fortunately, the paper itself is open access so you can take a look yourself, but the implication here, to borrow Internet parlance, is HUGE if true. It’s a bold interpretation, which is sometimes needed in science and time will tell if the Paracoleoidea will be accepted or rejected. So far the findings don’t seem to have created that many ripples in cephalopod palaeontology. Were this an equivalent suggestion in mammals or dinosaurs the paper would have garnered a huge amount of attention (as we saw with the ‘lower level’ saurischian/ornithischian research this year) but as it’s a relatively obscure group in the humble cephalopods this research risks fading into obscurity rather than cause a re-evaluation of cephalopod evolution.




Brown CM, Henderson DM, Vinther J, Fletcher I, Sistiaga A, Herrera J, Summons R. 2017. An exceptionally preserved three-dimensional, armored dinosaur reveals insights into coloration and Cretaceous predator-prey dynamics. Current Biology 27(16):2514-2521.

Cau A, Beyrand V, Voeten DFAE, Fernandez V, Tafforeau P, Stein K, Barsbold R, Tsogtbaatar K, Currie PJ, Godefroit P. 2017. Synchrotron scanning reveals amphibious ecomorphology in a new clade of bird-like dinosaur. Nature 552: 395–399.

Doguzhaeva LA, Bengtson S, Reguero MA, Mörs T (2017) An Eocene orthocone from Antarctica shows convergent evolution of internally shelled cephalopods.PLoS ONE 12(3).

Eriksson, M., et al., 2017. Earth’s oldest ‘Bobbit worm’ – gigantism in a Devonian eunicidan polychaete. Scientific Reports 7:43061.

Sengupta S, Ezcurra MD, Bandyopadhyay S. 2017. A new horned and long-necked herbivorous stem-archosaur from the Middle Triassic of India. Scientific Reports. 7: 8366


Source: www.theguardian.com

Chicken-sized Dinosaurs Added to Raptor Family Tree

Sunday, December 31, 2017

Halszkaraptor, a new and strange raptor dinosaur from Mongolia.

Two new species of raptor dinosaurs were discovered last week from a site in Mongolia.

The first of these, “Halszkaraptor”, was described in the journal “Nature” and has been described in the media as a raptor dinosaur with similarities to swans, geese, and penguins. While that description is illustrative, the details of the features of this animal deserve closer examination.

About the size of a chicken, “Halszkaraptor” is not a large dinosaur. It had a small head and a long slender neck. It did not have beak. Instead, its mouth bristled with over 100 small pointed teeth. Its snout also appears to have been sensitive, like that of a crocodile, possibly to detect prey underwater. It would have had feathers, but is not thought to have flown. Instead, its short forelimbs, including a very long third finger, look a lot like the “paddles” of some fossil swimming reptiles, so it may have used its arms to swim like a penguin today. However, its feet looked much more like those of a “Velociraptor”, including a wickedly-curved enlarged claw on each foot.

These features show a dinosaur with unique evolutionary adaptations not seen in non-bird dinosaurs until now. It is a very odd and exciting discovery.

Later in the week, a close relative of “Halszkaraptor” was described in the journal “American Museum Novitates.” Called “Almas”, a reference to the Mongolian yeti, this dinosaur is more closely related to dinosaurs like “Troodon” that appear as the Philip J. Currie Dinosaur Museum’s logo. While similar to its close relatives, it was found to be a distinct species based on several features, including a short skull and fewer teeth.

Interestingly, “Almas” is also associated with eggshell fragments. While similar in size to “Halszkaraptor”, “Almas” is too large to be a hatchling. It may have been protecting or brooding the eggs.

Small dinosaurs are a rare part of the fossil record, so adding these two dinosaurs from Mongolia in the same week is quite exceptional. The rate of dinosaur discovery in the world is not slowing down, and palaeontologists are always continuing to hunt for the next find.