All about dinosaurs, fossils and prehistoric animals by Everything Dinosaur team members.
//April
21 04, 2017

New Species of Hyaenodont from Egypt Described

By | April 21st, 2017|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Masrasector nananubis – From the Late Eocene of Egypt

If people are asked to name a meat-eating mammal, you can expect to get answers such as tiger, bear or lion.  Those of us with more of a domestic outlook on life might mention cats and dogs, but for a significant portion of the Cenozoic, sometimes referred to as the “Age of Mammals”, the Carnivora, the Order to which bears, cats and dogs belong, did not get a look in.  Prior to the evolution of many types of recognisable carnivorous mammal alive today, other types of mammals filled the role of hypercarnivores*.

One such group was the Hyaenodonta.  A diverse clade of carnivorous mammals that filled a variety of roles in terrestrial ecosystems in both the New and the Old World.  Writing in the on-line academic journal PLOS One, scientists from Ohio University and the University of Southern California have published details of a new species of Yorkshire terrier-sized hyaenodont, the beautifully preserved skull and jaws are helping palaeontologists to understand more about the evolution and phylogeny of this extinct group, a group that has no close relatives alive today.

The Skull and Jaws of a Newly Identified Species of Hyaenodont

Skull and jaws of Masrasector nananubis.

Computer generated image showing the skull and jaws of Masrasector nananubis (right lateral view).

Picture Credit: PLOS One

Masrasector nananubis – Named after a God of Ancient Egypt

The Late Eocene deposits of the Fayum Depression (Egypt), have provided scientists with a substantial number of mammal fossils, including a number of hyaenodonts, the latest to be added to this list is Masrasector nananubis.  It has been classified as member of the Hyaenodontidae, specifically part of the Teratodontine clade, a poorly known group which are distinguished from other hyaenodonts by subtle differences in the shape of their skulls, jaws and teeth.  Masrasector translates as “the Egyptian slicer”, a reference to the large molars (carnassials).  The species or trivial name honours Anubis, the jackal-faced Egyptian god of mummification.  The premolars and molars of Masrasector have larger grinding surfaces when compared to other hyaenodonts.  The researchers have speculated that Masrasector nananubis may have supplemented its diet of small mammals, amphibians, reptiles and insects by feeding on fruit and nuts.  This suggests that, like other members of the Teratodontinae clade, it may not have relied on meat consumption as much as other hyaenodonts that were hypercarnivorous.  It has been suggested that M. nananubis may have been mesocarnivorous*.

Views of the Skull of Masrasector nananubis

Cranium material of Masrasector.

Views of the skull of Masrasector (Hyaenodont).

Picture Credit: PLOS One

It may be true that hyaenodont fossils are known from Africa, North America, Asia and Europe and that the genus Hyaenodon survived for around twenty-six million years, the longest temporal spam known for a fossil mammal, but the discovery of these Masrasector fossils is still very significant.  The fossils comprise largely complete skulls, jaws, and parts of the skeleton, making them one of the most complete known African hyaenodonts from the Paleogene found to date.  Previously, researchers only had isolated bones and teeth fragments to work with, frustrating palaeontologists as they attempt to piece together the family tree representing the Hyaenodontidae.

The fossils come from a dig site (locality 41) in the Fayum Depression, the well-consolidated clays have been dated to the Late Priabonian of the Eocene (approximately 34 million years ago).  The Masrasector material represents some of the oldest fossils known for this type of hyaenodont.

Commenting on the importance of the fossils, corresponding author for the study, Matthew R. Borths (Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University), stated:

“These fossils might be the oldest and most complete ever discovered, but there is still much that remains to be discovered as the fossils of other members of this group are fragmentary.  Masrasector can be used as a cornerstone of character development for exploring the evolution and diversity of other hyaenodontids.”

 

An Illustration of the Giant Hyaenodont (H. gigas)

Hyaenodon gigas scale drawing.

A scale drawing of the giant Hyaenodon gigas.

Picture Credit: Everything Dinosaur

Matthew went onto add:

“Hyaenodonts were the top predators in Africa after the extinction of the dinosaurs.  This new species is associated with a dozen specimens, including skulls and arm bones, which means we can explore what it ate, how it moved, and consider why these carnivorous mammals died off as the relatives of dogs, cats, and hyenas moved into Africa.”

Hypercarnivore* an animal which has at least 70% of its diet made up of meat.

Mesocarnivore* an animal which has around 50% to 70% of its diet made up of meat.

The scientific paper: “Craniodental and Humeral Morphology of a New Species of Masrasector (Teratodontinae, Hyaenodonta, Placentalia) from the Late Eocene of Egypt and Locomotor Diversity in Hyaenodonts” by Matthew R. Borths and Erik R Seiffert published in PLOS One.

20 04, 2017

SpinoDude Reviews Polacanthus

By | April 20th, 2017|Dinosaur Fans, Everything Dinosaur videos, Main Page, Photos of Everything Dinosaur Products|0 Comments

Papo Polacanthus Video Review

SpinoDude has produced a very informative review of the new for 2017 Papo Polacanthus dinosaur model.  Papo’s promotional images of this plant-eating dinosaur did not do it justice and SpinoDude addresses this by showcasing some of the exquisite details that can be found on this replica, one of six dinosaur figures (including two repaints), to be added to Papo’s “Les Dinosaures” range this year.

The Video Review of Polacanthus

Video Credit: SpinoDude Reviews

In this short, seven-minute video review, SpinoDude shows the model in close-up and highlights some of the features of this replica, such as the carefully painted eye and the subtle detailing around and inside the mouth.  One of the great things about SpinoDude dinosaur model reviews is that the narrator starts by providing some scientific information about the dinosaur in question.  For example, the sacral shield is commented upon and the video contains images of the sacral shield and pelvis elements collected from the Lower Cretaceous of Barnes High, (Isle of Wight), what are in fact, the pelvis fossils of the Polacanthus holotype (NHMUK R175).

The SpinoDude YouTube channel has nearly 1,000 subscribers and the channel contains dozens of skilfully made prehistoric animal model reviews.

To see the channel and to subscribe to SpinoDude: SpinoDude Reviews YouTube Channel

 An Eagerly Anticipated Dinosaur Model

The narrator describes the Papo Polacanthus as one of the most eagerly anticipated figures to be introduced by Papo this year.  The spectacular Acrocanthosaurus and Papo Ceratosaurus may have stolen a lot of the limelight, but discerning collectors will appreciate the quality of this armoured dinosaur.  On our travels, we have had the pleasure of studying North American Cretaceous polacanthids as well as writing about the discovery of “the Horsham specimen” from Rudgwick, Surrey.  The disarticulated fossil material recovered from a brickworks quarry, representing strata deposited in the Early Cretaceous (Barremian faunal stage), has led to the establishment of a new member of the armoured dinosaurs, within the Polacanthinae clade but not that closely related to Polacanthus foxii.  This new dinosaur has been named Horshamosaurus. (H. rudgwickensis).

Everything Dinosaur’s Picture of the Papo Polacanthus

Papo Polacanthus replica.

Papo Polacanthus dinosaur model.

Picture Credit: Everything Dinosaur

To view the range of Papo prehistoric animal figures available from Everything Dinosaur: Papo Dinosaur and Prehistoric Animal Models

The Papo Polacanthus Dinosaur Model

Papo Polacanthus model.

Papo Polacanthus dinosaur model.

Picture Credit: Everything Dinosaur

Dr William Blows (the scientist responsible for describing and naming Horshamosaurus), recently published an excellent book which comprehensively reviewed the research undertaken into British polacanthids and their North American cousins.

“British Polacanthid Dinosaurs” by William T. Blows

"British polacanthid Dinosaurs".

Written by William T. Blows.

Picture Credit: Siri Scientific Press

For further details: Visit the Website of Siri Scientific Press

Our thanks to SpinoDude for his super Papo Polacanthus video review.

19 04, 2017

Prehistoric Seagull from the Outback

By | April 19th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Nanantius eos and the Eromanga Sea

The Queensland town of Richmond may be several hundred miles from the Coral Sea that laps against the coast of north-eastern Australia, but back in the Cretaceous this part of world, famous for its droughts and arid outback, was covered for millions of years by a shallow, tropical sea (the Eromanga Sea), that teemed with prehistoric life.  Thanks to the efforts of volunteers and the dedicated researchers at Richmond’s Kronosaurus Korner a new ancient resident has been identified, not a sea monster, or an ancient fish but a primitive bird that probably filled an ecological niche similar to today’s seagulls.

Swooping into view comes Nanantius eos, the name translates as dawn dwarf-enantiornithine*.  Slighter smaller than a Common Tern (Sterna hirundo), perhaps weighing no more than a couple of hundred grammes, the fossils come from marine sandstone deposits that were laid down more than 100 million years ago, (Aptian to Albian faunal stage of the Cretaceous).  Fossils of Nanantius have been found in Winton sandstone exposures around three-hundred miles to the south-west of Richmond, but these consist of only a few isolated bones.  Working at a site just eight miles from the centre of Richmond, Dr Patrick Smith (Curator at the Kronosaurus Korner Fossil Museum), is confident that the number of bird bones found so far indicates that there might be complete skeletons present in the deposit.

Pictures of the Fossil Material Ascribed to Nanantius eos from the Richmond Site

Nanantius fossils from the Richmond site.

Nanantius eos fossils including a partial humerus (left).

Picture Credit: Dr Patrick Smith

Dr Smith commented:

“It’s very, very rare to find dinosaurs out here, there’s only been about a handful known, so finding these dinosaur birds is amazing.  We haven’t had any of these sorts of primitive birds found in Richmond.”

The “Richmond Raptor”

Volunteer Mike D’Arcy found the first evidence of a fossil bird some five years ago.  Ever since his first discovery, he has been busy recruiting volunteers to help him find more fossil evidence.  As, for much of the Early Cretaceous, Richmond was underwater and many miles from land, it is surprising to find evidence of an enantiornithine bird in marine sandstone deposits.  Scientists are unsure how the bird fossils came to be deposited.  Do they represent an accumulation of carcases of birds washed out to sea?  Or perhaps flocks of Nanantius eos (which was probably a capable flyer), may have flown out far to sea in order to feed.  Mike has nick-named the bird the “Richmond Raptor”.  It did have small, sharp teeth in its jaws and claws on its wings but small fish and insects were probably its choice of prey.

Volunteer Mike D’Arcy Working at the Fossil Site

Volunteer Mike D'Arcy working at the dig site.

Mike D’Arcy at the fossil dig site.

Picture Credit: Mike D’Arcy

A spokesperson from Everything Dinosaur commented:

“Local residents can play an important role in helping palaeontologists to collect fossils from sites, that the palaeontologists themselves may not have time to visit and explore themselves.  Thanks to these volunteers, many fossils that would otherwise have been eroded away can be saved, permitting scientists the opportunity to study them.”

Likely member of the Enantiornithine Clade*

Although described as a member of the Enantiornithes clade, a group of abundant, primitive birds of the Cretaceous, it is hoped that the Richmond fossils will be able to confirm this assessment.  Previously, fossils found near the small town of Boulia, (Queensland), included a partial tibiotarsus (ankle and lower leg bone), were attributed to Nanantius.  The shape of this bone was once thought to be diagnostic of the Enantiornithines but more recent Mesozoic bird discoveries have cast doubt on the morphology of the tibiotarsus being suitably diagnostic of a Enantiornithine affinity.  With more fossil bones found, including limb elements (humerus and unguals), palaeontologists may be able to confirm the taxonomic position of N. eos.

Examining a Pedal Ungual (Nanantius eos)

Viewing a claw fossil of Nanantius eos (Cretaceous bird).

Mike D’Arcy examining one of the fossil toe claws.

Picture Credit: Mike D’Arcy

Mike D’Arcy added:

“The first half a dozen pieces I got, we couldn’t really assign what it was and it wasn’t until we got the humerus that we could say it was definitely a bird.”

The fossils are currently on display at the Kronosaurus Korner Fossil Museum. Nanantius is regarded as seabird as fossils have been found in association with marine deposits.  In addition, in 2003, a paper was published in the “Proceedings of the Royal Society – Biology” that described the stomach contents discovered in association with a gravid female Ichthyosaur (Platypterygius longmani).  Amongst the fossilised remains of baby turtles and fish, the scientists discovered limb bones from an Enantiornithine bird, probably from the Nanantius genus.  How the bones came to be in the body cavity of an Ichthyosaur is unknown, perhaps the marine reptile grabbed the bird as it rested on the water, or maybe the Ichthyosaur had fed on a corpse that had been washed out to sea.

18 04, 2017

New Species of Arowana Fish from the Eocene of China

By | April 18th, 2017|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

The Origins of the Dragon Fish (Scleropages)

Scientists from the Institute of Vertebrate Palaeontology and Palaeoanthropology (IVPP) have published details of the discovery of beautifully preserved fish fossils from China that have helped map the origins of one of the most valuable and sought after aquarium fishes in the world.  Scleropages formosus, the Asian Arowana, otherwise known as the Dragon Fish from south-eastern Asia, quite rare in the wild these days, but it is highly regarded amongst freshwater aquarium owners, who can splash out thousands of dollars to acquire particularly colourful specimens.

In a scientific paper published in the journal “Vertebrata PalAsiatica”, Dr Zhang Jiangyong (IVPP) in collaboration with Dr Mark Wilson (University of Alberta), report on the discovery of a new species of osteoglossid fish from the Early Eocene Xiwanpu Formation in Hunan and the Yangxi Formation in Hubei, (China).  The prehistoric fish is remarkable similar to the extant species and it has been named Scleropages sinensis (the name translates as “hard scaled leaves from China”, a reference to the robust tough body scales that characterises these fish).

The Holotype Fossil Material of Scleropages sinensis

The holotype fossil material of S. sinensis.

Holotype of Scleropages sinensis.

Picture Credit: Zhang Jiangyong (IVPP)

The picture above shows the beautifully preserved holotype specimen of S. sinensis.  The fins are labelled (df) = dorsal fin, (cf) = caudal fin, (af) = anal fin, (pf and pec f) = pectoral fins, scale bar 1 centimetre.

This is the first time a nearly complete body fossil of this genus has been described.  Previously, the fossil record only consisted of individual scales, otoliths (calcified structures from the inner ear) and isolated fragmentary bones.  The discovery of Scleropages sinensis dates the divergence of Scleropages from the closely related Osteoglossum to at least as far back as the Early Eocene.  The fish fossils represent a number of different ontogenetic (growth stages). The largest specimens are 17.5 centimetres in length, the smallest under 8 centimetres long.

Fossil Scleropages are known from the Maastrichtian of India, the Maastrichtian/Late Palaeocene of Africa, the Palaeocene of Europe, the Eocene of Sumatra, and the Oligocene of Australia.   All of these earlier records are scales, otoliths and isolated bone fragments. Therefore, these newly described Chinese fossils are the first skeletons of fossil Scleropages ever unearthed in the world.

Views of the Scleropages Fossil Material

Views of Scleropages sinensis fossil material.

Scleropages sinensis fossil material (various views).

Picture Credit: Zhang Jiangyong (IVPP)

Dr Zhang stated:

“This new fish resembles Scleropages in skull bones, caudal skeleton, the shape and position of fins, and reticulate scales.  Therefore, it must belong to the genus.”

The extant species of Scleropages inhabits lakes, swamps and flooded forests as well as slowly meandering rivers. It is a carnivorous fish preying on insects, worms, small amphibians, other fish, small mammals and even birds.  The fish is renowned for its jumping, the researchers propose that Scleropages sinensis may have filled a similar niche in the Eocene ecosystem, but being smaller it probably had a more restricted diet than its extant relative.  Analysis of the fossil material suggests that sexual dimorphism may have existed in S. sinensis.

Comparing the Extinct Species with Living Species

Living species of Scleropages compared to the fossil material.

Comparison between Scleropages sinensis (A) and the living species S. formosus (B), S. leichardti.

Picture Credit: Zhang Jiangyong (IVPP)

17 04, 2017

Prehistoric Times Magazine (Spring 2017) Reviewed

By | April 17th, 2017|Dinosaur Fans, Magazine Reviews, Main Page|1 Comment

A Review of Prehistoric Times Magazine (Spring 2017)

Issue 121 (Spring 2017), of the quarterly magazine “Prehistoric Times” has just arrived and this edition of the popular journal for dinosaur fans and prehistoric animal model enthusiasts has a distinctly “English” feel to it.  Yes, we know the front cover features the amazing artwork of the highly influential Zdeněk Burian, an artist and palaeo illustrator from Czechoslovakia.  This issue contains details of Burian’s commissioned artwork used to help illustrate fiction, one of a series of articles all about the great man written by John Lavas.  However, also included is a feature on London-born, Alice Bolingbroke Woodward, who like Burian, was a pioneer of prehistoric animal illustration, plus look out for Phil Hore’s informative piece on a very enigmatic English Theropod Metriacanthosaurus and the John Sibbick Reader Art.

The Front Cover of Prehistoric Times Issue 121

The front cover of Prehistoric Times magazine (Spring 2017).

The front cover of prehistoric times magazine (Spring 2017).

Picture Credit: Prehistoric Times

The front cover of “Prehistoric Times” features artwork by Zdeněk Burian.

To learn more about “Prehistoric Times” and to subscribe visit the website: Prehistoric Times Magazine

Pliosaurs and the Bristol Museum and Art Gallery

The “English theme” continues with our chum Anthony Beeson’s contribution, a short article highlighting the extensive marine reptile collection associated with the Bristol City Museum.  Anthony discusses the historical significance of the specimens, many of which were originally collected by Mary Anning. He then brings us right up to date with details about a forthcoming marine reptile exhibition that runs from June 17th until early January 2018.

Phil Hore’s second contribution in the magazine, is an article on the bizarre Therapsid Estemmenosuchus, fossils of which come from the Urals, however, Phil’s article begins with comments made by the 19th Century English biologist Thomas Henry Huxley.  It turns out that “Darwin’s Bulldog” got these cow-sized beasties completely wrong.  Look out for some fantastic reader artwork that accompanies this article.

The Sound of the Mesozoic

Robert Telleria continues to put the spotlight on the artwork associated with sound recordings that feature prehistoric animals and on the subject of artwork, check out “What color were dinosaurs?”  Mike Fredericks and Tracy Lee Ford have collaborated on a new dinosaur themed colouring book.  It is reviewed in the “Mesozoic Media” section of the magazine.  Lots of palaeontology news including the discovery of new species of horned dinosaur (Yehuecauhceratops mudei) from Mexico is discussed and check out the wonderful Siats meekerorum illustration by Fabio Pastori.

Yehuecauhceratops mudei – A New Mexican Horned Dinosaur

Yehuecauhceratops Museum Replica

Scientists have constructed a model of the Mexican dinosaur called Yehuecauhceratops.

Picture Credit: Museo del Desierto, Mexico (The Coahuila Desert Museum)

Paying Tribute to Aurora Prehistoric Scenes

Our favourite article in the Spring edition of “Prehistoric Times”, comes from Steve Kelley, who takes readers on a very personal journey as he discusses his love of the Aurora Prehistoric Scenes model series.  What a fantastic collection Steve has been able to amass!  Ironically, this, very informative article does not include any pictures of the “Jungle Swamp” set, which was voted amongst Everything Dinosaur team members as our favourite.  Perhaps it will feature in part two, which is promised for issue 122.

Our Favourite Aurora Prehistoric Scenes Model Set – “The Jungle Swamp”

Aurora Prehistoric Scenes "Jungle Swamp".

Super Aurora Model Kit from childhood.

To subscribe to Prehistoric Times Magazine: Prehistoric Times Magazine

16 04, 2017

Elk Hunter Stumbles Across Elasmosaurid

By | April 16th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|4 Comments

Nakonanectes bradti – Shortest Neck and Youngest Elasmosaur from the Western Interior Seaway

A new genus of elasmosaurid has been added to the list of marine reptiles associated with the Western Interior Seaway.  Named Nakonanectes bradti, this fish-eating monster lived around 70 million-years ago.  A paper detailing the discovery has been published this week in the “Journal of Vertebrate Palaeontology”, Nakonanectes is the youngest elasmosaurid, stratigraphically speaking from the Western Interior Seaway, it also had a very short neck, short at least, when compared to other Late Cretaceous elasmosaurids.

A New Genus of Short-Necked Elasmosaurid from Montana

Nakonanectes illustrated.

An illustration of the newly described elasmosaurid Nakonanectes bradti.

Picture Credit: James Havens

Marine Reptile Discovered by an Elk Hunter

David Bradt in 2010, stumbled across fossils of the marine reptile whilst out hunting for elk in Montana’s Charles M. Russell National Wildlife Refuge.  He noticed a series of articulated bones in a stream bed and thinking that the fossils might represent a dinosaur, David alerted the authorities.  When a field team visited the remote site, they followed the trail of bone fragments uphill and discovered more fossils including the remains of an exquisitely preserved skull.  The Late Cretaceous reptile has been named after the native Nakona people of Montana and the trivial name honours David Bradt.

Field Team Members Working at the Excavation Site

Excavating the elasmosaurid fossil bones.

The location of the elasmosaurid bones.

Picture Credit: Erin Clark/Associated Press

One of the authors of the scientific paper, Pat Druckenmiller (University of Alaska Museum of the North), commented:

“This group [elasmosaurids] is famous for having ridiculously long necks, I mean necks that have as many as seventy-six vertebrae [Albertonectes].  What absolutely shocked us when we dug it out, it only had somewhere around forty vertebrae.”

Nakonanectes bradti Compared to Albertonectes vanderveldei

The Bearpaw Shale Formation has provided scientists with a number of intriguing Cretaceous vertebrate fossils, including Albertonectes (A. vanderveldei).  It is regarded as the longest Plesiosaur known (estimated to have been more than twelve metres long).  Albertonectes also has the longest neck of any Plesiosaur described to date.  The neck is estimated to have been around seven metres long.  The single specimen (holotype) of Albertonectes comes from the Bearpaw Shale Formation, however, these fossils were found in Alberta (near Lethbridge) and as such, come from exposures some two hundred miles north-west of the stream bed in Montana where the remains of Nakonanectes were found.

Nakonanectes bradti is believed to have had around 39-42 neck bones (cervical vertebrate).  In comparison, Albertonectes had a body length twice as long and its neck was two-and-a-half times the length of N. bradti.

Comparing the Size of Nakonanectes to Albertonectes

Elasmosaurid neck size comparison.

Elasmosaurid size comparisons (Bearpaw Shale Formation).

Picture Credit: Everything Dinosaur

The palaeontologists conclude that the neck of Nakonanectes was about 2.3 metres long.  It is difficult to accurately date the strata that makes up the Bearpaw Shale Formation.  These two very different elasmosaurids may not have co-existed, but the discovery of Nakonanectes indicates that there was considerable variety in the neck length of members of the Elasmosauridae.  It also suggests that as the Cretaceous period progressed so at least one lineage of Elasmosaurs evolved shorter necks.

David Bradt Next to the Fossils (2010)

David Bradt with his fossil find.

Hunter David Bradt photographed in the stream bed with the fossils.

Picture Credit: David Bradt

The scientific paper: “A New Elasmosaurid (Sauropterygia, Plesiosauria) from the Bearpaw Shale (Late Cretaceous, Maastrichtian) of Montana Demonstrates Multiple Evolutionary Reductions of Neck Length within Elasmosauridae”, by Serratos, D. J., P. Druckenmiller, and R. B. J. Benson published in the Journal of Vertebrate Palaeontology.

15 04, 2017

New Tiny Dromaeosaurid from the Jehol Biota

By | April 15th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Zhongjianosaurus yangi from the Early Cretaceous of China

Researchers from the Chinese Academy of Sciences have published information on-line about the discovery of another dromaeosaurid from the Lower Cretaceous Yixian Formation of Liaoning Province (north-eastern China).  The little, long-legged “raptor”, that measured around eighty centimetres in length has been described as looking like “Microraptor on silts”.  The dinosaur has been named Zhongjianosaurus yangi, in honour of Yang Zhongjian regarded as the founder of vertebrate palaeontology in China.  The forelimbs are nearly as robust as the back legs which is a little unusual.  In addition, the ulna (bone in the lower arm), is longer than the humerus (upper arm bone), an anatomical feature that this dinosaur shares with many volant (capable of flight), birds.  The forelimb anatomy of Z. yangi contrasts with the anatomy of most non-avian Theropods, where the ulna is almost always much shorter than the humerus.

A Skeletal Drawing and an Illustration of Zhongjianosaurus yangi

Skeletal drawing and illustration.

Zhongjianosaurus fossil material (in white) shown in a skeletal drawing with a scientific illustration below.

Picture Credit: Chinese Academy of Sciences

In the skeletal drawing (above) the fossil material assigned to Z. yangi is shown in white.  Note the skull has not been found (scale bar equals five centimetres).

Eight Dromaeosaurid Species from the Jehol Group – Niche Partitioning 

The dromaeosaurids, which are a group of maniraptoran Theropods, are globally distributed and they have left a relatively extensive fossil record, but the earliest representatives of the Dromaeosauridae family come from the Lower Cretaceous Jehol Group of western Liaoning Province.  So far, a total of eight dromaeosaurid species have been reported from the Jehol Group, they are remarkably diverse and show numerous differences in their body plans which indicate that each type of dromaeosaurid was adapted to a different habitat or niche in the ecosystem.  This newly described dinosaur, Zhongjianosaurus yangi, classified from a single slab of fossilised bones continues this trend for Dromaeosaur diversity.  It is many times lighter than the largest dromaeosaurid (Tianyuraptor ostromi), known from this locality.  With an estimated 0.31 kilogramme mass, the Z. yangi holotype representing an adult individual, confirms that some Jehol dromaeosaurids are among the smallest known non-avialan Theropods described to date.

The Holotype Fossil Material (Post-cranial Material) of Z. yangi

The holotype fossil material of Zhongjianosaurus yangi.

The holotype of Zhongjianosaurus yangi.

Picture Credit: Chinese Academy of Sciences

Zhongjianosaurus yangi has been assigned to the Microraptorinae sub-family and the single fossil specimen was excavated from strata representing lake deposits in Sihedang, Lingyuan County, (western Liaoning).  The ninth dromaeosaurid of the Jehol Biota is difficult to date accurately, as Sihedang strata lacks biostratigraphical markers.  Z. yangi has been tentatively dated to the Aptian faunal stage of the Early Cretaceous (125 million-years-ago approximately).   Many of the other Dromaeosaur fossils have been retrieved from private collections and they subsequently lack stratigraphical context.  However, even if all nine different types of dromaeosaurid did not live at the same geological time they certainly represent a very disparate group and this suggests that these little dinosaurs adapted to different habitats and perhaps sources of food (niche partitioning).

Galapagos Finches

As reported in the advanced on-line publication, the researchers, Xing Xu and Zi-Chuan Qin propose that this collection of dromaeosaurids demonstrates niche partitioning and they compare the Jehol Dromaeosaurs to Darwin’s Galapagos finches.  Darwin noted that although the finches on the various islands that make up the Galapagos shared a common ancestor, they showed remarkable diversity in beak form and function.

In the absence of cranial material, it is not possible to identify what the tiny Zhongjianosaurus ate, but it is postulated that it could have been an insectivore, perhaps living high up in the tree canopy to escape the fast-running, larger hypercarnivores (other Dromaeosaurs), that roamed the forest floor.  Zhongjianosaurus was very probably feathered and those robust forelimbs could have supported wings that helped it to glide or flap its way from branch to branch.

The scientific paper: “A New Tiny Dromaeosaurid Dinosaur from the Lower Cretaceous Jehol Group of Western Liaoning and Niche Differentiation Among the Jehol Dromaeosaurids”, by Xing Xu and Zi-Chuan Qin (Chinese Academy of Sciences).

14 04, 2017

Moabosaurus of the Aptian of North America

By | April 14th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page|0 Comments

Moabosaurus utahensis – Adding to the Early Cretaceous Dinosaur Fauna of North America

Researchers from Brigham Young University writing in the University of Michigan’s Contributions from the Museum of Palaeontology, have published details of Utah’s latest dinosaur discovery, an Early Cretaceous Sauropod that roamed the western United States some 125 million-years-ago.  At a little under ten metres in length, Moabosaurus may not be the largest member of the Sauropodomorpha, but it remains a very significant dinosaur discovery nonetheless.  Compared to the earlier Morrison Formation fauna, not that much is known about the dinosaurs that roamed this part of the United States during the (Aptian faunal stage).  Moabosaurus, shared its lush, flood plain world, that was prone to prolonged droughts with dinosaurs such as Cedarosaurus (Sauropod) and Gastonia (armoured dinosaur), as well as a variety of Theropods.

The Mounted Skeleton (Composite) Ready for Display

Moabosaurus ready for display.

Brooks Britt, Brigham Young University geology professor, poses in front of Moabosaurus.

Picture Credit: Jaren Wilkey/Brigham Young University

Observant readers will note that the skull on this composite mount is actually a cast of a Camarasaurus skull.

The picture above shows Brigham Young University professor and lead author of the scientific paper, Brooks Britt, posing in front of the mounted exhibit of Moabosaurus (M. utahensis).  The fossils assigned to this new dinosaur genus, were all excavated from the Dalton Wells Quarry, some twelve miles north-west of the town of Moab (Utah).  Around 5,500 fragmentary bones were found entombed in the mudstone, the majority of which represents Moabosaurus, although the fossils were badly damaged, in part due to being trampled by other dinosaurs and from insect damage (probably beetle larvae), that fed on the bones when they had been initially buried.  Based on braincase sampling and other fossil finds, the researchers have suggested that at least eighteen individuals are represented.  The bones were also transported a short distance by water and buried in sediments reworked from the much older Morrison Formation.

Dalton Wells Quarry – Yellow Cat Member of the Cedar Mountain Formation

The preparation of a shattered femur which measures around 1.3 metres in length indicates that this dinosaur grew to about 9.75 metres in size.  Everything Dinosaur team members estimate that this herbivore might have weighed as much as an African elephant.  Palaeontologists tend to agree that, based on the current evidence, there was a substantial decline of Sauropod diversity in North America from the Late Jurassic and into the Early Cretaceous.

As to where Moabosaurus fits into the Sauropod family tree, that remains open to debate.  The researchers, which included Brigham Young University Museum of Palaeontology Curator Rod Scheetz and biology professor Michael Whiting plus a co-worker from Auburn University (Alabama), carried out four different taxonomic assessments using three different data sets.  Moabosaurus has been identified as a Neosauropod, two studies indicate that this dinosaur has affinities with the Macronaria, as such, it is regarded as a basal Titanosauriform.   It has been proposed that Moabosaurus was closely related to Turiasaurus (T. riodevensis) of the Early Cretaceous of Spain and Tendaguria (T. tanzaniensis) from the Late Jurassic of Tanzania.  Further phylogenetic studies will help to define the exact position of Moabosaurus in the Sauropod family tree.

A View of the Mounted Exhibit of Moabosaurus

A view of Moabosaurus.

Professor Brooks Britt poses in the body cavity of Moabosaurus.

Picture Credit: Jaren Wilkey/Brigham Young University

If Moabosaurus is closely related to Turiasaurus and Tendaguria then it suggests that land bridges may have existed between Gondwana and Laurasia to permit the mixing of faunas for longer into the Cretaceous than previously thought.  Analysis of zircon crystals, remnants of volcanic activity, indicate that Moabosaurus lived during the very earliest part of the Aptian faunal stage.  The phylogeny of Moabosaurus remains contentious.  In the scientific paper, “Moabosaurus utahensis – A New Sauropod from the Early Cretaceous of North America”, there is some discussion as to whether Nemegtosaurus and Quaesitosaurus (both from the Late Cretaceous of Mongolia), are sister taxa.

Examining the Sturdy Ribs of Moabosaurus

Moabosaurus being examined.

Moabosaurus and Geology Professor Brooks Britt.

Picture Credit: Jaren Wilkey/Brigham Young University

Perished in a Severe Drought

A previous study indicated that a large number of Moabosaurus and other dinosaurs died in a severe drought.  Survivors trampled their fallen companions’ bodies, smashing and crushing their bones.  After the drought ended, streams eroded the land, and transported the bones a short distance, where they were again trampled.  Meanwhile, insects in the soils fed on the bones, leaving behind tell-tale burrow marks.

Professor Britt stated:

“We’re lucky to get anything out of this site.  Most bones we find are fragmentary, so only a small percentage of them are usable and that’s why it took so long to get this animal put together.  We had to collect huge numbers of bones in order to get enough that were complete.”

13 04, 2017

The Dinosaurian Body Plan Alan Charig Remembered

By | April 13th, 2017|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Main Page, Photos/Pictures of Fossils|0 Comments

Teleocrater rhadinus and Dr Alan Charig

There’s a book on our office shelves, its dust jacket is faded and torn and the pages are yellowed with age, not surprising really as it was printed in 1973.  Although many of the passages, diagrams and ideas contained within it, have long since been superseded, it is treated with great reverence as it is one of the first dinosaur books I ever owned.  Entitled “Before the Ark” it accompanied a ten-part television series on vertebrate palaeontology produced by the BBC.  Written by Alan Charig and Brenda Horsfield, (Dr Charig wrote and presented the television series too), it remains a treasured possession and today, with the publication of a scientific paper in the journal “Nature”, we remember Dr Charig, a man who is still having an influence on science, even though he passed away some twenty years ago.

“Before the Ark” and Teleocrater – Tribute to Dr Alan Charig

"Before the Ark" and Teleocrater.

“Before the Ark” and Teleocrater (before the dinosaurs).

Picture Credit: BBC with T. rhadinus artwork by Gabriel Lio (Museo Argentino de Ciencias Naturales)

Early Dinosaur Cousin with “Crocodile-like Appearance”

Writing in the journal “Nature”, the researchers which include Sterling Nesbitt, assistant professor of geosciences at Virginia Tech, Roger Smith (University of Witwatersrand) and Paul Barrett of the Natural History Museum (London), describe more complete fossil material relating to Teleocrater rhadinus and formally establish this genus which helps to fill a critical gap in the fossil record leading to the evolution of the dinosaurs.

Teleocrater (the name means “slender complete basin” in reference to the reptile’s light build and the fully closed hip socket), was first proposed by Alan Charig back in the 1950’s.  He was a PhD student at Cambridge University writing a doctoral thesis on Triassic reptiles of Tanganyika (now Tanzania).  Alan was being supervised by Francis Rex Parrington, a vertebrate palaeontologist who had uncovered the very first fossils of what we now refer to as Teleocrater rhadinus, during fieldwork in Tanganyika in 1933.

Fieldwork undertaken in 2015, led to the discovery of more fossil material and crucially limb elements and ankle bones which have helped determine where amongst the Archosaurs Teleocrater should be placed.

Fieldwork in Tanzania (2015)

Excavating the fossils of Teleocrater and other Triassic animals.

Excavating the remains of Teleocrater rhadinus and other animals in southern Tanzania in 2015.

Picture Credit: Roger Smith

The photograph above shows authors Christian Sidor (left), Sterling Nesbitt, Kenneth Angielczyk (in the purple top and white floppy hat), along with Michelle Stocker (right), looking for Triassic vertebrates in exposures of the Manda Beds (Anisian faunal stage of the Middle Triassic) of southern Tanzania.

All Fossil Material from the Manda Beds

Francis R. Parrington collected the first fossil specimens from the Manda Beds in the Ruhuhu Basin of southern Tanzania.  These fossils were studied by Alan Charig for his doctorate, but much of Alan’s work on Teleocrater was never published.  Dr Charig went to Tanzania to search for more fossils in 1963, but it was not until the expedition of 2015, that the crucially important limb and ankle bones were recovered that demonstrated where on the Archosauria family tree Teleocrater should sit.

The ankle bones and other skeletal elements demonstrate that Teleocrater is more closely related to dinosaurs and birds than it is to crocodiles. It sits on the family tree of the Archosaurs at the base of the Avemetatarsalian branch, the “bird-line Archosaurs”, sometimes also referred to as the Ornithodira.  The researchers conclude that Teleocrater and its near relatives split off from other Avemetatarsalians before the evolutionary split between the Pterosauria (flying reptiles) and the dinosaurs.

Establishing T. rhadinus on the Archosauria Family Tree

The phylogeny of Teleocrater.

Teleocrater is more closely related to the Pterosauria and the Dinosauria (including Aves) than to crocodilians.

Picture Credit: Sterling Nesbitt of Virginia Tech with additional annotation by Everything Dinosaur

The Big Two Branches of the Archosauria

The Archosauria clade consists of birds and crocodiles plus an array of extinct creatures which include the dinosaurs, silesaurids and the flying reptiles (pterosaurs).  This huge group of reptiles can be generally divided up into two distinct branches, based on the anatomy of the ankle bones.  On one branch, we have the crocodiles and their relatives (Crurotarsi), which tend to have a sprawling gait, whilst on the other branch we have the Avemetatarsalia, otherwise referred to as the Ornithodirans, which tend to have their limbs directly under their hips and have a more upright gait, similar to mammals.

Dr Charig never got the opportunity to study fossils of the ankle bone, he passed away in 1997, without being able to complete his assessment of this reptile.  The researchers have honoured the contribution made by Alan Charig by naming him as an author on the 2017 paper and formally recognising the name Teleocrater, that he was the first to use.

Excavating the Fossils of Teleocrater

Excavating the fossils of Teleocrater and other Triassic animals.

Sterling Nesbitt (left) and Christian Sidor (right) working on some fossil bones.

Picture Credit: Roger Smith

Uniting the Aphanosauria Clade – Dinosaur Ancestors on All Fours

Teleocrater helps to cement the establishment of the Aphanosauria clade, a group of long-necked, slender-limbed, carnivores that lived in the Middle Triassic and were geographically widespread across Pangaea.  The Crurotarsi Archosaurs, those crocodile-like creatures were thought to be highly diversified and geographically widespread across the super-continent Pangaea.  It now seems that the other branch of the Archosauria, the Avemetatarsalia, may have been equally as diverse and as widespread as their crocodile-like cousins.

Previously, palaeontologists have postulated that the earliest dinosaur relatives were chicken-sized and bipedal.  Thanks to the 2015 fossil discoveries and the work first undertaken by F. R. Parrington and Alan Charig, scientists have a different body plan to consider.  T. rhadinus which roamed the area that was to become Tanzania some 245 million-years-ago, was much larger at around three metres long and it was a quadruped.

An Illustration of the Early Avemetatarsalian Teleocrater rhadinus

T. rhadinus illustration.

A life reconstruction of Teleocrater rhadinus.

Picture Credit:  Gabriel Lio (Museo Argentino de Ciencias Naturales)

Alan Charig studied the fossils of what we now know as Teleocrater rhadinus.  Twenty years after his death, scientists can place this enigmatic reptile and its relatives within the Avemetatarsalian branch of the Archosauria, Teleocrater represents one of the earliest members of this sub-branch, a lineage that eventually led to the dinosaurs and the birds.

In addition, with a more complete picture of Teleocrater, palaeontologists have another puzzle to ponder.  If the early branch members of the Avemetatarsalia were more species-rich and more widely geographically distributed than previously thought, then several early Dinosauromorphs used to help scientists to understand how the body plan of the Dinosauria evolved, may represent specialised forms rather than the typical ancestral Avemetatarsalian body plan.

Today, we reflect on the work of Dr Alan Charig and his mentor Francis Rex Parrington.  The researchers writing in the journal “Nature” have helped to put flesh onto those bones first examined all those years ago.  For my part, my thanks to Alan Charig for helping to write such a beautiful book and for inspiring a generation of science writers and enthusiasts.

The scientific paper: “The Earliest Bird-line Archosaurs and he Assembly of the Dinosaur Body Plan” by Sterling J. Nesbitt, Richard J. Butler, Martín D. Ezcurra, Paul M. Barrett, Michelle R. Stocker, Kenneth D. Angielczyk, Roger M. H. Smith, Christian A. Sidor, Grzegorz Niedźwiedzki, Andrey G. Sennikov & Alan J. Charig published in the journal “Nature”.

Everything Dinosaur acknowledges the help of Virginia Tech in the compilation of this article.

12 04, 2017

Chinese Fossil Sites Under Threat

By | April 12th, 2017|Dinosaur and Prehistoric Animal News Stories, Main Page, Photos/Pictures of Fossils|0 Comments

Mining Operations Damage Famous Fossil Site

An article in the South China Morning Post highlights the growing concern expressed by the scientific community over damage to a globally important fossil site in Guizhou Province (south-western China).  Phosphorous mining operations are wiping away fossil evidence of some of the earliest organisms classified as animals known to science.  The tiny micro-fossils preserved in strata exposed in Weng’an county, represent the remains of multi-cellular organisms, marine sponges that once thrived in an ancient sea some 600 million years ago.

A False Colour Image Showing One of the Sponge-Like Micro-fossils (Doushantuo Formation)

Sponge-like Ediacaran micro-fossil.

A scanning electron microscope image of the 600 million-year-old sponge-like animal fossil (false colour image).

Picture Credit: NIGPAS (Chinese Academy of Sciences)

Professor Zhu Maoyan and his colleagues at the Nanjing Institute of Geology and Palaeontology have called for urgent measures to be taken to help protect the Weng’an biota.  The world-renowned fossil site, one of the few places that preserves traces of Ediacaran fauna, is threatened as hundreds of mining trucks are transporting rocks from the area every day.  Weng’an county has one of Asia’s largest phosphorus reserves.  The mining business contributes more than sixty per cent of the county government’s annual tax income.  Intensive mining in the area has led to cases of massive subsidence.

The professor, who has led a number of field teams to explore the fossiliferous sediments, that first came to the attention of palaeontologists less than twenty years ago, stated:

“Six hundred million years of life’s evolutionary history is being traded to help produce a bowl of rice.”

The demand for phosphorous to make fertiliser is increasing, unfortunately, the rocks that form the Doushantuo Formation of Guizhou Province are a rich source of this important element.  However, local officials in Weng’an county have promised action after a fossil site covering about three square kilometres was nearly destroyed and buried under huge heaps of debris caused by subsidence.

The micro-fossils preserved in the phosphorite rocks of the Doushantuo Formation, preserve the remains of 600 million-year-old, sponge-like organisms.  Professor Zhu commented that the Weng’an biota was remarkable because of the abundance of fossils and their fine state of preservation, with details shown down to a cellular level.

The professor added:

“There may not be another place like it in the whole world.”

Features of the Fossils are Similar to Extant Sponge Anatomy

Precambrian sponge-like fossils.

Views of the sponge-like fossils from south-western China.

Picture Credit: NIGPAS (Chinese Academy of Sciences)

The picture above shows various views of micro-fossils from the Weng’an county location including highly magnified views of what be a holdfast structure (c, d, e, f, g and h).

Professor Zhu stressed that both local government and the public had failed to realise that the exposures in Weng’an county are unique and very valuable to science.  It was suggested that a “core area” be chosen and then this site given protection.

To read an article featuring research by Virginia Tech College of Science and the Chinese Academy of Sciences which looks at the fossil evidence from the Doushantuo Formation: New Research Suggests Multicellular Life Started Earlier Than Previously Thought

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