The Description of Ceratopsian Yinlong downsi's Cranial Anatomy

Cranial anatomy of Yinlong downsi (Ornithischia: Ceratopsia) from the Upper Jurassic Shishugou Formation of Xinjiang, China

Authors:

Han et al

Abstract:

Yinlong downsi, from the Upper Jurassic Shishugou Formation, Xinjiang, northwestern China, is the oldest known ceratopsian dinosaur. Here we provide a detailed description of the skull and mandible based on the holotype, three partial skulls, and disarticulated materials from several other specimens. Yinlong can be diagnosed by six autapomorphies: a distinct fossa along the midline of the frontals; a slit-like carotid canal bordered by laminae; premaxillary teeth with a vertical wear facet and a basal shelf; a deep sulcus on the ventral surface of the quadratojugal; large oval nodules concentrated on the lateral surface of the jugal; and a squamosal with an expanded dorsal surface and a long, constricted quadrate process. A detailed comparison with other basal ceratopsians suggests that Yinlong downsi may belong within Chaoyangsauridae. Yinlong also shares many derived characters both with Psittacosaurus and neoceratopsians, suggesting that character evolution in early ceratopsians is complex. Additionally, a caniniform premaxillary tooth is present in one small specimen (IVPP V18636), which may suggest sexual dimorphism or individual variation.

Ankylosaur Hungarosaurus may Have Had a Cursorial Lifestyle in the Santonian Cretaceous

Partial skull and endocranial cast of the ankylosaurian dinosaur Hungarosaurus from the Late Cretaceous of Hungary: implications for locomotion

Authors:

Ősi et al

Abstract:

A partial skull of ankylosaur from the Upper Cretaceous (Santonian) Csehbánya Formation in Iharkút and the endocranial cast taken from it are described. The morphology of the exoccipital, the elongated 'neck' region of the basioccipital, the shape of the occipital condyle, and the different flexure of the medulla relative to the forebrain unambiguously differentiate this specimen from the basicranium of Struthiosaurus, so it is assigned to Hungarosaurus sp. Whereas the endocranial cast reflects a brain generally similar to those of other ankylosaurs, the dorsally hypertrophied cerebellum (also present is Struthiosaurus transylvanicus) is quite unusual within the group suggesting a more sophisticated cerebral coordination of posture and movement, and perhaps a more cursorial locomotary habit than predicted for other ankylosaurs.

Edmontosauraus regalis: The Duck-billed Dinosaur who Sported a Chicken's Crest

A rare, mummified specimen of the duck-billed dinosaur Edmontosauraus regalis described in the Cell Press journal Current Biology on December 12 shows for the first time that those dinosaurs' heads were adorned with a fleshy comb, most similar to the roosters' red crest.

The most common dinosaurs in North America between 75 and 65 million years ago, duck-billed dinosaurs were gentle giants, about 12 meters long, and filled the same ecological role that kangaroos or deer play today. But no one had suspected that they—or other dinosaurs, for that matter—had fleshy structures on the tops of their heads.

"Until now, there has been no evidence for bizarre soft-tissue display structures among dinosaurs; these findings dramatically alter our perception of the appearance and behavior of this well-known dinosaur and allow us to comment on the evolution of head crests in this group," says Phil Bell from Australia's University of New England. "It also raises the thought-provoking possibility of similar crests among other dinosaurs."

The dinosaur specimen in question was found in deposits west of the city of Grande Prairie in west-central Alberta, Canada. Bell, along with Federico Fanti from the University of Bologna, Italy, knew they had something special when they found skin impressions on parts of the mummified body. But it wasn't until Bell put a chisel through the top of the crest that he realized they really had something incredible.

"An elephant's trunk or a rooster's crest might never fossilize because there's no bone in them," Bell explains. "This is equivalent to discovering for the first time that elephants had trunks. We have lots of skulls of Edmontosaurus, but there are no clues on them that suggest they might have had a big fleshy crest. There's no reason that other strange fleshy structures couldn't have been present on a whole range of other dinosaurs, including T. rex or Triceratops."

Of course, it's hard to tell what that cocks comb might have done for the duck-billed dinosaurs. In roosters and some other birds, bright red crests are a way to get the girls. "We might imagine a pair of male Edmontosaurus sizing each other up, bellowing, and showing off their head gear to see who was the dominant male and who is in charge of the herd," Bell says.

link.

Europelta carbonensis: a new Albian Cretaceous Nodosaurid Anklyosaur From Spain

The basal nodosaurid ankylosaur Europelta carbonensis n. gen., n. sp. from the Lower Cretaceous (lower Albian) Escucha Formation of northeastern Spain

Authors:

Kirkland et al

Abstract:

Nodosaurids are poorly known from the Lower Cretaceous of Europe. Two associated ankylosaur skeletons excavated from the lower Albian carbonaceous member of the Escucha Formation near Ariño in northeastern Teruel, Spain reveal nearly all the diagnostic recognized character that define nodosaurid ankylosaurs. These new specimens comprise a new genus and species of nodosaurid ankylosaur and represent the single most complete taxon of ankylosaur from the Cretaceous of Europe. These two specimens were examined and compared to all other known ankylosaurs. Comparisons of these specimens document that Europelta carbonensis n. gen., n. sp. is a nodosaur and is the sister taxon to the Late Cretaceous nodosaurids Anoplosaurus, Hungarosaurus and Struthiosaurus, defining a monophyletic clade of European nodosaurids - the Struthiosaurinae.

Awesomely Intact Ceratopsid Chasmosaurus belli Juvenile Fossil Found From Campanian Cretaceous Canada

The tiny, intact skeleton of a baby rhinoceroslike dinosaur has been unearthed in Canada.

The toddler was just 3 years old and 5 feet (1.5 meters) long when it wandered into a river near Alberta, Canada, and drowned about 70 million years ago. The beast was so well-preserved that some of its skin left impressions in the nearby rock.

The fossil is the smallest intact skeleton ever found from a group of horned, plant-eating dinosaurs known as ceratopsids, a group that includes the iconic Triceratops.

link.

Hardrosaur Trackways From the Late Maastrichtian Bolster Bollide Impact Extinction for KT/K-Pg Extinction

The Latest Succession of Dinosaur Tracksites in Europe: Hadrosaur Ichnology, Track Production and Palaeoenvironments

Authors:

1. Bernat Vila (a,b)
2. Oriol Oms (c)
3. Víctor Fondevilla (c)
4. Rodrigo Gaete (d)
5. Àngel Galobart (b)
6. Violeta Riera (c)
7. José Ignacio Canudo (a)

Affiliations:

a. Grupo Aragosaurus–IUCA, Paleontología, Facultad de Ciencias Universidad de Zaragoza, Zaragoza, Spain

b. Institut Català de Paleontologia Miquel Crusafont, Sabadell, Barcelona, Spain

c. Departament de Geologia (Estratigrafia), Facultat de Ciències Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain

d. Museu de la Conca Dellà, Isona i Conca Dellà, Lleida, Spain

Abstract:

A comprehensive review and study of the rich dinosaur track record of the Tremp Formation in the southern Pyrenees of Spain (Southwestern Europe) shows a unique succession of footprint localities prior to the end-Cretaceous mass extinction event. A description of some 30 new tracksites and data on sedimentary environments, track occurrence and preservation, ichnology and chronostratigraphy are provided. These new track localities represent various facies types within a diverse set of fluvial environments. The footprint discoveries mostly represent hadrosaurian and, less abundantly, to sauropod dinosaurs. The hadrosaur tracks are significantly smaller in size than, but morphologically similar to, those of North America and Asia and are attributable to the ichnogenus Hadrosauropodus. The track succession, with more than 40 distinct track levels, indicates that hadrosaur footprints in the Ibero-Armorican region occur predominantly in the late Maaastrichtian (at least above the early Maastrichtian–late Maastrichtian boundary). The highest abundance is found noticeably found in the late Maastrichtian, with tracks occurring in the C29r magnetochron, within about the latest 300,000 years of the Cretaceous.

paper link.

Brian's pop sci short write up.

Dodson et al Lump Three Psittacosaurus Species into One

A new analysis of dinosaur fossils by University of Pennsylvania researchers has revealed that a number of specimens of the genus Psittacosaurus — once believed to represent three different species — are all members of a single species. The differences among the fossil remains that led other scientists to label them as separate species in fact arose from how the animals were buried and compressed, the study found.

"Because of the vagaries of fossilization, no two fossils are the same," said senior author Peter Dodson, professor of anatomy in Penn's School of Veterinary Medicine and professor of paleontology in the School of Arts and Sciences' Department of Earth and Environmental Science. "Animals are alive and they die, but what's crucial in paleontology is what happens to the animals after they die."

The research involved a cutting-edge technique, known as three-dimensional geometric morphometrics, which uses lasers to generate data about the shape of different specimens. This is the first time the approach has been used to study dinosaur fossils and could lead to a re-examination of the taxonomic classifications of additional dinosaur species as well as other long-extinct fossil organisms.

Brandon Hedrick, a doctoral student in the Department of Earth and Environmental Science, led the study in collaboration with Dodson. Their research will be reported in the journal PLOS ONE.

The investigation focused on dinosaurs in the genus Psittacosaurus, a word that comes from the Greek for "parrot lizard." The group was named for the animal's beaked face, not unlike that of a turtle. Originally discovered in 1923, 15 species have been classified as Psittacosaurus, though a recent analysis confirmed only nine of these as definite members of the genus. These animals were small plant-eaters that lived 120 to 125 million years ago. Paleontologists have discovered Psittacosaurus fossils in Mongolia, China and Russia and possibly in Thailand.

"Meat-eaters are sexy; plant-eaters are not," Dodson said. "This isn't a flashy dinosaur. But it has an interesting feature in that it's one of the most abundant dinosaurs known to science."

Indeed, many hundreds of Psittacosaurus specimens have been found. This abundance made the genus ideal for Hedrick and Dodson's comparative study, as it is easier to determine relationships within and between species when there are more individuals to compare.

"For example, if you have a single dachshund and a single beagle, they may appear to be different species until you found 40 dachshund-beagle mixes of various grades to examine," Hedrick said.

The scientists examined Psittacosaurus skulls discovered in the fossilized ashes of the Lujiatun beds of northeastern China's Yixian Formation. Paleontologists had previously identified the skulls as belonging to three different species, Psittacosaurus lujiatunensis, P. major or Hongshanosaurus houi.

To compare and contrast the specimens, the researchers used two techniques. First they conducted a traditional study in which they examined every skull that had been classified as one of those three species — a total of 74 specimens — for a variety of characteristics that had been used in prior studies to distinguish the species. The Penn team also compared these fossils to skulls that had been classified as belonging to eight other Psittacosaurus species.

Next they completed a more high-tech analysis of 30 skulls from the three named species. Using a hand-held stylus that captures a point in space relative to a transmitter, they pinpointed 56 "landmarks," or particular anatomical locations, on each fossil and compared the relative position of those marks between specimens. They also used a hand-held, laser-emitting scanner to make a three-dimensional image of each specimen, similar to a CT scan, from which they also collected landmark data.

Based on the "old-fashioned" method of examining the physical skulls, the researchers concluded that the three purported species were in fact one. They propose that all three can be considered members of the species P. lujiatunensis.

Albertadromeus syntarsus: A New Orinthopod Dinosaur From the Campanian of Canada

Dinosaurs are often thought of as large, fierce animals, but new research highlights a previously overlooked diversity of small dinosaurs. In the Journal of Vertebrate Paleontology, a team of paleontologists from the University of Toronto, Royal Ontario Museum, Cleveland Museum of Natural History and University of Calgary have described a new dinosaur, the smallest plant-eating dinosaur species known from Canada. Albertadromeus syntarsus was identified from a partial hind leg, and other skeletal elements, that indicate it was a speedy runner. Approximately 1.6 m (5 ft) long, it weighed about 16 kg (30 lbs), comparable to a large turkey.

Albertadromeus lived in what is now southern Alberta in the Late Cretaceous, about 77 million years ago. Albertadromeus syntarsus means "Alberta runner with fused foot bones". Unlike its much larger ornithopod cousins, the duckbilled dinosaurs, its two fused lower leg bones would have made it a fast, agile two-legged runner. This animal is the smallest known plant-eating dinosaur in its ecosystem, and researchers hypothesize that it used its speed to avoid predation by the many species of meat-eating dinosaurs that lived at the same time.

Albertadromeus was discovered in 2009 by study co-author David Evans of the Royal Ontario Museum as part an on-going collaboration with Michael Ryan of the Cleveland Museum of Natural History to investigate the evolution of dinosaurs in the Late Cretaceous of North America. The known dinosaur diversity of this time period is dominated by large bodied plant-eating dinosaurs.

Acrotholus audeti: a New Miniature Pachycephalosaur from Santonian Cretaceous Canada

Scientists have named a new species of bone-headed dinosaur (pachycephalosaur) from Alberta, Canada. Acrotholus audeti (Ack-RHO-tho-LUS) was identified from both recently discovered and historically collected fossils. Approximately six feet long and weighing about 40 kgs in life, the newly identified plant-eating dinosaur represents the oldest bone-headed dinosaur in North America, and possibly the world. Research describing the new species is published May 7, 2013 in the journal Nature Communications.

Acrotholus means "high dome", referring to its dome-shaped skull, which is composed of solid bone over 10 centimeters (two inches) thick. The name Acrotholus audeti also honors Alberta rancher Roy Audet, on whose land the best specimen was discovered in 2008. Acrotholus walked on two legs and had a greatly thickened, domed skull above its eyes, which was used for display to other members of its species, and may have also been used in head-butting contests. Acrotholus lived about 85 million years ago.

The new dinosaur discovery is based on two skull 'caps' from the Milk River Formation of southern Alberta. One of these was collected by the Royal Ontario Museum (ROM) over 50 years ago. However, a better specimen was found in 2008 by University of Toronto graduate student Caleb Brown during a field expedition organized by Dr. David Evans of the Royal Ontario Museum and University of Toronto, and Dr. Michael Ryan of The Cleveland Museum of Natural History.

"Acrotholus provides a wealth of new information on the evolution of bone-headed dinosaurs. Although it is one of the earliest known members this group, its thickened skull dome is surprisingly well-developed for its geological age," said lead author Dr. David Evans, ROM Curator, Vertebrate Palaeontology. "More importantly, the unique fossil record of these animals suggests that we are only beginning to understand the diversity of small-bodied plant-eating dinosaurs."

Small mammals and reptiles can be very diverse and abundant in modern ecosystems, but small dinosaurs (less than 100 kg) are considerably less common than large ones in the fossil record. Whether this pattern is a true reflection of dinosaur communities, or is related to the greater potential for small bones to be destroyed by carnivores and natural decay, has been debated. The massively constructed skull domes of pachycephalosaurs are resistant to destruction, and are much more common than their relatively delicate skeletons – which resemble those of other small plant-eating dinosaurs. Therefore, the researchers suggest that the pachycephalosaur fossil record can provide valuable insights into the diversity of small, plant-eating dinosaurs as a whole.

"We can predict that many new small dinosaur species like Acrotholus are waiting to be discovered by researchers willing to sort through the many small bones that they pick up in the field," said co-author Dr. Michael Ryan, curator of vertebrate paleontology at The Cleveland Museum of Natural History. "This discovery also highlights the importance of landowners, like Roy Audet, who grant access to their land and allow scientifically important finds to be made."

A pop sci write up.

Paper link.

New Psittacosaurus species

The new dinosaur, Psittacosaurus gobiensis, resembled a modern parrot on steroids, but it was likely not a close relative.

"Psittacosaurus discovered the delights of nut eating 110 million years ago, at least 60 million years before the first parrot arrived," lead author a Paul Sereno told Discovery News.

Sereno, a University of Chicago paleontologist, with colleagues Zhao Xijin and Tan Lin analyzed the remains of the parrot-like dinosaur, which was first unearthed in the western Gobi Desert of inner Mongolia back in 1922. The fossils represent the first and most complete dinosaur excavated in that region at the time.

Sereno and his team, whose findings are published in the latest Proceedings of the Royal Society B, not only identified the new species, but they were also able to determine how, and what, it ate.

Analysis of its skull shows it had reinforcements and "enhanced attachment areas for powerful jaw muscles," as today's parrots do around their beaks. These clues, along with visible tooth wear, allowed the scientists to figure out how the dinosaur bit down on its food.

"Parrot-beaked dinosaurs chewed by sliding their lower jaw forward and then drawing it upward and backward against its upper teeth -- very unusual," said Sereno. "The vast majority of reptiles either just clamp the jaws shut or slide them forward and backward to grind."

No time to comment, but I know most of my readers love the paleo stuff. However, I doubt that this was 60 million years old. (oops!)

Murder in the Mesozoic

The discovery of a gruesome feeding frenzy that played out 73 million years ago in northwestern Alberta may also lead to the discovery of new dinosaur species in northwestern Alberta.

University of Alberta student Tetsuto Miyashita and Frederico Fanti, a paleontology graduate student from Italy, made the discovery near Grande Prairie, 450 kilometres northwest of Edmonton.

Miyashita and Fanti came across a nesting site and found the remains of baby, plant-eating dinosaurs and the teeth of a predator. The researchers matched the teeth to a Troodon, a raptor-like dinosaur about two metres in length. This finding has opened new doors in dinosaur research on this part of the continent: "It established that dinosaurs were nesting at this high latitude," said Miyashita. "It also shows for the first time a significant number of Troodons in the area [who] hunted hatchling dinosaurs."

Over the course of two summers of field work Miyashita and Fanti began building a theory that Grande Prairie is a "missing link" between known dinosaur species that existed much further to the north and south. "Prior to this there were no localities with a variety of dinosaurs and other animals between Alaska and southern Alberta," said Myiashita. The list of new finds for the area includes armoured and thick-headed plant eaters and fossilized freshwater fish and reptiles.

Miyashita says this small pocket of previously undiscovered life could have had interactions that lead to the evolution of new species.

"New dinosaurs weren't created by interbreeding," said Miyashita. "Having a variety of dinosaurs in one area creates new ecological interactions such as competition for food and predation.

"That can lead to the evolution of a new species."

One Grande Prairie dinosaur the researchers suspect is a new species is the Duck bill. Miyashita says unlike the Duck bill found further north in Alaska, the Grande Prairie has a visible bump or crest on its forehead.

I wonder what the size difference between the Troodons is there and in Alaska and further south. New hadrosaur! Yeah! Let's increase the diversity!!!

Hadrosaur Proteins, Blood Cells, Blood Vessels Recovered

Ancient protein dating back 80 million years to the Cretaceous geologic period has been preserved in bone fragments and soft tissues of a hadrosaur, or duck-billed dinosaur, according to a study in the May 1 issue of Science. Led by scientists at Beth Israel Deaconess Medical Center (BIDMC) and North Carolina State University (NCSU), the new findings support earlier results from analyses suggesting that collagen protein survived in the bones of a well preserved Tyrannosaurus rex, and offer robust new evidence supporting previous conclusions that birds and dinosaurs are evolutionarily related.

In April 2007 John Asara, PhD, Director of the Mass Spectrometry Core at BIDMC, together with NCSU paleontologist Mary Schweitzer, PhD, published two papers in Science describing their discovery that collagen extracted from bone fragments of a 68-million-year-old T. rex closely matched the amino acid sequences of modern day chickens. Not surprisingly, the widely publicized findings created a great deal of controversy.

"With this new paper, we hoped to show that our T. rex discovery was not a unique occurrence," notes Asara, who is also an Instructor in Pathology at Harvard Medical School. "This is the second dinosaur species we've examined and helps verify that our first discovery was not just a one-hit wonder. Our current study was the collaborative effort of a number of independent laboratories, whose findings collectively add up to a robust conclusion."

At the heart of the controversy is the idea that ancient protein can exist at all. When an animal dies, protein immediately begins to degrade and, in the case of fossils, is slowly replaced by mineral, a substitution process assumed to be complete by 1 million years. But with this latest evidence, it appears that some proteins do indeed have real staying power.

"We wound up identifying nearly double the number of amino acids we recovered in the T. rex study," says Asara. "The sequences displayed high spectral quality and the interpretations were of high confidence."

The two scientists had decided to collaborate again after Schweitzer and paleontologist Jack Horner of Montana State University's Museum of the Rockies recovered the 80-million-year-old Brachylophosaurus canadensis femur bone in the summer of 2007 and observed that it appeared to be even better preserved than the original T. rex fossil.

Schweitzer's initial laboratory analyses confirmed this observation: After being subjected to demineralization, the B. canadensis bone fragments showed marked preservation of original tissues and molecules, with microstructures resembling soft, transparent vessels, cells and fibrous matrix – even though the fossil was much older than the T. rex sample.

"Deep burial in sandstone seems to favor exceptional preservation," notes Schweitzer, explaining that this fossil was found under approximately seven meters of sandstone in the Judith River Formation, in parts of what is now Eastern Montana.

Chemical extractions of bone and vessel were subsequently sent to the laboratories of BIDMC scientists Lewis Cantley, PhD, and Raghu Kalluri, PhD, where immunoblots and immunochemistry analyses were conducted to determine the presence of collagen protein in the samples.

"Having been a part of the T. rex study, I was curious to be part of this investigation as well," explains Cantley, Chief of the Division of Signal Transduction at BIDMC. "In view of the skepticism about the original findings, it was important to demonstrate that our findings in T. rex could be verified in another dinosaur and in other laboratories."

The results confirmed the existence of protein. "Because I am a collagen biochemist, our lab was contacted to perform an independent analysis of this new bone find," explains Kalluri, who is Chief of the Division of Matrix Biology at BIDMC. "We isolated the proteins – collagen, laminin and elastin – from the bone, and also extracted bone cells and blood vessels from this sample. Our findings demonstrated that it did contain basement membrane matrix."

Dude. More comments later. Doing major maintenance at work.

Triceratops Gregariousness Confirmed?

Until now, Triceratops was thought to be unusual among its ceratopsid relatives. While many ceratopsids—a common group of herbivorous dinosaurs that lived toward the end of the Cretaceous—have been found in enormous bonebed deposits of multiple individuals, all known Triceratops (over 50 in total) fossils have been solitary individuals. But a new discovery of a jumble of at least three juveniles the badlands of the north-central United States suggests that the three-horned dinosaurs were not only social animals, but may have exhibited unique gregarious groupings of juveniles.

"This is very thrilling," says Stephen Brusatte, an affiliate of the American Museum of Natural History and a doctoral student at Columbia University. "We can say something about how these dinosaurs lived. Interestingly, what we've found seems to be a larger pattern among many dinosaurs that juveniles lived and traveled together in groups."

In 2005, Brusatte and colleagues found and excavated a site that contained multiple Triceratops juveniles in 66-million-year-old rocks in southeastern Montana. The geological evidence suggests that at least three juveniles were deposited at the same time by a localized flood, and this suggests that they were probably living together when disaster struck. This find indicates that Triceratops juveniles congregated in small herds, a social behavior increasingly identified in other dinosaur groups, such as Psittacosaurus, a small cousin of Triceratops that lived in Asia.

"We don't know why they were grouped together or how much time they spent together," says Joshua Mathews of the Burpee Museum of Natural History and Northern Illinois University, who led the project. "Herding together could have been for protection, and our guess is that this wasn't something they did full time."

Y'know, I could have sworn that Triceratops was confirmed to have lived in herds if not large ones...but what the heck, maybe not.

Just How Basal ARE Feathers for Dinosaurs?

An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures

Xiao-Ting Zheng1, Hai-Lu You2, Xing Xu3 & Zhi-Ming Dong3

1. Shandong Tianyu Museum of Nature, Lianhuashan Road West, Pingyi, Shandong, 273300, China
2. Institute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang Road, Beijing 100037, China
3. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 142 Xiwai Street, Beijing 100044, China

Correspondence to: Hai-Lu You2 Correspondence and requests for materials should be addressed to H.-L.Y. (Email: youhailu@gmail.com).

Top of page
Abstract

Ornithischia is one of the two major groups of dinosaurs, with heterodontosauridae as one of its major clades. Heterodontosauridae is characterized by small, gracile bodies and a problematic phylogenetic position1, 2. Recent phylogenetic work indicates that it represents the most basal group of all well-known ornithischians3. Previous heterodontosaurid records are mainly from the Early Jurassic period (205–190 million years ago) of Africa1, 3. Here we report a new heterodontosaurid, Tianyulong confuciusi gen. et sp. nov., from the Early Cretaceous period (144–99 million years ago) of western Liaoning Province, China. Tianyulong extends the geographical distribution of heterodontosaurids to Asia and confirms the clade's previously questionable temporal range extension into the Early Cretaceous period. More surprisingly, Tianyulong bears long, singular and unbranched filamentous integumentary (outer skin) structures. This represents the first confirmed report, to our knowledge, of filamentous integumentary structures in an ornithischian dinosaur.

1. Shandong Tianyu Museum of Nature, Lianhuashan Road West, Pingyi, Shandong, 273300, China
2. Institute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang Road, Beijing 100037, China
3. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 142 Xiwai Street, Beijing 100044, China

Link at the top is to the paper. First seen at Chinleana, but also at Not Exactly Rocket Science and on Yahoo News.


Since I first came across them, I have found the heterodontosaurs to be absolutely fascinating. The fact that they are now in Laurasia and made it to the Cretaceous, is just plain kewl. After all, here's a dinosaur that had freakin canines! (well, sorta canines) After ceratopsians, they're my favorites.

Why is the dating so loosely constrained?

For the phylogeny geeks: