Camarasaurus skull.


Camarasaurus Camarasaurus

paper Dinosaur / Lindahall

40. The Carnegie Juvenile Camarasaurus, 1925


The reason the Osborn/Mook memoir on Camarasaurus was described as “almost definitive” (see item 39) is that one year after its publication, a fully articulated and nearly complete skeleton of a juvenile Camarasaurus was recovered from the Carnegie quarry, which shortly after this find became the Dinosaur National Monument. This massive slab (actually four slabs, joined together after shipment from the quarry) was and is the most perfect sauropod skeleton ever discovered. In 1925 Gilmore described the specimen in this fully illustrated memoir. The photograph reproduced at upper left shows the specimen as it was when found.

The Museum decided to display the skeleton as a panel mount, and another photograph shows the fossil as displayed (see illustration at lower right). Comparing the two reveals that the skeleton was allowed to retain its original position, except that the tail was straightened out, a few displaced bones were re-articulated, and the missing left ilium was provided from another specimen. The flat bone found next to the tail is a sternal plate, which was placed beneath the neck in the final display.


The articulation of the bones allowed Gilmore to conclude that Camarasaurus did not have its highest elevation at the shoulders, as Osborn, Mook, and Christman had reconstructed it, but rather stood highest at the hips, like Apatosaurus and Diplodocus.

The monograph contains a large folding plate with a corrected restoration of the skeleton. The photographs were taken by Arthur S. Coggeshall, and the line drawings and the full skeletal restoration were the work of Sydney Prentice.

Source Gilmore, Charles W.      “A nearly complete articulated skeleton of Camarasaurus, a saurischian dinosaur from the Dinosaur National Monument, Utah,” in: Memoirs of the Carnegie Museum, vol. 10 (1925), pp. 347-384. This work was on display in the original exhibition as item 40.

Camarasaurus is een sauropode dinosauriër behorend tot de groep van de Camarasauromorpha. Dit dier werd 18 tot 20 meter lang. Hij leefde in het Late Jura net als vele andere sauropoden.

Bij het geslacht werden door Edward Drinker Cope en Othniel Charles Marsh verschillende soorten onderscheiden waarvan tegenwoordig in ieder geval nog de oorspronkelijke twee erkend worden: respectievelijk C.supremus en C.grandis, beiden uit 1877.

Het dier had geen kiezen om planten of vlees mee te vermalen. Hij leefde voornamelijk van planten en heel misschien af en toe een insect. Zijn nek stond redelijk rechtop. Zo kon hij bij blaadjes die hoger groeiden

De tanden van sauropoden waren aangepast om plantendelen van de takken te trekken en niet om mee te kauwen. Dit was ook zo bij Camarasaurus.

 May 13, 2011  Filed under: Ornithopoda —   The original species of Camptosaurus is based on ten partial skeletons, ranging from juveniles to adults. The species is well-known from the mounted skeletons of a juvenile and an adult collected by Fred Brown and William H. Reed in the 1880s in Wyoming, USA, and put on display in the Smithsonian Institution in Washington DC. The English species is a nomen dubium and may not even be an ornithopod.

ROM camptosaurus
//some people think they were obligate bipeds, thus the warning label on the photo  page on wikimedia . And as mentioned: more research needed.
WARNING   ;   the bipedal gait of the animal is  almost certainly  wrong  
Factbox °
//NameCamptosaurus, meaning ‘flexible lizard’  Size: 7m long and up to 6m tall  Food: plants Lived: 155-140 million years ago, in the Late Jurassic and Early Cretaceous Periods in western Europe and North America
Camptosaurus is very similar to its cousin Iguanodon, a genus which was a characteristic feature of the landscape of the later early Cretaceous period in Europe. However, its head is longer and lower, and it has four toes on the back foot rather than three. Its heavy body can be carried on four legs (or on two, ? )  both its front five-fingered feet and its hind feet carrying weight-bearing hooves. Its long mouth contains hundreds of grinding teeth and it has a beak at the front. Its food would be kept in cheek pouches while chewed.
The curved thigh bone of this dinosaur enabled it to run quite fast on its powerful hind legs. As it ran, Camptosaurus balanced its bulky body with its heavy tail. This peaceful dinosaur had no weapons, such as horns or sharp claws, and the only way it could escape larger carnivorous dinosaurs was to run away. The strong, agile rear legs were made for running. It needed to be able to escape from an Allosaurus that could easily overpower even the largest Camptosaurus. Its front legs were small but strong and were used for slow movement during feeding and grubbing around in the brush. It fed with its short front legs on the ground, and the tall hips and rounded curve of the tail gave Camptosaurus a curved or bent profile. This is how it got its name.
It is possible that the original species of Camptosaurus is the only true one. The others may be species of Iguanodon.
camptosaurus NHM
camptosaurus 001
  • camptosaurus elbow and hands hands and elbow   MHN


Photo Album carcharodontosauridae

Carnotaurus sastrei , is one of the strangest dinosaurs to have come from South America. It was discovered in Patagonia, the southern tip of Argentina.
The most unusual feature of this meat-eating dinosaur was that it had two short, knobby eyebrow-horns and a small, deep shaped skull, making it look somewhat like a bull. These characteristics are reflected in its name. The horns were probably used more to impress females than for fighting.
Carnotaurus was fierce looking fellow. Its eyes faced forward, which is unusual in a dinosaur, and may indicate binocular vision and depth perception. It could look you in the eye, then flash a mouthful of flesh-tearing teeth, which enough to scare the pajamas off anything.
. Although the upper part of the skull seems powerful, the lower part appears slender and weak. The snout is incredibly blunt and deep, giving Carnotaurus the appearance of a dinosaur bulldog. Perhaps the strangest feature of this theropod is its tiny, underdeveloped arms, probably the tiniest of any of the larger meat-eaters. Its arms were so short that the hands appeared to sprout almost directly from the elbows. The forearms were not much longer than the fingers and they did not bend. It had primitive four-fingered hands and one of the fingers was a backward-facing spike. The palms faced outwards.
Carnotaurus sastrei was discovered in province of the Chubut by doctor A’ngel Tailor, who noticed a concretion of bone fragments. It was excavated in 1984 by José F. Bonaparte, who led a paleontological expedition of the Argentine Museum of Natural Sciences. it seemed that it was impossible to extract that material because it was on a tremendously hard rock, but eventually a single nearly complete skeleton has been described including impressions of skin along almost the entire right side.
Carnotaurus provided the best theropod skin impressions ever found. The skin was leather-like and lined with rows of bumps, that become larger toward the spine. These small cone-shaped nodules, each about two inches (5 cm) across, were regularly spaced over its body. Bonaparte says that when dying, this animal had been thrown on the mud, that when becoming hardened perfectly copied the texture of the leather. Although closely related to the feathered dinosaurs, the highly-detailed skin impressions showed no sign of feathers.

by Scot Hartman


(click on the  drawing   )
This is Carnotaurus sastrei, a theropod that seems to be little more than a mouth with a set of legs to carry it around. Carnotaurus belongs to an aberrant group of theropods called abelisaurs, which dominated much of the southern hemisphere during the Cretaceous. While all abelisaurs appear odd to our tetanuran-biased eyes, it seems like Carnotaurus is striving for weirdness as a means to its own end; as if it were making some sort of meta-commentary on abelisaur diversity.
The hyoid bones –
 the bones that support several muscles, including in dinosaurs the tongue musculature. Being long, slender bones that don’t directly articulate to other bones, hyoids are often not found (and other times are probably not collected or m-identified). Even when they are found, their lack of a direct connection to other bones makes restoring them problematic. In Carnotaurus this wasn’t a problem, as they were found in direct association with the underside of the mandible, apparently in their life position. The fact that extensive skin impressions were found with Carnotaurus reinforces the likelihood that the soft tissue holding the hyoid in place had not been disturbed.
In the skeletal above you can see part of the hyoid sticking out from under the bottom-rear part of the jaw. Part of the hyoid is obscured, but there’s not much I can do about that. Having the hyoid is actually pretty useful – the trachea and esophagus have to pass through it (or above it), so having a properly positioned hyoid constrains the throat tissue.
Carnotaurus is also striking due to its advanced arm reduction – in side view the arms almost disappear, as they don’t even extend past the stomach. What on Earth could such arms be used for? Hold on to that thought, as I’m not ready to go public with my thoughts on that just yet. But it sure reinforces the “legs carrying a head” image.
The back and neck also have osteological structures that raise up to, or above the level of the neural spine. So most of the animal should be restored as having a remarkably flat top. Given how narrow the head is, this must have produced a really strange life appearance.
A final note on the skeletal itself: while Carnotaurus is a wonderfully complete specimen, the lower legs and much of the tail is missing, so those elements were restored after its close cousinAucasaurus.
Carnotaurus January 25, 2012  Filed under: Theropoda —

This large predatory dinosaur had a thick, powerful neck, a bull-shaped head and very short forearms for its size.

Carnotaurus was previously considered to be a member of the group of dinosaurs known as the carnosaurs. However, the group has since been defined to encompass only the allosaurs and their closest kin. It is now classified as an abelisaurid. Carnotaurus had a shorter and deeper skull than Tyrannosaurus and had hornlets over its eyes.

An almost complete skeleton of Carnotaurus was extracted with difficulty from the hard mineral nodule in which it was preserved in Argentina. The deep skull suggests that it may have had an acute sense of smell, but the strength of the jaws and neck implied by the muscle attachments seem at odds with the weakness of the lower jaw and teeth.

Factbox  //Name: Carnotaurus, meaning ‘meat-eating bull’  Size: 7.5m long and 3.5m high Food: meat, mainly other dinosaurs Lived: 100-90 million years ago in the Middle to Late Cretaceous in South America

The head is very short and squashed-looking, with a shallow, hooked lower jaw. Two horns stick out sideways from above the eyes, probably being used for sparring with rivals. The arms are extremely short with no apparent forearms, even shorter than the tiny arms ofTyrannosaurus. They form mere stumps with four miniscule fingers. The skin texture, the best-known of any theropod, has a groundmass of small, pebbly scales but with large, conical scutes forming rows along the sides.

The skull of Carnotaurus has an enormous hole in front of the eye sockets – this is known as the antorbital fossa. All theropods possess this, but only in the abelisaurids is it so large

Its long, muscular hind legs may have made Carnotaurus much more agile than some other theropods. It would have been able to rush up on its prey and take it by surprise, probably using its sharp claws to slash and grip, while its powerful jaws took out chunks of flesh.

Although Carnotaurus had a very strong skull, it also needed to be light enough to move easily. There were spaces in the sides of the skull to help make it lighter. By jerking its head back, Carnotaurus could tear its prey apart. The teeth in the upper jaw could slice through the flesh, which was held by the lower jaw. Carnotaurus had teeth about 4cm long which curved backwards to help it keep hold of its victim.

Carnotaurus was found in a vast area of grassland and semi-desert called Patagonia in Argentina in 1985. It was an exciting find because the remains gave scientists a very good idea of what this dinosaur’s skin looked like. Along the surface of the body, from head to tail, there were rows of cone-shaped bumps. Rows of big, raised sclaes stood out from the smaller bumps on Carnotaurus’ head, making a pattern around the eyes and on the upper part of its snout.

Carnotaurus was as heavy as a car, almost as tall as an elephant and ran on two legs. Its long backbone was like a big girder supporting the weight beneath. Long rib bones from shoulder to hip gave Carnotaurus extra protection and support.

When Carnotaurus was moving at top speed it would have been unstable without its tail. Carnotaurus used its long, muscular tail to help it keep its balance. This enabled it to push its head forward to seize hold of its struggling prey.

At the top of its short deep head, Carnotaurus had a pair of small, flat horns. These jutted forward over its eyes rather like little wings. Unlike the ceratopsians, such as TriceratopsCarnotaurus’ horns were too small to have been used for defence. Experts think that they may have been coated in extra layers of horn, which would have made them longer. Like stag deer, it is also possible that the male Carnotaurus had larger horns than the females.

Centrosaurus nasicornis

Gehoornde hagedis
Afbeelding Centrosaurus nasicornis

: Krijt: Ornitischia: Herbivoor: 6m

Deze planteneter hoort bij de Ceratopsia (‘gehoornde dinosauriërs’), net als zijn verwanten Chasmosaurus en Triceratops. En dat kan je goed zien: deze dino heeft een kort nekschild, twee kleine hoorns boven de ogen en één grote hoorn op de snuit. Hij heeft ook een scherpe papegaaienbek, waarmee hij planten kon afknippen. Hij liep dus rond met een schaar op zijn snoet.

Deze dino leefde 75 miljoen jaar geleden. Paleontologen vonden hem in Noord-Amerika.



this rather lovely centrosaurus skeleton. nearly complete from head to toe…  it had toe bones. this skeleton apart from some vertebrae was complete

Another lovely centrosaurus… (or if you’re into brown’s interpretation =  the type specimen of monoclonius nasicornis.).. skeleton. Again nearly complete head to tail.



  Figure 10.Ceratopsia.
(a) Skulls of Psittacosaurus and (bProtoceratops.

A protoceratops flock.

Protoceratops skull growth series.
From left: Small Juvenile, Large Juvenile, Small Adult, Large Adult.

A Psittacosaurus flock

List of ceratopsian genera by classification and location follows a review by Thomas R. Holtz, Jr. in 2010.


Ceratosaurus     Ceratosaurus         


Plusieurs squelettes de Ceratosaurus adultes ont été retrouvés à ce jour. C’est le plus grand et d’une certaine manière le plus primitif des cératosaures. Il a de nombreux points communs avec Allosaurus. Cependant, il montre plusieurs différences subtiles. En particulier, sa main possède quatre doigts développés, à la différence d’Allosaurus qui n’en a que trois. En comparaison, Cératosaurus semble avoir été plus agile.

Ceratosaurus “Lézard cornu ” possédait trois orteils munis de griffes.

Selon les espèces, la taille est estimée entre 5,7 et 6 m.

Ceratosaurus vivait en Amérique du Nord, en Europe et en Afrique. Les fossiles ont été retrouvés dans le Colorado et le Wyoming. D’autres fossiles ont été découverts au Portugal et en Tanzanie.

Les fossiles sont tous datés du Jurassique supérieur.

Il portait une petite corne sur le museau, juste derrière les narines. Cette corne était trop fine pour servir d’arme. On ne connaît pas exactement la fonction de cette corne. Peut-être servait-elle à la parade amoureuse ?

Ses mâchoires imposantes avaient des dents incurvées et acérées

La rangée de plaques osseuses, qui forme une crête dentelée le long de son dos, aurait pu servir à réguler sa température.

Il portait également une petite crête devant chaque oeil.

Les empreintes, trouvées dans les roches de la Formation Morrison, dans l’ouest des Etats-Unis, montrent que ces dinosaures se déplaçaient en groupe. Ils pouvaient peut-être s’associer pour chasser ou pourquoi pas avoir une organisation “sociale”.

Classification: Saurischia Theropoda Ceratosauria        Plusieurs espèces ont été décrites:

Ceratosaurus nasicornis
Ceratosaurus ingens
Ceratosaurus magnicornis
Ceratosaurus roechlingi
Ceratosaurus willisobrienorum

The Largest Ceratosaurus

Eastern Utah’s Cleveland-Lloyd dinosaur quarry is a treasure trove of predatory dinosaurs. In addition to elements from more than 46 individual Allosaurus, this fossil-rich pocket has yielded remains of rarer predators that lived in the region 150 million years ago, including the little-known Marshosaurus and the tyrannosaur Stokesosaurus.
The charismatic, well-ornamented predator Ceratosaurus has been uncovered from these deposits, too, but the particular individual found in the Jurassic quarry might belong to a species that was only recently recognized.
Since the late 19th century, the Ceratosaurus genus has been best represented by one species: Ceratosaurus nasicornis.
Paleontologist O.C. Marsh included a beautiful reconstruction of this dinosaur in a kangaroo-like pose in his essential 1896 tome The Dinosaurs of North America. In 2000, however, paleontologists James Madsen and Samuel Welles named two additional species in their detailed monograph on the osteology of Ceratosaurus.
One, represented by an articulated skeleton found in Colorado’s Fruita Paleontological Area, was named Ceratosaurus magnicornis,
and the unusual Cleveland-Lloyd specimen was dubbed Ceratosaurus dentisulcatus.

The Cleveland-Lloyd species was not found all together in a single, articulated skeleton. Work over many years turned up the scattered remains of what Madsen and Welles considered to be a singleCeratosaurus individual.
When the isolated parts were viewed together, the paleontologists were struck by the size of the dinosaur. This Ceratosaurus was significantly larger than any found before. (I have seen these fossils myself in the Natural History Museum of Utah collections, and compared to the skeleton on display at the Smithsonian National Museum of Natural History, the Cleveland-Lloyd Ceratosaurus is huge.) What Masen and Welles called Ceratosaurus dentisulcatus also differed in various anatomical aspects such as larger, more recurved teeth and a nasal opening set lower down at the front of the skull. Sadly, the portions of the skull which preserved the dinosaur’s ornaments were not found, so we don’t know how this species might have differed from others in this respect.
It’s difficult to say how large this individual actually was. The Cleveland-Lloyd Ceratosaurus was much larger than the roughly 17.5-foot specimen that formed the basis of previous anatomical descriptions, and informal estimates have placed the larger species at about 28 feet. Yet, given the new interest in dinosaur growth, I have to wonder if Ceratosaurus dentisulcatus really represents a bigger, badder species than Ceratosaurus nasicornisCeratosaurus is a relatively rare dinosaur, so much so that we still don’t have a good idea of how individuals varied from one to another, nor do we have a solid understanding of Ceratosaurus growth. Maybe the Cleveland-Lloyd Ceratosaurus is just an older, and therefore larger, individual of Ceratosaurus nasicornis in the same way that the dinosaur often called Saurophaganax might be an older or particularly large variant of Allosaurus. Even though the dinosaurs of the Morrison Formation have been known for a long time and seem familiar, there is much we still don’t know about their biology.
References:   Madsen JH, Welles SP. Ceratosaurus (Dinosauria, Therapoda), a Revised Osteology. Miscellaneous Publication. Utah Geological Survey.                                                          Brian Switek

Especes dinosaures

V.B (05.2003) M.à.J 30.01.2006

Picc © Joe Tucciarone and Jeff Poling

Ceratosaurus / meaning ‘horned lizard’, in reference to the horn on its nose (Greek keras/keratos meaning ‘horn’ and sauros meaning ‘lizard’), was a large predatory dinosaur from the Late Jurassic Period, found in the Morrison Formation of North America, in Tanzania and possibly in Portugal. It was characterized by large jaws with enormous, bladelike teeth, a large, blade-like horn on the snout and a pair hornlets over the eyes. The forelimbs were powerfully built but very short. The bones of the sacrum were fused (synsacrum) and the pelvic bones were fused together and to this structure (Sereno 1997) (i.e. similar to modern birds). Evidence suggests that there may also have been a row of small spurs or even a low sail, along the spine.

Discovery and species

Ceratosaurus is known from the Cleveland Lloyd Dinosaur Quarry in central Utah and the Dry Mesa Quarry in Colorado. The type species, described by O. C. Marsh in 1884 and redescribed by Gilmore in 1920, is Ceratosaurus nasicornis. Two further species have recently been described in 2000, C. magnicornis, and dentisulcatus. However, additional species, including C. ingens, C. stechowi and a species that has been referred to as C. meriani, from Portugal, have been described from less complete material. While C. nasicornis remains the type species and is cited at around 6 meters (20 feet) in length, additional finds indicate that this species may be misleadingly small, and that Ceratosaurus was likely larger. Very scant remains of a Ceratosaurus-like theropod have been found in Tanzania and would have belonged to an animal at least 15 meters (50 feet) in length, much larger than Allosaurus.


Ceratosaurus lived alongside dinosaurs such as Allosaurus, Torvosaurus, Apatosaurus, Diplodocus, and Stegosaurus. It may have competed with Allosaurus for prey, though it was smaller at around 6 to 8 meters (20-27 feet) in length, weighing 500 kg up to 1 tonne. Ceratosaurus had a longer, more flexible body, with a tail shaped like a crocodilian. This suggests that it was a better swimmer than the stiffer Allosaurus. A recent study by Bakker confirmed that Ceratosaurs generally hunted aquatic prey, such as fish and crocodiles, although it had potential for feeding on large dinosaurs. The study also suggests that sometimes adults and juveniles ate together. This evidence is, of course, very debatable and Ceratosaurus tooth marks are very common on large, terrestrial dinosaur prey fossils.


Relatives of Ceratosaurus include Elaphrosaurus and the abelisaur Carnotaurus. The classification of Ceratosaurus and its immediate relatives has been under intense debate recently. In the past, Ceratosaurus, the Cretaceous Albelisaurs and the primitive Coelophysoidae were all grouped together and called Ceratosauria, defined as theropods closer to Ceratosaurus than to the lineage of aves. Recent evidence, however, has shown large distinctions between the later, larger and more advanced Ceratosaurs and earlier forms like Coelophysis, leading to the naming of the later theropods as Neoceratosauria and closer to, or perhaps even ancesteral to, Tetanuran carnosaurus like Allosaurus. Many Theropods no longer considered close to Ceratosaurus were once classified as relatives, including Eustreptospondylus and Yangchuanosaurus. While it is likely that they are not Neoceratosaurs these ‘more advanced’ theropods do display a sort of middle ground of primitive characteristics compared to Allosaurs (Eustreptospondylus lacks the Allosaur expanded boot-shaped pubic bone, instead having a rod shaped pubis like Ceratosaurus. Many Sinraptors and Allosaurs have a tendency to grow elaborate and multiple horn rows, very visible in Yangchuanosaurus and prominent in Ceratosaurus). Some of the most modern publishings have even begun listing Ceratosaurus as a basal Tetanurae and closer to Allosaurus than Coelophysis. While considered distant from the lineage of aves among the theropods, Ceratosaurus and its kin were still very bird-like and even had a more ‘advanced-looking tarsus than Allosaurus. As with all dinosaurs, the more fossils found of these animals, the better their evolution and relationships can be understood.

Info Copyright © 2006 Answers Corporation

Ceratosaurus nasicornis was een een theropode dinosauriër uit het Jura.

Ceratosaurus werd in 1884 beschreven door Othniel Charles Marsh. Hij is gevonden in lagen van zo’n 150 miljoen jaar geleden in de Verenigde Staten en Afrika, gebieden die zich toen nog op één continent bevonden.

Ceratosaurus was ongeveer zes m lang en 2.50 m hoog, en had enkele kenmerkende eigenschappen. De meeste theropoden zoals Allosaurus hebben hoorns. De twee boven de ogen waren klein en leken meer op kammetjes, zo ook bij Ceratosaurus: bij hem echter was de hoorn op de neus (althans de middenlijn van de schedel, achter de neusgaten) sterk vergroot, en kon, hoewel vrij plat, met recht een ‘hoorn’ genoemd worden. Er was ook een kleiner hoorntje meer achter op de schedel. Sommige schedels hebben grotere hoorns dan andere. Dit kan twee dingen betekenen: er waren verschillende soorten, of er waren verschillen tussen de seksen. De functie van de hoorns is onduidelijk, misschien werden ze door de mannetjes gebruikt bij gevechten. De hoorn op de neus zou ook een geducht wapen kunnen vormen, waarmee het dier prooien aanviel en zich verdedigde tegen de grotere roofdieren, zoals Allosaurus – maar dat kan alleen maar zo geweest zijn als het onbekende hoornweefsel een scherpe kartelrand vormde, want de bewaard gebleven botkern is vrij stomp.

Op de rug van Ceratosaurus liepen de erg lange doornuitsteeksels als een kam over de ruggengraat. Deze kam, en de hoorn(s), gaven het dier een draakachtig uiterlijk.

Ceratosaurus had vier vingers, terwijl de meeste andere theropoden uit de late Jura er drie hadden. In het vroege Jura en het late Trias kwamen wel meer viervingerige theropoden voor (ook vijfvingerige). Deze primitieve eigenschap toont in samenhang met vele andere kenmerken aan dat Ceratosaurus een theropode was uit één van de twee hoofdvertakkingen van de Theropoda, die zelfs naar deze soort genoemd is: de Ceratosauria; de andere vertakking heet de Tetanurae. De vierde vinger was wel kleiner, en had geen klauw.

In 2000 zijn twee andere soorten beschreven: C. magnicornis en C. dentisulcatus. Het is nog zeer omstreden of het hier inderdaad om aparte soorten gaat. De laatste vorm is ongeveer 60% langer. Daar dinosauriërs typisch nooit ophielden met groeien kan het ook om een groot individu van C. nasicornis gaan. De andere vorm had, zoals de naam reeds aangeeft, een grotere hoorn – maar dat is vermoedelijk een zeer variabel kenmerk. Voor een komische noot zorgde in 1995 Pickering door niet-diagnostische resten C. willisobrienorum te noemen, enkel om een tekenstudio te eren. Volgens de regels staat het een ieder vrij om via een publicatie nieuwe soorten te benoemen. De heer Pickering misbruikt deze vrijheid regelmatig.

Een ander vreemd kenmerk van Ceratosaurus , dat hij met vele theropoden deelde, was dat de onvergroeide onderkaken (iedere gewervelde heeft er twee) van de toch al relatief grote (1 m) schedel in het midden (dus aan beide zijkanten van de schedel) gewrichten hadden en ook ten opzichte van elkaar vrij mobiel waren. Dit kan op verschillende manieren geïnterpreteerd worden: allereerst als een vermogen om, net als veel slangen, zijn bek aan de voorkant ‘uit te rekken’. Zo kon het dier vrij grote prooien (bijvoorbeeld de snelle Dryosaurus) in hun geheel doorslikken, als de beide onderkaken van voren uit elkaar klapten. Misschien was dit vanwege de concurrentie van andere roofdieren. Als Ceratosaurus net zoals veel andere dieren gewoon happen uit zijn prooi zou nemen, zou hij niet de tijd hebben om zijn prooi op te eten voordat er aaseters kwamen. Als hij de prooi in zijn geheel kon doorslikken, had hij het volledige maal al op voordat de aaseters de geur konden ruiken. De meer traditionele interpretatie is dat de onderkaaksmiddengewrichten niet naar binnen klapten zodat de punten van voren uit elkaar gingen, maar naar buiten zodat de hele bek korter en breder werd. Dit verhoogt de zaagwerking van de tanden. Voor deze gebruikelijke opvatting pleit het feit dat bij fossielen de onderkaken toch vaak als één geheel bewaard zijn gebleven – wat duidt op vrij strakke kapselverbindingen – en het simpele gegeven dat de normale kaakgewrichten al toestonden de bek enorm open te sperren, terwijl de ingang door de verbreding ook vergroot werd. Ertegen pleit dat mogelijkheid tot de noodzakelijke horizontale beweging van de normale kaakgewrichten nooit aangetoond is.

1. Chilantaisaurus? sibiricus
There are a lot of fragmentary taxa known from a tooth or a vertebra that are poorly described (usually in a useless archaic way) and illustrated in a photo from a single view. What makes sibiricus stand out is that Riabinin (1914) didn’t even identify which element the holotype was, let alone try to describe its features. He just said it was hollow and belonged to the limb of a fairly large theropod, probably a megalosaurid (named as Allosaurus? sibiricus). Even worse, he didn’t illustrate it, only providing six measurements (proximal width 48 mm, proximal depth 39 mm, distal width 68 mm, distal depth 62 mm, cavity width 22 mm, cavity depth 17 mm). Huene (1932) identified it as a distal metatarsal IV without rationale, but said only that it did not permit exact characterization and probably belonged to an allosaurid (renamed Antrodemus? sibiricus). Molnar et al. (1990) then said it was “almost identical with that of C. tashuikouensis in form and proportions of the distal condyle”, so questionably referred it to that genus. You now possess the entirity of published information on sibiricus.

Artist’s restoration of Ceratosaurus.


 June 19, 2011

Filed under: Theropoda —
Coelurus would eat anything it came across – even the rotting carcasses of animals killed by other dinosaurs.
It was a nippy little dinosaur, with a small head about the same size as a man’s hand. Its teeth were razor-sharp and curved. Once they had sunk into another animal, it was almost impossible for the prey to wrench itself free. Coelurus also used its powerful teeth and jaws to rip flesh from the rotting carcasses of prey killed by other carnivores.
For a long time Coelurus was thought to have been another specimen of Ornitholestes. However, studies by John Ostrom in 1976 and Jacques Gauthier in 1986 show that the hands are like those of the maniraptorans. In contrast, the neck is nothing like that of a maniraptoran and it is unclear whether this animal fits into the dinosaur family tree.

Name: Coelurus, meaning ‘hollow tail’
Size: 2m long
Food: meat, usually dead dinosaurs it found
Lived: about 140 million years ago during the Late Jurassic Period in North America
This animal is another of the small, hunting dinosaurs. It has a strangely down-curved jaw with sharp, curved teeth. The hands are long but not particularly strong, with a wrist joint similar to that of a bird, and very flexible fingers. The ‘hollow tail’ part of the name refers to the deep excavations in the vertebrae of the back and tail, something like those found as a weight-saving measure in sauropods.
Coelurus had very light bones and a stiff tail with hollow bones in it. Its front limbs were short and slim. Its hands were small and weak, with three curved claws. Coelurus had similar, slightly blunter claws on the toes of both back limbs. It used its hands to snatch at its prey and to keep it in its grasp, while ripping it to death with the claws on its feet.
Specimens of Coelurus found in four locations in the same quarry may have come from the one individual. That individual may not even have been fully grown, and so the size estimate here may be on the small side.


Signification : A queue creuse

Taille : 2 mètres de long

Poids : 15 à 30 kilogrammes

Groupe : Théropodes

Famille : Coeluridés

Epoque : Jurassique supérieur (156-137 ma)

Régime alimentaire : Carnivore

Répartition : Etats-Unis (Wyoming)

Coelurus possédait une petite tête (20 cm). Ses os creux rappellent ceux des oiseaux. Il devait sûrement se nourrir de petits lézards et de petits mammifères ou encore d’insectes. Ses proies étaient limitées, étant donné sa petite taille, même si les insectes et les petits lézards proliféraient avec le climat radieux des forêts et des marécages de l’Amérique du Nord du Jurassique supérieur. Même si tenté par les charognes de dinosaures comme Camptosaurus qui gisaient près des rivièresfaute d’eau; ils ne pouvaient que rester regarder. Car leurs dents étaient trop petites pour transpercer la peau des gros dinosaures. Ainsi, Coelurus était un petit prédateur insectivore et qui se nourrissait aussi de petits mammifères et de petits lézards. Ses mains, pourvues de trois doigts griffus, étaient longues et puissantes, permettant d’arracher la chair de ses petites proies. 

Klik hier om een link te hebben waarmee u dit artikel later terug kunt lezen.<– De Bultenaar uit spanje

De Concavenator corcovatus.( “gebochelde vleeseter van Cuenca”)… Het vier meter lange   roofdiier  leefde -132 MY geleden

Francisco Ortega  van de universiteit van  Madrid      http://dfmf.uned.es/biologia/personal/fortega/
, vond   de dino-beenderen in de Los Hoyas vlaktes van centraal Spanje.
Destijds was dat een moerasgebied dat nu vergelijkbaar is met de Everglades.  De  koosnaam van het  fossiel werd  “Quasimodo  van  Las Hoyas ”

De vondst is het  tot nu toe meest volledige fossiel  van  met    haaientanden   uitgeruste drietenige theropoden, genoemd : de  carcharodontosauria theropoden,…..” waren een erg bijzondere groep dinosauriërs, omdat vogels tot dezelfde groep behoren”,
verklaart onderzoeker Jose Franz op BBC News.

“De wereld zou niet hetzelfde zijn zonder vogels. Vogels zijn eigenlijk een soort gevleugelde theropoden.”

Het opgegraven dier heeft twee verlengde ruggenwervels, waardoor een soort bochel is ontstaan.
De onderzoekers denken dat  deze theropode  een bescheiden driehoekige kam op zijn rug had, , maar zo’n kam is bij verwante dinosaurussen nooit gevonden. Spinosaurus gebruikten rugkammen misschien om te pronken of om af te koelen, maar hun kammen bedekten een veel groter deel van de ruggegraat.

“Eén van de meest in het oog springende karakteristieken van de Concavenator is de bijzondere verlenging van de laatste twee ruggenwervels”,
verklaart hoofdonderzoeker Ortega.
“Dit is nog niet eerder vertoond bij dinosauriës die tot nu toe zijn opgegraven. De functie van de bochel is onbekend.”

Opvallend aan het beest is niet alleen de merkwaardige bultkam op zijn rug, maar ook het feit dat hij aan zijn voorpoten aanhangsels moet hebben gehad diemogelijk voorlopers waren van veren te vergelijken  met die waarmee kan worden gevlogen.
Maar , hoe ze er precies uitzagen en wat hun functie was, is eveneens ( nog )    onbekend.

Op de reconstructie     (fig2)  heeft de theropode  aan de voorpoten een minimale franje gekregen, maar het zouden ook vertakte veerachtige structuren geweest kunnen zijn, aldus de onderzoekers.

De  bulten /littekens  op de voorarmen van de dino zouden  wel  eens  een aanwijzing kunn en zijn  dat het landdier mogelijk  gevederd    was ..al willen/kunnen  de onderzoekers daar nog geen  verdere speculaties  aan verbinden .

De bobbels zijn mogelijk het oudste bewijs voor de groei van primitieve veren bij dieren, zo melden de onderzoekers in het wetenschappelijk tijdschrift Nature.

“Deze eigenschap is eerder waargenomen bij kleine dinosauriërs die nauwer verwant zijn aan vogels, zoals de Velociraptor”, verklaart hoofdonderzoeker Francesco Ortega op Discovery News.
“Deze dinosaurus is vier keer groter dan de Velociraptor en( =de haaientanden /carcharodontosauria)
werden  tot nu toe beschouwd als te primitief ( in dit opzicht )om veren te hebben.”

“Toch beschikt dit dier ook over deze kleine bobbels waaruit waarschijnlijk primitieve veren groeiden”, aldus Ortega.

.The dinosaur’s unusual skeleton included a hump over the ilium – where the hind legs join the spine – and around five bumps on the forearm…..these bumps( knobs )  have been seen in dinosaurs before – including Velociraptor, it is interesting and new to find this characteristic in a dinosaur that is so far removed from either birds or previous known feathered dinosaurs.The bumps are very similar to those in present-day birds,(= quill knobs ) with just two differences.
There are fewer bumps in the Concavenator and they are not in such a regular arrangement. 
The team interpret these differences in evolutionary terms.
They suggest that over evolutionary time the bumps could have evolved into the feather attachments that are found in modern birds

*The hump found on the dinosaur’s spine is more of a mystery, however. Humps are common in dinosaurs, and can be used for heat regulation – when they might look like a kind of sail – for display, or for food storage.

Scientists and fossil (Ortega/Sanz) The scientists from Madrid uncovered the bones in Cuenca, central Spain

The team cannot work out what this hump might be for, though.

It is probably not for heat regulation, since normally a hump of this type would need an extensive blood supply, and there would be evidence within the surrounding bone – the team did not find this.

Also, most previous dinosaur humps have been found around the shoulders or the centre of the back – this hump is further towards the tail…

The hump
 could  also represent  another
“…..anchors to the ligaments that hold the flight feathers.
Maybe Concavenator wasn’t  ( flight- )feathered,  but its hump could represent an evolutionary step in that direction….”

Concavenator corcovatus : 
A bizarre, humped Carcharodontosauria (Theropoda) from the Lower Cretaceous of Spain

Fernando Escaso  & José L. Sanz    Nature Volume: 467 ,Pages:203–206   Date published:(09 September 2010)

Francisco Ortega,fortega@ccia.uned.es

Figure 1: Holotype of Concavenatorcorcovatus.

Holotype of Concavenator corcovatus.

Specimen MCCM-LH 6666 from the Lower Cretaceous series (Barremian stage) of Las Hoyas (Cuenca, Spain). a, Photograph under visible light. b, Schematic interpretation of the exposed right side of the skeleton. a, astragalus; aofe, antorbital fenestra; co, coracoid; d11–12sp, neural spines of the eleventh and twelfth dorsal vertebrae; fe, femur; fi, fibula; hu, humerus; il, ilium; is, ischium; j, jugal; l, lacrimal; mt III, third metatarsal; mx, maxilla; na, nasal; po, postorbital; pu, pubis; ra, radius; sc, scapula; ti, tibia; u, ungual phalanx; ul, ulna.

Figure 2: Time-calibrated reduced consensus of the phylogeny of Neotetanurae theropods.

Time-calibrated reduced consensus of the phylogeny of Neotetanurae theropods.

a, Hypothetical flesh reconstruction of Concavenator corcovatusb, The phylogeny resulting from a parsimony analysis of the data matrix6 in which Concavenator is incorporated (seeSupplementary Information). If poorly represented carcharodontosaurian taxa are considered, Concavenator is located either as the sister group to the remaining Carcharodontosauria or as a basal carcharodontosaurian, but on removing the less informative taxa, Concavenator stands unequivocally as the most basal Carcharodontosauridae. Concavenator possesses two unambiguous synapomorphies of Carcharodontosauria: a deeply concave iliac articular surface on the ischia and a proximomedially inclined femoral head. Our analysis agrees with recent hypotheses6 in considering that Carcharodontosauria is basally split into Carcharodontosauridae and Neovenatoridae6. Two cranial synapomorphies would place Concavenator within Carcharodontosauridae: the lacrimal-postorbital contact and a large curving flange in the jugal process on the postorbital. Maa, Maastrichtian; Cam, Campanian; San, Santonian; Con, Coniacian; Tur, Turonian; Cen, Cenomanian; Alb, Albian; Apt, Aptian; Bar, Barremian; Hau, Hauterivian; Val, Valanginian; Ber, Berriasian; Tit, Tithonian; Kim, Kimmeridgian; Oxf, Oxfordian; Cal, Callovian; Bat, Bathonian; Baj, Bajocian; Aal, Aalenian

Figure 3: Details of the holotype of Concavenatorcorcovatus.

Details of the holotype of Concavenator corcovatus.

Specimen MCCM-LH 6666 from the Lower Cretaceous series (Barremian stage) of Las Hoyas (Cuenca, Spain). a, Lateral view of the skull. b, Middle part of the axial skeleton showing the distribution of the height of the neural spines of vertebrae around the pelvic region. c, Detail of distal phalanx of the right foot showing impressions of plantar pads and corneous sheaths of the ungual bones. d, Impressions of hexagonal scales associated with the fifth metatarsal. e, Distal portion of the tail vertebrae showing a body outline. f, Distal portion of the tail vertebrae showing a body outline and the disposition of some rectangular scales. il, ilium; ip, intraorbital process; ob, orbital brow; mt V, fifth metatarsal; sp10–12, neural spines of the tenth–twelfth dorsal vertebrae.

Figure 4: Forearm of Concavenatorcorcovatus.

Forearm of Concavenator corcovatus.

Specimen MCCM-LH 6666 from the Lower Cretaceous series (Barremian stage) of Las Hoyas in Cuenca, Spain. a, Forearm (radius and ulna) of Concavenator corcovatusb, Detail of the posterolateral crest showing a series of feather quill knobs (arrows mark the available five elements of the series). c, Dorsal view of the ulna of an extant turkey vulture (Cathartes sp.). Scale bars, 1cm.

Five bumps were found on the fossil arm bones (top) whereas modern birds such as the turkey vulture (bottom) have eight to 10.



 New dinosaur extinction theory, a new dinosaur and more

(10 m)
3.5 tons (3,200 kilos)
Late Cretaceous – 75 MYA
Alberta, Canada; Montana, USA

Corythosaurus is a member of the planting-eating, duck-billed dinosaur family that is sometimes referred to as hadrosaurs. It had a toothless, wide beak and hundreds of teeth in the back part of its mouth that it used for grinding tough plants to mush. Like other duckbills, it was a herd animal that traveled in large groups. Fossils of this dinosaur are sometimes found together with other plant-eating dinosaurs, which leads scientists to believe that different types of plant-eaters grouped together to feed, drink and maybe even migrate (moving from one area to another).
Corythosaurus is most famous for its helmet or half dinner plate-like crest. It is known from remains belonging to at least twenty individuals. The crest is similar to the helmets worn by ancient Corinthian warriors; this resulted in its name. The crest grew until adulthood and was likely used as a mating ritual ornament. There appears to be gender differentiation regarding the size of the crest, with males having a larger crest. At least 10 skulls have been identified from this species, giving scientists a good look at individual and gender differentiation. Fossilized skin remains have also been found, further contributing to the knowledge of Corythosaurus.

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Ceratopsidae Ceratopsians

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