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09.01.2016 18:11 - Encyclopedia Largest prehistoric animals Vol.1 Vertebrates part3 Dinosaurs ch.2 Sauropods-Titanosaurids,other main contenders for the title at heavyweight
Автор: valentint Категория: Забавление   
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Paralititan (meaning "tidal giant" was a giant titanosauriansauropoddinosaurgenus discovered in coastal deposits in the Upper CretaceousBahariya Formation of Egypt. It lived between 98 and 93 million years ago. It was called by one science journalist "what appears to have been the second largest known creature ever to walk on Earth."

Joshua Smith and his fellow discoverers called it Paralititan stromeri which means "Stromer"s tidal (Greek para + halos "near sea") titan" or "Stromer"s tidal giant".
The fossil represents the first tetrapod reported from the Bahariya Formation since 1935. Its 1.69 meter (5.54 ft) long humerus is longer than that of any known Cretaceous sauropod.
Smith, who led the research team that found the dinosaur fossils, told an interviewer, "It was a truly enormous dinosaur by any reckoning."
Little of Paralititan is known, so its exact size is difficult to estimate. However, the limited material suggests that it is one of the most massive dinosaurs ever discovered, with an estimated weight of 59 tonnes (65 short tons). Using Saltasaurus as a guide, Carpenter estimated its length at around 26 meters (85 ft). Like other titanosaurs, it had a wide-gauge stance and may have possessed osteoderms for defense. The Paralititan type specimen appears to have been scavenged by a meat-eater. It is also possible that Paralititan was hunted by large predatory dinosaurs such as, Bahariasaurus, Carcharodontosaurus, and Spinosaurus, though this would only be possible if the mentioned predators were able to hunt in groups of at least several individuals.
The autochthonous, scavenged skeleton was preserved in tidal flat deposits containing fossil mangrove vegetation. The mangrove ecosystem it inhabited was situated along the southern shore of the Tethys Sea. Paralititan is the first dinosaur demonstrated to have inhabited a mangrove biome. It lived at approximately the same time as giant predators Carcharodontosaurus, Spinosaurus, and the sauropod Aegyptosaurus.
It was a ground-dwelling herbivore.

Not many fossilised bones of this dinosaur are known, but those that are are simply huge. Comparing these bones to the more complete remains of other genera has resulted in very rough estimates of around thirty meters long, raising the probability that Ruyangosaurus was one of the largest animals to ever walk the Earth. The only way that a more accurate figure for Ruyangosaurus could ever be established is if a single the missing parts are found, and unfortunately this is not likely. The bigger an animal is, the longer it takes for it to become buried so that the remains are protected from scavengers and the elements so that the bones can fossilise. This is why
sauropod dinosaurs are usually found piecemeal, though several partial individuals of a genus can be just as good if not better than a single individual as this would enable the establishment of an average size for a species and not just one individual.
It seems that Ruyangosaurus is not the only large sauropod from the early Cretaceous of China, with Huanghetitan and Daxiatitan both also hinted at being some of the largest known sauropods.

Huanghetitan (meaning "Yellow River titan"), is a genus of sauropoddinosaur from the early Cretaceous Period. It was a basal titanosauriform which lived in what is now Gansu, China.

The type species, Huanghetitan liujiaxiaensis, was described by You et al. in 2006. It is known from fragmentary materials including two caudal vertebrae, an almost complete sacrum, rib fragments, and the left shoulder girdle, and was discovered in the eastern part of the Lanzhou Basin (Hekou group) in the Gansu Province in 2004.
A second species, "H." ruyangensis, was described in 2007 from the Mangchuan Formation of Ruyang County, China (Henan Province). A recent cladistic analysis has found that this species is not related to H. liujiaxiaensis and requires a new genus name. It is known from a partial vertebral column and several ribs, the size of which (the largest approaches 3 m (10 ft)) indicate it had among the deepest body cavities of any known dinosaur. This second species, along with its local relatives Daxiatitan and Ruyangosaurus, is one of the biggest dinosaurs ever found in Asia, and possibly one of the largest in the world.

Since it was named in 1989, the dinosaur genus Bruhathkayosaurus  has attained almost mythical status. The original description of the bones of this dinosaur were originally interpreted as belonging to a theropod dinosaur, though later study of the description has led readers to conclude that the remains were actually of a titanosaurid sauropod, and an impressively large one at that. Apparently the tibia of Bruhathkayosaurus was two meters long, forty-five centimetres longer than the tibia of Argentinosaurus which is confirmed as one of the largest dinosaurs ever. However there is one major problem with the fossils of Bruhathkayosaurus: they no longer exist.

There are reports that not long after the discovery of the Bruhathkayosaurus fossils, the fossils were swept away and lost in a monsoon. On top of this, no diagnostic characteristics were identified or described in the original description. The only representation for what the original fossils look like is in the form of line drawings that were made of them. What this leaves us with is a claim for one of the largest dinosaurs ever that cannot in anyway be substantiated, making Bruhathkayosaurus one of the most dubious of all the dubious genera of dinosaurs.
This is not actually the first time that what might have been the biggest dinosaur ever has had fossils that disappeared. In 1878 the famous American palaeontologist Edward Drinker Cope named Amphicoelias based upon the description of unusually large vertebrae and limbs that bore a resemblance to the fossils of Diplodocus, but greater in scale. Somehow, and at the time of writing no one knows how, these massive fossils have been lost, leaving only detailed drawings and a written description of the bones. Many still question the validity of Amphicoelias, with some suggesting that Cope may have incorrectly measured the fossils, to other theories. But in Amphicoelias there is at least a more detailed description that might allow for new fossils to be attributed to the genus. The loss can also be explained as some kind of storage error as a result to of the huge number of fossils that Cope was dealing with. Remember that Cope was one of the two main figures of the ‘Bone Wars’ and fossils were collected and stored in such great amounts that palaeontologists are still sifting through and cataloguing some of this fossils today, almost one hundred and fifty years after they were collected.
Back to Bruhathkayosaurus and things are far more uncertain. It is not unknown for fossils to be lost and destroyed by environmental factors before they can be discovered, but when fossils that are supposed to represent one of the most ground breaking dinosaur discoveries ever made, it causes many to question if they ever actually existed. There has at least been some speculation that incredibly long shin bones of Bruhathkayosaurus may have actually been the fossilised remnants of tree trunks. Because only line drawings of the original fossils remain, estimates for the size of Bruhathkayosaurus can vary wildly, ranging anything from thirty up to forty-five meters long, or even longer. Thirty to thirty-five meters long would certainly be plausible given that we know of other sauropods of various that that could reach that, such as Argentinosaurus, Supersaurus and Diplodocus. Beyond this though and fossils are certainly required before other people will believe how big something was.

Turiasaurus (meaning "Turia lizard"; Turia is the Latin name of Teruel) is a genus of sauropoddinosaurs. It is known from a single fossil specimen representing the species T. riodevensis, found in a Spanish rock formation dated to the Jurassic-Cretaceous boundary, around 140 million years old.

Turiasaurus is believed to be the largest dinosaur ever found in Europe, and is among the largest dinosaurs known, at 36–39 metres in length and with a weight of 40 to 48 tonnes the combined weight of six or seven adult male elephants. More recent estimates through scaling of the bones suggest a length closer to 19.8–21 m (65–69 ft) in length and a mass of 30 tonnes, around the same size as other large sauropods of the time such as Lusotitan. The length of its skull is 70 centimetres, which is not too large. According to the paleontologistLuis Alcalб, this is because a larger head might have caused Turiasaurus to break its neck.
Phylogenetic analysis shows that Turiasaurus lies outside of the Neosauropoda division and belongs to a new clade, Turiasauria, together with Losillasaurus and Galveosaurus.
Fragmentary remains of this animal, including an articulated left forelimb (holotype), skull fragments, teeth, vertebrae and ribs, have been found in terrestrial deposits of the Villar del Arzobispo Formation of Riodeva (Teruel Province, Eastern Spain), and a forelimb from Portugal. The fossils were once known informally as "Riodevasaurus", a nomen nudum.The type species, Turiasaurus riodevensis, was formally described by Royo-Torres, Cobos & Alcala, in 2006. In the early 2010s, excavations were made east of Madrid that uncovered the most complete fossil of such creatures in the whole world.

( meaning "Ojo Alamo lizard") is a genus of titanosauriansauropoddinosaurs, containing a single known species, Alamosaurus sanjuanensis, from the late CretaceousPeriod of what is now southern North America. Isolated vertebrae and limb bones indicate that it reached sizes comparable to Argentinosaurus and Puertasaurus, which would make it the largest dinosaur known from North America. Its fossils have been recovered from a variety of rock formations spanning the Maastrichtian age of the late Cretaceous period. Specimens of a juvenile Alamosaurus sanjuanensis have been recovered from only a few meters below the Cretaceous-Paleogene boundary in Texas, making it among the last surviving non-avian dinosaur species.

Alamosaurus was a gigantic quadrupedalherbivore with a long neck and tail and relatively long limbs. Its body was at least partly covered in bony armor. Though most of the complete remains come from juvenile or small adult specimens, three fragmentary specimens, SMP VP−1625, SMP VP−1850 and SMP VP−2104, suggest that adult Alamosaurus could have grown to enormous sizes comparable to the largest known dinosaurs like Argentinosaurus, which has been estimated to weigh 73 tonnes (72 long tons; 80 short tons). The total estimate length of Alamosaurus is estimated at 30 m (98 ft) long.
Though no skull has ever been found, rod-shaped teeth have been found with Alamosaurus skeletons and probably belonged to this dinosaur. The vertebrae from the middle part of its tail had elongated centra. Alamosaurus had vertebral lateral fossae that resembled shallow depressions. Fossae that similarly resemble shallow depressions are known from Saltasaurus, Malawisaurus, Aeolosaurus, and Gondwanatitan. Venenosaurus also had depression-like fossae, but its "depressions" penetrated deeper into the vertebrae, were divided into two chambers, and extend farther into the vertebral columns. Alamosaurus had more robust radii than Venenosaurus.


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Автор: valentint
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