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Dinosaurs

Creatures from another age

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  1. Masiakasaurus by Moondawg

    Masiakasaurus
    Masiakasaurus was a small predatory (theropod) dinosaur from Madagascar, named in 2001. Unlike most theropods, the front teeth of Masiakasaurus projected forward instead of straight down. This unique dentition suggests that Masiakasaurus had a specialized diet, perhaps including fish and other small prey. Other bones of the skeleton indicate that Masiaksaurus was bipedal, with much shorter forelimbs than hindlimbs. Masiakasaurus had an estimated adult body length of around 2 meters (about 6-7 feet).
     
    Masiakasaurus lived around 70 million years ago, along with animals such as Majungasaurus, Rapetosaurus, and Rahonavis. Masiakasaurus was closely related to the noasaurs, small predatory dinosaurs found in South America.
     
    In Malagasy, masiaka means "vicious"; thus, the genus name means "vicious lizard". The type species, Masiakasaurus knopfleri, was named after the musician Mark Knopfler of Dire Straits fame, "whose music inspired expedition crews".

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  2. Baurusuchus by Moondawg

    Baurusuchus is an extinct genus of baurusuchid mesoeucrocodylian from the Late Cretaceous of South America.

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  3. Simosuchus Clarki by Moondawg

    Simosuchus clarki
    Simosuchus clarki ("Clark's Pug-nosed Crocodile") was a small crocodylomorph from the Early Cretaceous of Madagascar. It is named so for its unusually short skull. Fully grown individuals would have been about 1 meter in length.
     
    S. clarki's teeth were shaped like cloves, or maple leaves, and, coupled with the proposterously short snout, were unsuitable for shearing or rending flesh. In fact, these features lead paleontologists to suspect that it was a (largely) terrestrial herbivore.

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  4. Yimenosaurus by Moondawg

    Yimenosaurus
    Yimenosaurus is a genus of prosauropod dinosaur from the Early Jurassic. Fossils from several individuals were recovered from Yimen, China, and the type species Y. youngi was named by Bai, Yang & Wang in 1990. Reconstructions are based on mostly complete skeletons, missing only parts of the limbs.

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  5. Dilophosaurus by Moondawg

    Dilophosaurus
    Dilophosaurus was a theropod dinosaur from the Early Jurassic Period. The name is pronounced ("dy-LOH-fo-sawr-us") meaning 'two-crested lizard', because it had two crests (Greek di meaning 'two', lophos meaning 'crest' and sauros meaning 'lizard')
     
    Dilophosaurus measured around six meters (20 ft) long and may have weighed half a ton.
     
    The most distinctive characteristic of Dilophosaurus is the pair of rounded crests on its skull, possibly used for display. Studies by Robert Gay show no indication that sexual dimorphism was present in the skeleton of Dilophosaurus, but says nothing about crest variation. The teeth of Dilophosaurus are long, but have a fairly small base and expand basally. Another skull feature was a notch behind the first row of teeth, giving Dilophosaurus an almost crocodile-like appearance, similar to the putatively piscivorous spinosaurid dinosaurs. This "notch" existed by virtue of a weak connection between the premaxillary and maxillary bones of the skull. This conformation led to the early hypothesis that Dilophosaurus scavenged off dead carcasses, with the front teeth being too weak to bring down and hold large prey.
     
    The first Dilophosaurus specimens were discovered by Sam Welles in the summer of 1942. The specimen was brought back to Berkeley for cleaning and mounting, where it was given the name Megalosaurus wetherilli. Returning to the same formation a decade later to determine from which time period the bones dated, Welles found a new specimen not far from the location of the previous discovery. The specimens were later renamed Dilophosaurus, based on the double crest clearly visible in the new skeleton.
     
    There is another species of Dilophosaurus (D. sinensis), which may or may not belong to this genus. It is possibly closer to the bizarre Antarctic theropod Cryolophosaurus, based on the fact that the anterior end of the jugal does not participate in the internal antorbital fenestra and that the maxillary tooth row is completely in front of the orbit and ends anterior to the vertical strut of the lacrimal. This species was recovered from the Yunnan Province of China in 1987, with the prosauropod Yunnanosaurus and later described and named in 1993 by Shaojin Hu.
     
    A third species, D. breedorum, was coined by Samuel Welles through Welles and Pickering (1999). This species was based upon crested specimen UCMP 77270. Welles' original material lacked well-preserved crests, and he suggested that the crested specimens pertained to a different species. He was unable to complete a manuscript describing this during his lifetime, and the name eventually came out in a private publication distributed by Pickering. This species has not been accepted as valid in other reviews of the genus.
     
    Dilophosaurus was prominently featured both in the 1993 movie Jurassic Park and in the original novel by Michael Crichton. In the film version, Dilophosaurus has a retractable neck frill around its neck (much like a frill-necked lizard), and spits blinding poison, aiming for the eyes to blind and paralyze its prey (much like a spitting cobra). There is no evidence to support either the frill or the venom spitting, which was acknowledged by Crichton as creative license.In the film, Steven Spielberg also reduced the size of Dilophosaurus to 3 feet (0.91 m) tall and 5 feet (1.5 m) long, much smaller than it was in reality. Jurassic Park merchandise, including toys and video games (such as Jurassic Park: Operation Genesis and the arcade games The Lost World: Jurassic Park and Jurassic Park III), often include Dilophosaurus.
     
    Despite its inaccuracies, the Jurassic Park Dilophosaurus has been taken up by others. Several other video games, such as ParaWorld and Jurassic Wars, and Ice Age: Dawn of the Dinosaurs feature Dilophosaurus modeled after the representations in Jurassic Park, and The Whitest Kids U'Know sketch "Dinosaur Rap", a music video for Trevor Moore's "Gettin' High With Dinosaurs" features a Dilophosaurus, complete with a short frill. One video game, 2008's Turok, features Dilophosaurus based more closely on real fossils and displays their correct size. Dilophosaurus was also featured in the documentary When Dinosaurs Roamed America, killing an Anchisaurus and scaring off a pack of Syntarsus (now known as Megapnosaurus).
     
     
    http://en.wikipedia.org/wiki/Dilophosaurus

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  6. Pisanosaurus by Moondawg

    Pisanosaurus
    Pisanosaurus mertii (the name comes from "Pisano", who was an associate of the finder, and "saurus" meaning lizard or reptile) is a primitive bipedal Ornithischian dinosaur from the Late Triassic.
    Pisanosaurus was 3.2 feet (1 meter) in length and 12 inches (30.48 centimeters) in height. Its weight estimate is just under 8.8 pounds (four kilograms). These estimates vary due to the incompleteness of the fossil.
     
    Pisanosaurus is known from a fragmented skeleton found in Argentina. It is very basal within Ornithischia; the postcrania seem to lack any good ornithischian synapomorphy; it has even been suggested the fossil is a chimera.
     
    Pisanosaurus (meaning "Pisano lizard") is a genus of primitive ornithischian dinosaur from the Late Triassic of what is now South America. It was a bipedal herbivore described by Argentine paleontologist Rodolfo Casamiquela in 1967. Only one species, the type, Pisanosaurus mertii, is known, based on one partially complete skeleton. The fossils were discovered in Argentina's Late Triassic Ischigualasto Formation, from around 228 to 216.5 million years ago.
     
    The exact classification of Pisanosaurus has been the topic of debate by scientists for over 40 years; the current consensus is that Pisanosaurus is the oldest known ornithischian, part of a diverse group of dinosaurs which lived during nearly the entire span of the Mesozoic Era.
     
    Based on the known fossil elements, Pisanosaurus was a small, lightly-built dinosaur approximately 1 m (3 ft 3 in) in length and 30 cm (12 in) in height. Its weight was between 2.27–9.1 kg (5–20 lb). These estimates vary due to the incompleteness of the fossil. The tail of Pisanosaurus has been reconstructed as being as long as the rest of the body, based on other early ornithischians, but as a tail has not been recovered, this is speculative. It was bipedal and, like all ornithischians, was probably exclusively herbivorous.
     
    Pisanosaurus mertii was described by Argentine paleontologist Rodolfo Casamiquela in 1967. The name Pisanosaurus honors Juan A. Pisano, an Argentine paleontologist, while saurus is derived from the Greek sa????, meaning "lizard". Pisanosaurus is known from a single fragmented skeleton found in Argentina. It is based on a specimen given the designation PVL 2577, which was discovered in the Ischigualasto Formation.
     
    The fossils of Pisanosaurus were discovered in Argentina's Ischigualasto Formation. Originally dated to the Middle Triassic, this formation is now believed to belong to the Late Triassic Carnian stage, around 228 to 216.5 million years ago. Pisanosaurus shared its habitat with rhynchosaurs, cynodonts, dicynodonts, prestosuchids, ornithosuchids, aetosaurs, and primitive dinosaurs. The early carnivorous dinosaur Herrerasaurus lived in this area and at this time, and may have fed upon Pisanosaurus.

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  7. Sellosaurus by Moondawg

    Sellosaurus
    Sellosaurus is the name given to a genus of prosauropod dinosaur that lived in Triassic Europe, 225 mya. Like other prosauropods, it had a thumb claw it may have used to defend itself, and reach for food.
    Sellosaurus is one of the more well-known prosauropods. Over twenty skeletons have been discovered. These fossils comprise what is believed to be at least three separate species. The dinosaur Efraasia, a prosauropod from the same location, was long thought to be the same as Sellosaurus, but this has been recently disproved.
     
    Sellosaurus is one of the more well-known prosauropods. Over twenty skeletons have been so far discovered. These fossils were found in strata dated to the middle Late Triassic and located in Nordwurttemberg, Germany. The remains comprise what is believed to be at least three separate species. The dinosaur Efraasia, a prosauropod from the same location, was long thought to be the same as Sellosaurus, but this has been recently disproved.

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  8. Lufengosaurus by Moondawg

    Lufengosaurus
    Lufengosaurus, (, meaning "Lufeng Lizard"), was a prosauropod dinosaur which lived during the Early Jurassic period in what is now southwestern China. At about 6 metres (20 ft) long, it was the first complete dinosaur skeleton mounted in China and a commemorative postage stamp was issued in 1958 to celebrate the event.
     
    Named by C.C. Young in 1941, remains of the type species, L. huenei, were found in the Lower Lufeng Formation (Lower Jurassic) of Yunnan Province in China. A second species was named by Young a few years later. L. magnus was, as its name suggests, a significantly (up to 1/3rd) larger creature than L. huenei. Lufengosaurus is still found in Bajocian stage deposits of China, making it one of the few "prosauropod" genera to survive into the Middle Jurassic.
     
    In 1981, Cooper suggested Lufengosaurus and Yunnanosaurus were species of the South African genus Massospondylus. However, a recent reanalysis of the skull of Lufengosaurus huenei establishes it as a distinct genus separate from either Massospondylus or Yunnanosaurus.
     
    Like all prosauropods, Lufengosaurus had much longer hindlimbs than forelimbs and was probably bipedal some of the time, especially when browsing for food. It was herbivorous, although it had sharp claws (with an especially large thumb claw) and teeth. These features have been used to support claims that Lufengosaurus may have been at least partially omnivorous, but the sharp teeth witnessed in Lufengosaurus and other prosauropods are similar to those seen in iguanaian lizards - which are herbivorous.Alternatively, the claws may have been used for defense or raking foliage from trees.

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  9. Oryctodromeus by Moondawg

    Oryctodromeus
    Oryctodromeus (meaning "digging runner") was a genus of small ornithopod dinosaur, the fossilized remains of which have been found in rocks dating from the middle Cretaceous Blackleaf Formation of southwestern Montana (Cenomanian stage), roughly 95 million years ago. A member of the small, presumably fast-running herbivorous family Hypsilophodontidae, Oryctodromeus is the first dinosaur published that shows evidence of burrowing behavior.
     
    Oryctodromeus is based on MOR 1636a, a partial skeleton of an adult individual including: the premaxillae (upper beak); part of the braincase; three neck, six back, seven hip, and twenty-three tail vertebrae; ribs; the shoulder girdle; an arm (minus the hand); both tibiae and an incomplete fibula; and a metatarsal. Two additional individuals, both juveniles about 55 to 65% the size of MOR 1636a, are represented by MOR 1636b. Unlike many other ornithopod dinosaurs, Oryctodromeus lacked bony tendons that stiffened the tail, which would have made moving about inside a small burrow easier. Additionally, it shows adaptations in the jaws, forelimbs, and pelvis that could have helped move and manipulate soil.
     
    The authors pointed out that Oryctodromeus had only modest forelimb modifications in comparison to dedicated burrowing animals, like moles, echidnas, and wombats. Instead, it was comparable to, but somewhat more specialized for digging than animals that both run and burrow today, like aardwolves, cavies, hyenas, and rabbits. Because it was a biped, it could have a more modified forelimb without affecting its ability to run.
     
    Under a cladistic analysis, Oryctodromeus was found to be basal within Euornithopoda and a close relative of the hypsilophodonts Orodromeus and Zephyrosaurus, which are also known from the Cretaceous of Montana. These two animals share adaptations with Oryctodromeus that may have been used for burrowing, such as a broad snout. Additionally, Orodromeus specimens have been found preserved in a similar way, suggesting that they too were in burrows. This would not be the first time that a hypsilophodont has been suggested as a burrower; Robert Bakker has informally claimed since the 1990s that Drinker, from the late Jurassic of Wyoming, lived in burrows, but this has yet to be published.
     
    The three Oryctodromeus individuals were found buried within the remains of an underground den or burrow, measuring about 2 meters long (6.5 feet) and 70 centimeters wide (2.3 ft). The skeletons were densely packed and disarticulated, indicating that the animals died and decayed within the burrow. The burrow is similar to those made by hyenas and puffins today. It was filled with sand, and the resulting sandstone stands out against the surrounding mudstone and claystone.
     
    There are two turns in the preserved burrow section, and smaller secondary sandstone cylinders of various sizes (a few centimeters or inches in cross-section at most) that were probably made by smaller animals sharing the burrow (commensal). The burrow closely fits the probable proportions of the adult dinosaur, another indication that it was the digger.
     
    As a hypsilophodont, Oryctodromeus would have been a small, swift herbivore. This aspect, coupled with where it was discovered, gives it its name: Oryctodromeus cubicularis translates as "digging runner of the lair", in reference to its presumed lifestyle. The adult Oryctodromeus itself measured 2.1 m long (6.8 ft) and would have weighed about 22-32 kilograms (50-70 pounds), and the juveniles would have been about 1.3 m long (4.3 ft). The presence of juveniles with the adult suggests parental care, and that at least one motivation for burrowing was to rear the juveniles. The size of the juveniles suggests an extended period of parental care.

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  10. Pedopenna by Moondawg

    Pedopenna
    Pedopenna ("foot feather") was a small, feathered, maniraptoran dinosaur from the Daohugou Beds in China. It is possibly older than Archaeopteryx, though the age of the Daohugou Beds where it was found is debated. Some estimates give an Early Cretaceous age, but the latest radiometric dating shows them to be late Middle Jurassic (Callovian) (c.140-168 mya).
     
    The name Pedopenna refers to the long pennaceous feathers on the metatarsus; daohugouensis refers to the locality of Daohugou, where the holotype was found. Pedopenna daohugouensis probably measured 1 meter (3 ft) or less in length, but since this species is only known from the hind legs, the actual length is difficult to estimate. Pedopenna is classified as a paravian (Paraves), the group of maniraptoran dinosaurs that includes Aves and their closest relatives.
     
    The feet of Pedopenna resembled those of the related troodontids and dromaeosaurids (which together form the group Deinonychosauria), though were overall more primitive. In particular, the second toe of Pedopenna was not as specialized as in deinonychosaurs. While Pedopenna did have an enlarged claw and slightly shortened second toe, it was not as highly developed as the strongly curved, sickle-like claws of its relatives.
     
    Xu and Zhang, who interpreted the Daohugou fossil beds where Pedopenna was found as mid to late Jurassic in age, used the presence of such a primitive member of the avian lineage, in combination with many primitive members of closely related lineages there, to support the idea that birds originated in Asia.
     
    The avian affinities of Pedopenna are further evidence of the dinosaur-bird evolutionary relationship. Apart from having a very bird-like skeletal structure in its legs, Pedopenna was remarkable due to the presence of long pennaceous feathers on the metatarsus (foot). Some deinonychosaurs are also known to have these 'hind wings', but those of Pedopenna differ from those of animals like Microraptor. Pedopenna hind wings were smaller and more rounded in shape. The longest feathers were slightly shorter than the metatarsus, at about 55 mm (2 in) long. Additionally, the feathers of Pedopenna were symmetrical, unlike the asymmetrical feathers of some deinonychosaurs and birds. Since asymmetrical feathers are typical of animals adapted to flying, it is likely that Pedopenna represents an early stage in the development of these structures. While many of the feather impressions in the fossil are weak, it is clear that each possessed a rachis and barbs, and while the exact number of foot feathers is uncertain, they are more numerous than in the hind-wings of Microraptor. Pedopenna also shows evidence of shorter feathers overlying the long foot feathers, evidence for the presence of coverts as seen in modern birds. Since the feathers show fewer aerodynamic adaptations than the similar hind wings of Microraptor, and appear to be less stiff, suggests that if they did have some kind of aerodynamic function, it was much weaker than in deinonychosaurs and birds. Xu and Zhang, in their 2005 description of Pedopenna, suggested that the feathers could be ornamental, or even vestigial. It is possible that a hind wing was present in the ancestors of deinonychosaurs and birds, and later lost in the bird lineage, with Pedopenna representing an intermediate stage where the hind wings are being reduced from a functional gliding apparatus to a display or insulatory function.

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  11. Megapnosaurus by Moondawg

    Megapnosaurus
    Megapnosaurus (meaning "big dead lizard", from Greek = "big", = "not breathing", "dead", = "lizard") was a dinosaur of the theropod family Coelophysidae, formerly called Syntarsus (named by Raath, 1969), living during the Early Jurassic. It was renamed by American entomologist Dr. Michael Ivie (Montana State University of Bozeman), Polish Australian Dr. Adam Slipinski, and Polish Dr. Piotr Wegrzynowicz (Muzeum Ewolucji Instytutu Zoologii PAN of Warsaw), the scientists who discovered that the genus name Syntarsus was already taken by a colydiine beetle described in 1869.
     
    Some paleontologists did not like the name Megapnosaurus. This was partially because taxonomists are generally expected to allow original authors of a name to correct any mistakes that may have arisen from their work. Raath was aware of the synonymy between the dinosaur Syntarsus and beetle Syntarsus, but the group who published Megapnosaurus had been led to believe Raath was deceased and proceeded accordingly. Megapnosaurus remains a valid name, though whether it can be treated as synonymous with Coelophysis is an open question.
     
    It is almost identical to Coelophysis, and Yates (2005) suggested that Megapnosaurus was possibly synonymous with Coelophysis. In 2004, Raath co-authored two papers in which he argued that "Syntarsus" (Raath continued to use the old, invalid, name) was a junior synonym of Coelophysis.
     
    Megapnosaurus measured up to 3 meters (10 ft) long from nose to tail and weighed about 32 kilograms (70 lb). The bones of 30 Megapnosaurus individuals were found together in a fossil bed in Zimbabwe, so paleontologists think it may have hunted in packs. The various fossils attributed to Megapnosaurus have been dated over a relatively large time span - the Hettangian, Sinemurian, and Pliensbachian stages of the Early Jurassic - meaning the fossils represent either a highly successful genus or a few closely related animals all currently assigned to Megapnosaurus.
     
    Megapnosaurus is a good example of how dinosaurs spread across the globe from their ancestral habitats (which was possibly South America). This small predator had the same basic features found in early dinosaurs, and its appearance in both Africa and the southwestern U.S. indicates that it migrated through the continents, which at the time were joined together as Pangaea. There is species-level differentiation between the African and U.S. specimens, again supporting the migration and adaptation theories.
     
    The African species (M. rhodesiensis) is known from almost 30 specimens. The North American species (M. kayentakatae) had small crests and may show an evolutionary step toward later and larger coelophysoids, such as the more derived Dilophosaurus. Both possess a weak joint between the premaxillary and the maxillary bones, creating a hooked premaxillary jaw. This led to the early hypothesis that dinosaurs such as these were scavengers, as the front teeth and bone structure were thought to be too weak to take down and hold struggling prey.

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  12. Alioramus by Moondawg

    Alioramus ( meaning 'different branch') is a genus of tyrannosaurid theropod dinosaur from the Late Cretaceous Period of Asia.
     
    The type and only species, A. remotus, is known from a partial skull and three metatarsals recovered from Mongolian sediments which were
    deposited in a humid floodplain between 70 to 65 million years ago. These remains were
    named and described by Russian paleontologist Sergei Kurzanov in 1976. Its relationships
    to other tyrannosaurid genera are unknown, but some experts believe Alioramus is closely
    related to the contemporaneous Tarbosaurus, or is a juvenile of that genus.
     
    While very little skeletal material is known, Alioramus was probably bipedal like most
    theropods, and its sharp teeth indicate that it was a carnivore. It was smaller than
    tyrannosaurids like Tarbosaurus and Tyrannosaurus, but its adult size is difficult to
    estimate since it is known mainly from a skull, which may belong to a juvenile. Alioramus
    is characterized by the row of five bony crests along the top of its snout, and also has
    more teeth than any other tyrannosaurid. Its skull is lower than those of other
    tyrannosaurids, but this might be a juvenile feature.
     
    Alioramus was estimated at between 5 and 6 meters (16.5 to 20 ft) in length when
    originally described by Sergei Kurzanov in 1976. Kurzanov, however, did not correct for
    lengthening of the skull by deformation during fossilization, which may indicate a shorter
    overall body length for this individual. If this specimen is a juvenile, then adult
    Alioramus would have reached greater lengths, but no confirmed adult specimens are known.
     
    Inspired by the Zoo Tek Brains Trust

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  13. Gobisaurus by Moondawg

    Gobisaurus is an ankylosaur from the Upper Cretaceous Ulansuhai Formation (Nei Mongol Zizhiqu) of China.
     
    The holotype consists of a skull and as yet undescribed postcranial remains. Along with its sister taxon Shamosaurus, Gobisaurus is "nested deep within the ankylosaurid lineage as the first successive outgroup to (the subfamily) Ankylosaurinae" (Vickaryous et. al., 2004). This is a large ankylosaur, with a skull measuring 46 cm. in length and 45 cm. across. The name means "Gobi (Desert) lizard," referring to its discovery by the Sino-Soviet Expeditions (1959–1960) in the Gobi Desert of Mongolia. The genus is monotypic, containing only G. domoculus.

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  14. Cetiosauriscus by Moondawg

    Cetiosauriscus (meaning "whale-lizard-like" i.e. "Cetiosaurus-like") was a close relative of Diplodocus and lived in the Middle to Late Jurassic Period of England.
     
    It was first named by German palaeontologist Friedrich von Huene, in 1927 and is known from a series of vertebrae from the rear half of the skeleton. It has been estimated that this creature stood 6 metres high and was 15 metres in length, weighing about 9 tonnes.
     
    It may have been preyed on by carnivores such as Megalosaurus and Eustreptospondylus.

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  15. Agilisaurus by Moondawg

    Acrocanthosaurus (pronounced ak-ro-KAN-tho-SAWR-us; meaning 'high-spined lizard') is a genus of allosauroid theropod dinosaur that existed in what is now North America during the mid-Cretaceous Period
     
    The skull of Acrocanthosaurus, like most other allosauroids, was long, low and narrow. The weight-reducing opening in front of the eye socket (antorbital fenestra) was quite large, more than a quarter of the length of the skull and two-thirds of its height. The outside surface of the maxilla (upper jaw bone) and the upper surface of the nasal bone on the roof of the snout were not nearly as rough-textured as those of Giganotosaurus or Carcharodontosaurus. Long, low ridges arose from the nasal bones, running along each side of the snout from the nostril back to the eye, where they continued onto the lacrimal bones. This is a characteristic feature of all allosauroids. Unlike Allosaurus, there was no prominent crest on the lacrimal bone in front of the eye. The lacrimal and postorbital bones met to form a thick brow over the eye, as seen in carcharodontosaurids and the unrelated abelisaurids. Nineteen curved, serrated teeth lined each side of the upper jaw, but a tooth count for the lower jaw has not been published. Acrocanthosaurus teeth were wider than those of Carcharodontosaurus and did not have the wrinkled texture that characterized the carcharodontosaurids. The dentary (tooth-bearing lower jaw bone) was squared off at the front edge, as in Giganotosaurus, and shallow, while the rest of the jaw behind it became very deep. Acrocanthosaurus and Giganotosaurus shared a thick horizontal ridge on the outside surface of the surangular bone of the lower jaw, underneath the articulation with the skull.

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  16. Indosuchus by Moondawg

    Indosuchus raptorius was an abelisaurid dinosaur from the Late Cretaceous Period (65 to 70 million years ago - the Maastrichtian era),
     
    A primitive theropod related to Abelisaurus. Like most theropods, Indosuchus was a bipedal carnivore. It was possibly 20 feet (6 meters) long, and had a crested skull, flattened on the top.
     
    Because only some skull elements have been found, Indosuchus placement has been somewhat erratic. Although it's now somewhat firmly placed within the Abelisauridae, it has been also grouped with allosaurs and tyrannosaurs. The discovery of other abelisaurid species like Carnotaurus sastrei has helped clarify its position.

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  17. Paranthodon by Moondawg

    Paranthodon (Meaning "Beside Anthodon") was a dinosaur from the middle of the Cretaceous. It lived in what is now South Africa.
     
    It is classified as a stegosaur. The type species, Paranthodon africanus, comes from a partial skull first described as Palaeoscincus africanus in 1912. It was reclassified as Paranthodon africanus in 1929 by the famed Franz von Nopsca. It owes its name to the fact that its jaw was found near the fossils of a Permian pareiasaur named Anthodon.
     
     
    * Inspired by the Zoo Tek Brains Trust

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  18. Chasmatosaurus by Moondawg

    Chasmatosaurus is an extinct genus of archosauriform reptile that grew about 4 m (12 ft 8 in) long from the Early Triassic of China.
     
    Also called Proterosuchus, Chasmatosaurus was a crocodile-like creature that probably hunted like its extant descendants, attacking drinking prey on the waterside. Its upper jaw arched down at the front, and the creature had teeth on its palate- a primitive trait. it had a main cameo in walking with monsters attacking a herd of lystrosaurus. it is a possibility that chasmatosaurus is an ancestor of crocodillians.

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  19. Brachychampsa by Moondawg

    This freshwater, carnivorous reptile is among the very earliest alligatoroids known to science.
     
    The first Brachychampsa fossil was discovered in Montana's heck Creek Formation—an ancient suite of rocks that was laid down near the end of the Cretaceous period. That individual animal lived not so long before the Cretaceous-Tertiary extinction that wiped out many of Earth's species some 65 million years ago.
     
    Brachychampsa had short teeth and a large mouth that packed more power than those of living gators. These oral characteristics suggest that Brachychampsa may have preyed on turtles, which were very common in the heck Creek fauna.
     
    The first alligator ancestors evolved some 245 million years ago. About 80 million years ago, during the Cretaceous period, crocodilians appeared. This group includes alligatoroids, such as Brachychampsa, as well as their close relatives the crocodiles and caimans.
     
    Many of these ancient animals were survivors of the Cretaceous-Tertiary extinction, though no one knows why they lived when so many others perished.
     
    Modern alligators are still closely related to their ancient ancestors and look much like their relatives did 80 million years ago.
     
    This animal was tricky :D but i managed to get the eggs to hatch :D

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  20. Troodon by Moondawg

    Tro-odon (or Troödon) was a relatively small, bird-like dinosaur from the Late Cretaceous Period (75-65 mya). Discovered in 1855, it was among the first dinosaurs found in North America.
     
    Its name (pronounced "Tro-odon") is Greek for "wounding tooth", referring to the
    dinosaur's serrated teeth (although these may actually have been adapted for a herbivorous
    diet). They were formerly known as saurornithoidids. Troodon was a small dinosaur, around 2 meters (6.5 ft) in length, 1 meter (3 ft) tall, and
    weighed 60 kilograms (130 lb). It had very long, slender limbs, suggesting that the animal was able to move quickly. It had long 'arms' that folded against the wall of the thorax like a bird's. It had large, retractable sickle-shaped claws on its second toes, which were raised off the ground when running. Because of these features scientists regard
     
    Troodon as a member of the Maniraptora. Its eyes were large (perhaps suggesting nocturnal
    activity) and slightly forward facing, giving Troodon some depth perception. In fact most reconstructions give Troodon eyes which point in a more forwards direction than almost any
    other dinosaur, which implies that it had better binocular vision than most dinosaurs.
    Their light skulls contained a capsule similar to those found in ostrich dinosaurs.
     
    Troodon had one of the largest known brains of any dinosaur, relative to its body mass
    (comparable to modern birds). Hence it is believed to have been one of the most intelligent dinosaurs, even more intelligent than mammals of that era. Eggs have also been discovered, in nests.
     
    Troodon is known from the Judith River Formation and the upper Two Medicine Formation of Montana, the Judith River Group of Alberta, the Horseshoe Canyon Formation of Alberta, the
     
    North Slope of Alaska, and in the famous Lance and heck Creek Formations of the USA. There
    is some evidence that Troodon favored cooler climates, as it seems to have been particularly abundant

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  21. Chindesaurus by Moondawg

    Chindesaurus (CHIN-dee-SAWR-us - Chinde (Navajo, chiindii) meaning "ghost or evil spirit" and Greek sauros meaning "lizard") is a genus of theropod dinosaur named after the Chinde Point.
     
    Chindesaurus was a basal theropod which lived around 225 million years ago during the Late Triassic. It was between 6 and 12 feet (3.7 m) long, and was formally described by Long and Murry in 1995. The type species, Chindesaurus bryansmalli, is named in honor of the discoverer.

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  22. Juravenator by Moondawg

    Juravenator is a genus of small (2.5 feet long) coelurosaurian dinosaur, which lived in the area which would someday become the Jura mountains of Germany, 150 million years ago.
    Juravenator was originally published as a member of the family Compsognathidae, making it a close relative of Sinosauropteryx and Sinocalliopteryx, for which there is fossil evidence of a downy, feather-like covering, yet a patch of fossilized Juravenator skin shows only normal dinosaur scales, with no sign of feathers at all. While it may simply have never had feathers, paleontologist Mark Norell suggest that the presence of scales on the Juravenator tail could mean a number of things:
     
    Juravenator could have lost its feathers secondarily on at least some parts of its body, like some modern, partially featherless birds.
    Feathers could have evolved more than once in different types of dinosaur.
    Since the only known Juravenator skeleton is juvenile, it could be that this species only grew a significant covering of feathers as they aged, or lost feathers seasonally.
    The feathers might simply have not been preserved in this specimen. "Feathers are really just difficult things to preserve," Norell says, though Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles County points out that the fossil skin does not show the follicles normally associated with dinosaur skin that has lost its feathers.
    Additionally, subsequent studies have found problems with the initial study that placed Juravenator among the compsognathids. Rather than grouping it with Sinosauropteryx and other compsognathids, Butler et al. found that it was not a compsognathid, but rather a basal member of the group Maniraptora. Studies conflict on whether or not compsognathids belong to this later group or are more primitive, though all other maniraptoran skin impressions also show evidence of feathers.
     
    The fossil, found in 1998 by amateur paleontologist Klaus-Dieter Weiß in a lime pit near Eichstätt, had been nicknamed Borsti in German, a name commonly given to bristle-haired dogs, on the assumption the creature was endowed with bristly protofeathers.

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  23. Hipparion by Moondawg

    Hipparion (Greek, "pony") is an extinct genus of horse.
     
    It resembled the modern horse, but still had vestigal outer toes (in addition to its hoof). These did not touch the ground. Hipparion was about 1,40 m (4 ft 8 in) tall at the shoulder.
     
    Must have Dino Digs and/or Complete Collection in order for food to show up.

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  24. Aviatyrannis by Moondawg

    Aviatyrannis is a genus of tyrannosaurid dinosaur from the Kimmeridgian stage of the Late Jurassic found in Portugal.
     
    It was described by Oliver Rauhut in 2003. The name means "Jurassic grandmother tyrant". It is one of the oldest tyrannosaurs ever found, the oldest being Guanlong (or Iliosuchus if it is indeed tyrannosauroid).
     
    Aviatyrannis was perhaps a contemporary of another ancient tyrannosaur, the American Stokesosaurus. Aviatyrannis was even originally assigned to Stokesosaurus, and its fragmentary remains maintain the question of their synonymity open.
     
    Like other early tyrannosaurs, Aviatyrannis was rather small. The holotype, for example, is an ilium only 90 millimeters long. The type species, Aviatyrannis jurassica, was described by Rauhut in 2003.
     
     
    Inspired by the Zoo Tek Brains Trust

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  25. Heterodontosaurus by Moondawg

    Heterodontosaurus (meaning "Different Toothed Lizard") was a small herbivorous dinosaur with sharp canine teeth which lived in the Early Jurassic of South Africa.
     
    It was similar to a Hypsilophodont in shape, and ate plants, despite its razor-sharp canines.
     
    Heterodontosaurus is currently known from specimens of the SAFM (South African Museum) from South Africa. There are two known morphologies of this genus, the second of which is thought by some to represent a different species. The type species, H. tucki, is from the Upper Elliot Formation of Hettangian (199-196 Million Years Ago) age. It is probably a senior objective synonym of Abrictosaurus, as has been suggested in the past.
     
    Heterodontosaurus was a small, fleetfooted ornithischian that reached a maximum size of about 3 feet. It had a long, narrow pelvis and a pubis which resembled those possessed by more advanced ornithischians.
     
    More unusual was that the hand of Heterodontosaurus had five fingers, two of which seem to be opposable. This configuration allowed Heterodontosaurus to grasp and manipulate food. The bone in the foot and ankle were fused in a manner reminiscent of those in birds.
     
    Another interesting feature is the specialization of teeth which gave rise to the animal's name. Most dinosaurs (and indeed most reptiles) have a single type of tooth in their jaws, while Heterodontosaurus had three. At the front of the jaw beside the beak were small teeth likely used for chopping off leaves and stems.
     
    Next in the jaw was a large pair of tusks whose purpose is unknown, but it is speculated that they were used as sexual displays. In that scenario, the tusks could have been used as weapons by rival males in disputes over mates and territories. The final type of teeth were tall and squared off. This type of teeth was well adapted for chewing. Fleshy cheeks helped keep the food in the mouth while chewing occurred. Chewing is relatively common in dinosaurs, but uncommon for other groups of reptiles.
     
    This bizarre suite of teeth has led to debate over what heterodontosaurs ate. Some scientists think heterodontosaurs were omnivores who used their differently-shaped teeth to eat both plants and small animals

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