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68-719: Murusraptor ("wall thief") is a genus of carnivorous megaraptoran theropod dinosaur from the Sierra Barrosa Formation , part of the Neuquén Group of Patagonia , in Argentina , South America . It is known from a single specimen that consists of a partial skull, ribs, partial pelvis, leg and other assorted skeletal elements. In 2001, Sergio Saldivia, preparator at the Museo Carmen Funes , thirty kilometres northeast of Plaza Huincul in
136-656: A 2013 review of patagonian theropods, which removed Megaraptora from the Carcharodontosauria and instead placed the group within Coelurosauria. More specifically, megaraptorans were found to be deep within the Tyrannosauroidea , a radiation of basal coelurosaurs including the famed tyrannosaurids . As Novas et al. (2013) removed Megaraptora from Neovenatoridae, they named a new family, Megaraptoridae, which contained all Megaraptorans apart from
204-465: A canyon wall discovered the skeleton of a theropod dinosaur new to science. During that year and 2002 the remains were secured. In 2016, the type species Murusraptor barrosaensis was named and described by Rodolfo Anibal Coria and Philip John Currie . The generic name is a combination of the Latin murus , "wall", a reference to the canyon wall, and raptor , "seizer". The specific name refers to
272-484: A much more slender humerus. The distal part of the humerus (near the elbow) has a well-developed system of condyles and grooves similar to that of coelurosaurs, particularly the dromaeosaurids. The ulna of megaraptorids is characteristic in several regards. The olecranon process is well-developed, though it is thin, blade-like, and extends as a crest longitudinally down the shaft of the ulna. In addition, megaraptorids have acquired another long, crest-like structure on
340-445: A number of unique features. Their forelimbs were large and strongly built, and the ulna bone had a unique shape in members of the family Megaraptoridae, a subset of megaraptorans which excludes Fukuiraptor and Phuwiangvenator . The first two fingers were elongated, with massive curved claws, while the third finger was small. Megaraptoran skull material is very incomplete, but a juvenile Megaraptor described in 2014 preserved
408-467: A pneumatic quadrate , as in a few allosauroids ( Sinraptor , Mapusaurus ) and tyrannosauroids. The dentary , which is only known in Australovenator , is long and graceful, with the first tooth smaller than the rest (as in tyrannosauroids). The mandible as a whole has only a single meckelian foramen, as in carcharodontosaurians, tyrannosaurids, and ornithomimids. However, the rear part of
476-652: A polytomy at the base of Tyrannosauroidea, based on the dataset of Apesteguia et al. (2016). A 2022 study by Naish and Cau , in contrast, classified Eotyrannus as an intermediate gracile tyrannosauroid outside of Megaraptora. Their research supported a tyrannosauroid position for megaraptorans, even though Eotyrannus itself was not a megaraptoran. They recovered Megaraptora as radiation of derived tyrannosauroids close to Tyrannosauridae, similar to that found by Porfiri et al. (2014). Juratyrant [REDACTED] Stokesosaurus [REDACTED] Sinraptor Sinraptor ( / s ɪ n ˈ r æ p t ər / )
544-647: A portion of the snout, which was long and slender. Leg bones referred to megaraptorans were also quite slender and similar to those of coelurosaurs adapted for running. Although megaraptorans were thick-bodied theropods, their bones were heavily pneumatized , or filled with air pockets. The vertebrae , ribs , and the ilium bone of the hip were pneumatized to an extent which was very rare among theropods, only seen elsewhere in taxa such as Neovenator . Other characteristic features include opisthocoelous neck vertebrae and compsognathid -like teeth. Megaraptorans were originally placed as basal tetanurans as part of
612-568: A sharp ridge on their lower edge in megaraptorids (non- Fukuiraptor megaraptorans). The carpus (wrist) of megaraptorans incorporated a semilunate (crescent-shaped) carpal similar to that of maniraptorans . Examinations of the forelimbs of megaraptorans by Rolando, Novas, and Porfiri et al., that were published in January 2023 show that the megaraptorans' forelimb bones are remarkably well-developed; powered by strong pectoral and front limb muscle that were functionally significant and important to
680-575: A vestigial fourth metacarpal , the hand bone that would have connected to the fourth finger in early dinosaurs. This was a primitive feature lost by most other tetanurans. The first two fingers had absurdly large unguals (claws); in Megaraptor the first claw was larger than the entire ulna. Unlike the large unguals of many other theropods (megalosauroids, for example), megaraptoran claws were thin and oval-shaped in cross-section. These claws also had asymmetrically-positioned grooves on their flat faces and
748-534: A widespread distribution. Phuwiangvenator and Fukuiraptor , the most basal and second most basal known members of the group, lived in Thailand and Japan , respectively. Megaraptoran material is also common in Australia, and the largest known predatory dinosaur from the continent, Australovenator , was a megaraptoran. Megaraptorans were medium to large-sized theropods, ranging from Fukuiraptor , which
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#1732780610252816-475: Is a clade of carnivorous theropod dinosaurs with controversial relationships to other tetanuran theropods. Its derived members, the Megaraptoridae are noted for their large hand claws and powerfully-built forelimbs, which are usually reduced in size in other large theropods. Megaraptorans are incompletely known, and no complete megaraptoran skeleton has been found. However, they still possessed
884-533: Is a genus of metriacanthosaurid theropod dinosaur from the Late Jurassic . The name Sinraptor comes from the Latin prefix "Sino", meaning Chinese, and "raptor" meaning robber. The specific name dongi honours Dong Zhiming . Despite its name, Sinraptor is not related to dromaeosaurids (often nicknamed "raptors") like Velociraptor . Instead, it was a carnosaur distantly related to Allosaurus . Sinraptor and its close relatives were among
952-477: Is a megaraptoran, one of a group of large predatory dinosaurs whose exact classification remains disputed. Once believed to be dromaeosaurids, they have since been classified as either allosauroid carnosaurs or as tyrannosauroid coelurosaurs. While the discovery of Murusraptor does not clarify as of yet the placement of this group of theropods, the specimen does add further clarity to some aspects of megaraptoran anatomy and potentially, eventual classification of
1020-601: Is asymmetrical when seen from the front due to the lateral condyle projecting further distally than the medial condyle. The tibia was also similar to that of coelurosaurs. It was a long and thin bone. The front of the lateral condyle of the tibia hooks downwards, similar to the condition in Neovenator, Tanycolagreus , and some tyrannosauroids. The medial and lateral malleoli are expanded and project away from each other, as in advanced tyrannosauroids (both) and carcharodontosaurians (medial malleolus only). The front surface of
1088-636: Is considered to be an immature specimen, as the cranial sutures in its braincase have not yet disappeared; this indicates it would have been potentially larger. Analysis of the skeleton further revealed anatomical features as-yet unseen in Megaraptora, particularly in the skull and hips . Analysis of the posterior of the skull indicates that, possibly like the related Megaraptor , Murusraptor likely had an elongated and narrow snout. The sacral ribs are hollow. Coria & Currie established some distinguishing traits of Murusraptor . The front branch of
1156-491: Is not unusual compared to other theropods. Megaraptorans also had very characteristic hands. The first two fingers were large and slender, but the third one was small. These relative differences in finger length are somewhat similar to the case in tyrannosauroids and various other basal coelurosaurs, but the megaraptoran trend of forearm and finger enlargement is opposite to the trend towards forearm diminishment which characterizes advanced tyrannosauroids. Megaraptor retained
1224-410: The centra , and a pair of large lateral pits known as pleurocoels . In fact, one or more pleurocoels were present in most megaraptoran vertebrae, and they connected to a complex system of numerous small air pockets within the vertebrae. This web-like internal structure of megaraptoran vertebrae (and that of a few other theropods) has been described as " camellate ". The proximal caudals (vertebrae at
1292-403: The ilia and ribs), which likely housed sinuses connected to the lungs, similar to modern birds. The slender leg bones and long metatarsals of several species indicate that members of this group likely had cursorial habits. Most megaraptorans are part of the family Megaraptoridae, which was named by Fernando Novas and his colleagues in 2013. This family is united by several adaptations of
1360-529: The processus basipterygoidei . The chevron bones are rather straight. The braincase of Murusraptor shows more similarities to non-maniraptoran coelurosaurs , particularly tyrannosaurids , than to non-coelurosaurs such as allosaurids or ceratosaurids , although its Reptile Encephalization Quotient was nonetheless within the range of allosauroids such as Allosaurus , Giganotosaurus , and Sinraptor and its neurosensorial capabilities were thus most likely inferior to those of tyrannosaurids. Murusraptor
1428-593: The type species , was described by Currie and Zhao in 1994. A second species, originally named Yangchuanosaurus hepingensis by Gao in 1992, may actually represent a second species of Sinraptor . Whether or not this is the case, Sinraptor and Yangchuanosaurus were close relatives, and are classified together in the family Metriacanthosauridae . Gregory S. Paul proposed that S. dongi would reach 8 metres (26 ft) in length and 1.3 metric tons (1.4 short tons) in body mass, while Holtz estimated it to be 8.8 metres (29 ft) in length. The dentition of Sinraptor
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#17327806102521496-454: The "lightning ridge megaraptoran" by Bell et al. supported the idea that megaraptorans were tyrannosauroids based on the fact that Porfiri et al. (2014) incorporated skull data from Megaraptor and a wider variety of coelurosaurians compared to Benson, Carrano, & Brusatte (2010). Motta et al . (2016) agreed, and proposed that a new fragmentary patagonian theropod, Aoniraptor , was a non-megaraptorid megaraptoran. Their study also noted
1564-459: The 1990s due to the large hand claws being misidentified as foot claws. However, these mistakes were rectified after closer inspection of the holotype (in the case of Fukuiraptor ) or the discovery of new specimens (in the case of Megaraptor ). By the mid-to-late 2000s, they were considered to be basal tetanurans, usually members of Allosauroidea. Smith et al. (2008) reported Megaraptor -like ulnae from Australia, and found evidence that Megaraptor
1632-510: The K-Pg extinction. The authors also noted that while their phylogenetic analysis didn't support it, Australian megaraptorids likely formed a paraphyletic grade leading to South American forms. The genera which make up Megaraptora had been placed in a number of different theropod groups before the formation of the clade in 2010. Megaraptor and Fukuiraptor were independently considered to be giant dromaeosaurids when they were first discovered in
1700-431: The Megaraptora within the theropod evolutionary tree. The cladogram follows Coria & Currie (2016), who added Murusraptor to the study and utilized the family Megaraptoridae, which was originally named by Novas et al. (2013). Allosauridae [REDACTED] Fukuiraptor Megaraptor Aerosteon Orkoraptor [REDACTED] The type specimen of Murusraptor shows signs of severe infections around
1768-406: The added effect of making the portion of the femur near the hip socket rectangular, when seen from above. In non-coelurosaur theropods, the greater trochanter is small, making the femur teardrop-shaped when seen from above. The femoral head is slightly upturned as in carcharodontosaurians (particularly carcharodontosaurids) and some coelurosaurs. In megaraptorans, the portion of the femur near the knee
1836-414: The basal ("primitive") taxon Fukuiraptor . They found little evidence that Chilantaisaurus , Neovenator , or Siats were megaraptorans, but they did place the tyrannosauroid Eotyrannus within Megaraptora. Despite the hypothesized close relation between megaraptorans and tyrannosaurids, Novas et al. noted that the megaraptoran lineage had a functional morphology which diverged in a direction opposite to
1904-542: The base of the tail) had a longitudinal ridge running along their lower surface, similar to the case in Neovenator but unlike tyrannosauroids. They also had a pair of lateral ridges which stretched downwards from the transverse processes to the centra. These ridges, known as centrodiapophyseal laminae , defined a large depression (infradiapophyseal fossa) under the transverse processes. Although these ridges were also present in dorsal (back) vertebrae and have been found in other theropods, megaraptorans were practically unique in
1972-413: The distal tip of the tibia (near the ankle) had the form of a flattened facet for the reception of the astragalus bone of the ankle, similar to the case in coelurosaurs. The inner edge of this facet was defined by a ridge, a feature unique to megaraptorids. The upper edge of the facet lacked a well-defined supra-astragalar buttress, unlike allosauroids. The ascending process of the astragalus, which lays on
2040-735: The earliest members of the Jurassic carnosaurian radiation. Sinraptor still remains the best-known member of the family Metriacanthosauridae, with some older sources even using the name "Sinraptoridae" for the family. The holotype specimen of Sinraptor was uncovered from the Shishugou Formation during a joint Chinese/Canadian expedition to the northwestern Chinese desert in 1987, and described by Philip J. Currie and Zhao Xijin in 1994. Standing nearly 3 meters (9.8 feet) tall and measuring roughly 7.6 meters (25 feet) in length, two species of Sinraptor have been named. S. dongi ,
2108-423: The entire Theropoda . Furthermore, a unique combination of traits is present that are in themselves not unique. In the braincase, the processus basipterygoidei are situated at the front underside of the basisphenoid while the entrance of the deep depression of the recessus basisphenoideus is directed obliquely upwards and to the rear. The basisphenoid shows a shallow wide notch between the tubera basilaria and
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2176-430: The facet, is expanded into a large trapezoidal plate of bone, similar to coelurosaurs but unlike the small, triangular ascending process of allosauroids. Fukuiraptor , Australovenator , and Aerosteon have a distinct forward-pointing prong on the outer edge of the astragalus, and Fukuiraptor and Australovenator have an additional prong that projects backwards. The fibula is also long and strongly tapers away from
2244-474: The fact that their centrodiapophyseal laminae were well-developed at the base of the tail, sometimes even more so than the dorsal vertebrae. Only spinosaurids share this feature. The strong development of these ridges may indicate that the tail was deep and muscular. The dorsal ribs were thick and curved yet hollow and pierced by a hole near their connection to the vertebrae. The gastralia (belly ribs) were wide and strongly built paddle-shaped structures, with
2312-479: The fact that they were strongly opisthocoelous . This means that they were convex from the front and concave from behind. Opisthocelous vertebrae are also characteristic of Allosaurus and sauropods , and they may facilitate high flexibility without sacrificing defense against shear forces . Otherwise, the cervicals were similar to those of carcharodontosaurians, with short neural spines , transverse processes (projecting rib facets) located around mid-length on
2380-465: The family Neovenatoridae within the allosauroid clade Carcharodontosauria . By the early 2020s, many studies had come to find that megaraptorans instead represented members of Coelurosauria , with their exact position within this group being uncertain. However, some studies still support an allosauroid classification. Megaraptorans were most diverse in the early Late Cretaceous period of South America, particularly Patagonia . However, they had
2448-497: The family Neovenatoridae. The cladogram follows Coria & Currie (2016), who added Murusraptor to the study and utilized the family Megaraptoridae, which was originally named by Novas et al. (2013). Allosauridae [REDACTED] Fukuiraptor Megaraptor Aerosteon Orkoraptor [REDACTED] However, an alternative hypothesis was forming, first published as an Ameghiniana abstract by Fernando Novas et al. (2012). Novas and his colleagues argued that
2516-407: The features used to link Neovenator to Megaraptora were more widespread than the 2010 paper implied, and that the proposed coelurosaurian convergences may have signified a legitimate connection between Megaraptora and Coelurosauria. In addition, they noted that Benson, Carrano, & Brusatte only sampled three coelurosaurs in their analysis. Novas et al .'s arguments were formulated and published in
2584-424: The highly derived hands, as well as enhanced humeral protraction; attributes that likely aided in prey capture. The femur (thigh bone) of megaraptorans is only known in Australovenator and Fukuiraptor , but it is similar to that of coelurosaurs in several respects. For example, the greater trochanter is well-developed and offset from the femoral shaft by a deep concavity. The size of the greater trochanter has
2652-453: The hip) has a much more pronounced scythe-like expansion at its tip, which is over 60% as long as the main shaft of the bone. This adaptation, known as a pubic boot, is also known in carcharodontosaurians and tyrannosaurids. The pubis is also expanded near its contact with the ilium. The left and right pubic bones are not entirely fused to each other, they are separated along their midline by an oval-shaped hole. A palaeobiogeographic assessment
2720-529: The ilium has a large depression known as a brevis fossa, which is visible from the outer face of the ilium. However, coelurosaurs and megaraptorans have a much smaller brevis fossa which occupies only a portion of the rear edge of the ilium, and it is mostly hidden from outside observers. The ischium (rear lower plate of the hip) is only known in Murusraptor . It is slightly expanded, similar to that of carcharodontosaurids. The pubis (front lower plate of
2788-441: The knee, as in coelurosaurs. It connects to a small facet on the outer edge of the astragalus (as in coelurosaurs) rather than a large facet on the upper edge (as in allosauroids). Near the knee and facing the tibia, the fibula has a wide groove or depression known as a proximomedial fossa. Metatarsal III, the foot bone which connected to the middle toe, was very long and slender in all megaraptorans, as in coelurosaurs. The joint for
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2856-499: The lacrimal is longer than the descending branch is high. In the lower jaw, the surangular shows a bone shelf at its outer side, under the groove between the front surangular opening and the notch for the upper rear branch of the dentary, contributing to the side joint. The sacral ribs are hollow and tube-like. The ischia are short, transversely flattened and vertically slightly widened. These last two traits are unequivocal autapomorphies , unique derived qualities, as they are unique within
2924-430: The left and right sides fused at the midline of the chest. These features signified that megaraptorans were wide-bodied theropods, akin to the condition in tyrannosaurids. Megaraptorans have a sigmoid (S-shaped) humerus (upper arm bone), similar to that of both basal allosauroids and basal coelurosaurs. Most megaraptorans had large, robust humeri akin to those of Allosaurus , but the basal-most member Fukuiraptor has
2992-491: The left side of its braincase. Two tooth marks, likely inflicted by another theropod, are visible in front of and below the nuchal crest on the skull. Due to the infections, the entire left side of the occiput , the back of the head, was deformed. Some of the ribs were also infected. Whether or not this contributed to the theropod's death remains unknown. [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] Megaraptora Megaraptora
3060-576: The mandible (as seen in Murusraptor ) was significantly more lightly built than that of tyrannosauroids. Preserved braincase material has similarities to both carcharodontosaurians and tyrannosauroids. The premaxillary teeth of Megaraptor were variably similar to those of tyrannosauroids, being small, incisiform (chisel-like) and D-shaped in cross section. However, Murusraptor 's premaxillary teeth were fang-like, as in non-tyrannosauroid theropods. Megaraptoran maxillary teeth show much variety between genera , although they were generally small compared to
3128-457: The megaraptorid radiation of Late Cretaceous Gondwana. The specimen also allowed for alternative phylogenetic testing as to the placement of megaraptorans as either tyrannosauroids or carcharodontosaurids. This was expanded upon by Lamanna et al. (2020) who hypothesized that the megaraptorid dispersal from Australia to South America (probably via Antarctica) came with an increase in body size, and that megaraptorids kept their large body size until
3196-457: The middle toe is tall and pulley-shaped, with a deep and crescent-shaped depression visible from below. The ilium (upper plate of the hip) was a heavily pneumatized bone, filled with air pockets and perforated by pits. The only other large theropod known to possess a pneumatic ilium is Neovenator . In some megaraptorans, the preacetabular blade has a notch along its front edge, as in tyrannosauroids but also in Neovenator . A stronger concavity
3264-528: The newly discovered theropod Siats in 2013, which they placed within Megaraptora. Fukuiraptor and Australovenator were consistently found to be close relatives of each other; this was also the case for Aerosteon and Megaraptor ; Orkoraptor was a "wildcard" taxon difficult to place with certainty. The cladogram below illustrates the most recent revision of the Benson, Carrano, & Brusatte (2010) hypothesis that megaraptorans were allosauroids within
3332-708: The other neovenatorids on the basis of several features spread out throughout the skeleton, particularly the large amount of pneumatization present. The pneumatic ilium of Aerosteon was particularly notable, as Neovenator was the only other taxon known to have that trait at the time. Neovenatorids were envisioned as the latest-surviving allosauroids, which were able to persist well into the Late Cretaceous due to their low profile and coelurosaur-like adaptations. Later studies supported this hypothesis, such as Carrano, Benson & Sampson large study of tetanuran relationships in 2012, and Zanno & Makovicky description of
3400-491: The paleobiology of this group of theropods. Their data also suggests these muscle attachments became increasingly pronounced through megaraptoran evolutionary history, being substantially better developed in derived taxa such as Australovenator and especially Megaraptor itself than in earlier genera such as Fukuiraptor . Their results further suggest that the highly specialized forelimbs were capable of highly complex movements, such as great extension and flexion, particularly in
3468-647: The provenance from the Sierra Barrosa Formation . The holotype , MCF-PVPH-411 , was found in a layer of the Sierra Barrosa Formation dating from the Coniacian . It consists of a partial skeleton with skull, of an immature individual. The skeletal elements recovered for this type specimen of Murusraptor include a partial skull consisting of a complete braincase with frontals and parietals, right lacrimal, prefrontal, postorbital, quadrate, pterygoid, epipterygoid and ectopterygoid, thirty-one teeth,
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#17327806102523536-421: The question of their classification. They found that megaraptorans lacked most of the key features in the hands of derived coelurosaurs including Guanlong and Deinonychus . Instead, their hands retain a number of primitive characteristics seen in basal tetanurans such as Allosaurus . Nevertheless, there are still a number of traits that support megaraptorans as members of the Coelurosauria. A 2016 study of
3604-422: The rear elements of the right lower jaw , twelve vertebrae from the back, sacrum and tail, eleven thoracic ribs, a single haemal arch or chevron bone, several gastralia, a third manual ungual, complete left ilium , part of a right ilium, proximal ends of both pubic bones , distal ends of the ischia, the right tibia , and a calcaneum . The holotype of Murusraptor is estimated to be 6.4 m (21 ft), but
3672-561: The similaritires between Aoniraptor , the enigmatic theropod Deltadromeus , and Bahariasaurus , a giant African theropod with remains destroyed by World War II bombings. Therefore, they suggested that Bahariasaurus and Deltadromeus were also basal megaraptorans, and that Aoniraptor , Bahariasaurus , and Deltadromeus could have formed a distinct family, the Bahariasauridae. A 2019 redescription of Murusraptor by Rolando, Novas, & Agnolín continued to find Megaraptora in
3740-580: The snout as well as parietal fragments. Teeth have been found in many genera. Collectively, megaraptorans can be reconstructed as having a long, lightly built skull with many relatively small teeth. Based on Megaraptor , the premaxillary bone at the tip of the snout is small, with a long and rod-like branch of bone which extends above the external nares (nostril holes). The nares themselves were very large and elongated, akin to some early tyrannosauroids ( Dilong , Proceratosaurus , etc.). The snout also had some similarities to carcharodontosaurids, namely
3808-573: The snout with minimal enamel ornamentation. Some megaraptorans, such as Orkoraptor, Australovenator, and Megaraptor , had teeth which were 8-shaped in cross section and completely unserrated from the front (similar to dromaeosaurids and compsognathids ), while Murusraptor had anterior serrations only at the tip of its teeth. Fukuiraptor had very laterally compressed and blade-like teeth (similar to carcharodontosaurs ) with both anterior and posterior serrations. The cervical (neck) vertebrae of megaraptorans were nearly unique among theropods in
3876-422: The straight upper edge of the maxilla and rectangular nasal bones. The parietal bones at the top of the skull, behind the eyes, had a strongly developed sagittal crest , as in tyrannosauroids. Otherwise, the rear part of the skull is rather simple, without any pronounced crests or bosses, although the lacrimal and postorbital bones did have rugose patches in some genera. Aerosteon and Murusraptor possessed
3944-457: The tyrannosaurids. While tyrannosaurids had small arms and large, powerful heads, megaraptorans had large arms, giant claws, and relatively weak jaws. The skull of a newly discovered juvenile specimen of Megaraptor , published in 2014, supported this hypothesis due to its similarities to the skull of basal tyrannosauroids such as Dilong . Nevertheless, megaraptorans still retained many similarities to carcharodontosaurians such as Neovenator , so
4012-432: The ulna and claws which are not present in the basal megaraptoran Fukuiraptor . No megaraptoran fossil is known to preserve a complete skull, although skull material is known for several taxa. Aerosteon , Megaraptor , Orkoraptor , and Murusraptor preserve several bones of the rear part of the skull, lower jaws are known from Australovenator , and a juvenile specimen of Megaraptor described in 2014 preserved much of
4080-411: The ulna called the lateral tuberosity, which is perpendicular to the blade of the olecranon. As a result, the ulna of megaraptorids is T-shaped in cross section, with three prongs formed by the forward-projection anterior process, the outwards-projecting lateral tuberosity, and the backwards-projecting olecranon process. These adaptations are absent in the most basal megaraptoran, Fukuiraptor . The radius
4148-458: The uncertainty behind their classification was not fully resolved. The cladogram below illustrates the results of a study which supports the Novas et al. (2013) hypothesis that megaraptorans are derived tyrannosauroids. This study was Porfiri et al. (2014), which described the juvenile Megaraptor specimen. Gualicho , Murusraptor , and Tratayenia were not yet described when this study
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#17327806102524216-623: Was a spinosauroid . The same year, Orkoraptor was described as an unusual giant coelurosaurian with some similarities with the much smaller compsognathids. Aerosteon was considered a relative of Allosaurus in its description less than a year later, while Australovenator was considered to be the sister taxon to Carcharodontosauridae. This influx of new data in the late 2000s led to several major reanalyses of basal tetanuran phylogenetics, with interesting implications for these taxa. A study by Roger Benson, Matt Carrano & Steve Brusatte in 2010 found that Allosauroidea (or Carnosauria , as it
4284-474: Was about 4.2 meters (13.8 feet) in length, to the 9 meter (30 feet) long Aerosteon , the 9 to 10 meter (30 to 33 feet) long Maip and the 12.8 meter (42 foot) long Bahariasaurus , if it is a member. Most megaraptorans are known from very fragmentary remains, although certain characteristics can be identified in multiple members of the clade. At least some megaraptorans, such as Murusraptor and Aerosteon , had extensively pneumatic bones (most noticeably
4352-529: Was conducted by Phil Bell, Steve Salisbury et al., which accompanied the description of an unnamed megaraptorid (referred to by the public media as "Lightning Claw," and possibly synonymous with Rapator ) from opal fields southwest of Lightning Ridge, Australia. This supports an Asian origin of Megaraptora in the latest Jurassic (150–135 Ma), an Early Cretaceous (130–121 Ma) divergence of the Gondwanan lineage leading to Megaraptoridae, and an Australian root for
4420-422: Was present a bit lower, between the preacetabular blade and pubic peduncle. This concavity, known as the cuppedicus (or preacetabular) fossa, was rimmed by a prominent shelf on the inner face of the ilium. This trait is also known in various coelurosaurs, Chilantaisaurus , and probably Neovenator . The postacetabular blade, on the other hand, lacks a large concavity. In non-coelurosaurian tetanurans, this portion of
4488-504: Was sometimes called) included a major subdivision known as Carcharodontosauria, which was split into the Carcharodontosauridae and a newly named family: Neovenatoridae . Neovenatorids, as formulated by these authors, contained Neovenator , Chilantaisaurus , and a newly named clade: Megaraptora. Megaraptora contained Megaraptor , Fukuiraptor , Orkoraptor , Aerosteon , and Australovenator . These genera were allied with
4556-446: Was undertaken. Sinraptor Allosaurus [REDACTED] Compsognathidae [REDACTED] Maniraptoriformes [REDACTED] Dilong Santanaraptor Xiongguanlong Tyrannosauridae [REDACTED] Fukuiraptor Eotyrannus Orkoraptor [REDACTED] Aerosteon Megaraptor In 2016, Novas and his colleagues published a study of megaraptoran hand anatomy, in an attempt to help settle
4624-473: Was very similar to that of Allosaurus and indicated that it likely would have preyed upon medium-sized dinosaurs such as stegosaurs by using its blade-like teeth to inflict massive, fatal wounds. Sinraptor hepingensis , formerly referred to Yangchuanosaurus , is a second species referred to this genus. However, the identity of this species within Sinraptor is questioned by other paleontologists, and
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