Pyroraptor is a genus of dromaeosaurid dinosaur from the late Cretaceous Period of France. It is known from a single specimen.
Pyroraptor was a dromaeosaurid, a small, bird-like predatory theropod that possessed enlarged curved, slashing claws on the second toe of each foot. Each of these claws were 6.5 centimeters (2.5 in) long. The only identified specimen was found in 1992 in the south of France, in Provence, and is known only from a few bones, named Pyroraptor olympius by Allain and Taquet in 2000. The name means "Olympic fire thief", because its remains were discovered after a forest fire. The type specimen consists of the distinctive foot claws, as well as fossilized teeth, arm and back bones. It lived during the late Campanian and early Maastrichtian faunal stages of the Late Cretaceous, approximately 70.6 million years ago.Pyroraptor was featured in one episode of the television program Dinosaur Planet, in which an individual Pyroraptor named "Pod" is swept onto an island dominated by dwarf members of familiar dinosaur families.
Dromaeosauridae was first defined as a clade by Paul Sereno in 1998, as the most inclusive natural group containing Dromaeosaurus but not Troodon, Ornithomimus or Passer. The various "subfamilies" have also been re-defined as clades, usually defined as all species closer to the groups namesake than to Dromaeosaurus or any namesakes of other sub-clades (for example, Makovicky defined the clade Unenlagiinae as all dromaeosaurids closer to Unenlagia than to Velociraptor). The Microraptoria is the only dromaeosaurid sub-clade not converted from a subfamily. Senter and colleagues expressly coined the name without the subfamily suffix -inae to avoid perceived issues with erecting a traditional family-group taxon, should the group be found to lie outside dromaeosauridae proper. Sereno offered a revised definition of the sub-group containing Microraptor to ensure that it would fall within Dromaeosauridae, and erected the subfamily Microraptorinae, attributing it to Senter et al., though this usage has only appeared on his online TaxonSearch database and has not been formally published.
The cladogram below follows a 2009 analysis by paleontologists Nicholas Longrich and Philip J. Currie.
Dromaeosaurs are diagnosed by the following features; short T-shaped frontals that form the rostral boundary of the supratemporal fenestra; a caudolateral overhanging shelf of the squamosal; a lateral process of the quadrate that contacts the quadratojugal; raised, stalked, parapophyses on the dorsal vertebrae, a modified pedal digit II; chevrons and prezygapophyses of the caudal vertebrae elongate and spanning several vertebrae; the presence of a subglenoid fossa on the coracoid.Caenagnathidae ("recent jaws," as derived from Greek kainos and gnathos) is a family of bird-like maniraptoran theropod dinosaurs within the clade Oviraptorosauria, first coined as an order of advanced flightless birds by Charles Hazelius Sternberg in 1940. While more advanced than earlier oviraptorosaurs like Caudipteryx, caenagnathids were fairly primitive compared with their close relatives the oviraptorids, though this by no means reduces the distinct variation and unique nature of the group. Whereas oviraptorids had highly shortened snouts, caenagnathid jaws were long and shallow with an elongated dentary and extended symphysis. Indeed, the jaw of a caenagnathid is its most distinctive feature, historically, whose surface and internal structure is distinct from that of other dinosaurs, including oviraptorids. Caenagnathids are best known for their cranial anatomy, but the earliest forms are known from their postcrania alone, and include such novel features as a fused ankle (as also seen in similar and possibly related Avimimus portentosus), an extremely short tail, possibly with a pygostyle as in Nomingia gobiensis, and with exceptionally slender and long legs, giving them a gracile, long-legged appearance that may have resembled some of the smaller ratite birds, such as the emu.
The name Caenagnathus (and hence Caenagnathidae) means "recent jaws"--when first discovered, it was thought that caenagnathids were close relatives of paleognath birds (such as the ostrich) based on features of the lower jaw. Since it would be unusual to find a recent group of birds in the Cretaceous, the name "recent jaws" was applied. Most paleontologists, however, now think that the birdlike features of the jaw were acquired convergently with modern birds.The family Caenagnathidae, together with its sister group the Oviraptoridae, comprises the superfamily Caenagnathoidea. In phylogenetic taxonomy, the clade Caenagnathidae is defined as the most inclusive group containing Chirostenotes pergracilis but not Oviraptor philoceratops. While in the past twenty years, only about two to six species were commonly recognized as belonging to the Caenagnathidae, currently that number may be much greater, with new discoveries and theories about older species that may inflate this number to up to ten. Much of this historical difference centers on the first caenagnathid to be described, Chirostenotes pergracilis. Due to the poor preservation of most caenagnathid remains and resulting misidentifications, different bones and different specimens of Chirostenotes have historically been assigned to a number of different species. For example, the feet of one species, named Macrophalangia canadensis,[6] were known from the same region from which Chirostenotes pergracilis was recovered, but the discovery of a new specimen with both hands and feet preserved provided the support to combine them, while the later discovery of a partial skull with hands and feet suggested that Chirostenotes and Caenagnathus were the same animal. While Caenagnathus collinsi is today considered to be a junior synonym of Chirostenotes pergracilis by most researchers, it was the first for which a family was named, so while the genus name Caenagnathus is no longer in use, the family name Caenagnathidae remains valid due to its inclusion of Caenagnathus.
Today, Caenagnathidae usually contains six species in three genera. However, a few paleontologists consider Elmisaurus elegans to be a junior synonym of Chirostenotes sternbergi, as they both occur in the same North American locality, far from the Asian species Elmisaurus rarus . The genus Caenagnathasia martinsoni was originally placed in this family, but it is probably more primitive, lying outside both Caenagnathidae and Oviraptoridae within the superfamily Caenagnathoidea. Additionally, Maryańska, Osmólska, and Wołsan considered the oviraptorosaur with a pygostyle, Nomingia gobiensis, a member of this family.
Caenagnathidae includes -
Chirostenotes pergracilis, the first known caenagnathid, described initially from two hands and a partial lower arm. Many subsequently named species have been referred to this species, including a single foot named Macrophalangia canadensis[6], adding to the known fossil material.
Chirostenotes sternbergi, a more gracile caenagnathid. Some consider Elmisaurus elegans to be the same animal, as both are smaller and more slender than Chirostenotes pergracilis. It is also possible that this species represents a different gender of the larger C. pergracilis specimens.
Chirostenotes sp., a possible new species, has been identified from part of a lower jaw found in Montana, but not named.
Elmisaurus rarus, the only known Asian caenagnathid (excluding Caenagnathasia martinsoni), is known only from elements of the foot.
Elmisaurus elegans, a smaller Canadian species originally described as a species of Ornithomimus. It may be the same species as Chirostenotes sternbergi, as noted above.
The "Triebold caenagnathid", a possible new species or genus collected by Triebold Paleontology of South Dakota, known from two excellently preserved partial specimens acquired by the Carnegie Museums of Pittsburgh. An apparently giant species with a well preserved skull and evidence of an oviraptorid-like crest, it is currently awaiting a published description. Oviraptoridae is a group of bird-like maniraptoran dinosaurs. They are currently known from Mongolia and China, although there is an unpublished report from Montana. These animals were small, measuring up to 2 m long in most cases. Definitive oviraptorids first appeared in the Cenomanian stage of the late Cretaceous Period, although the possible oviraptorid Microvenator is known from the Aptian stage of the Early Cretaceous Period. The family became extinct at the end of the Maastrichtian stage.
Hagryphus giganteus, discovered most recently, is a fairly large and over-assuming yet seldom mentioned species from Upper Cretaceous beds in Utah, USA (and is roughly the same age as Chirostenotes pergacilis
The most characteristic feature of this group is the skull structure. Oviraptorids had short snouts and very deep mandibles. Some taxa (Oviraptor, Citipati, Rinchenia) had a midline crest on top of the skull, resembling that of a cassowary. Other distinguishing characters include a bony spike intruding on the mandibular fenestra, nostrils placed very high and far back on the snout, an extremely thin bony bar beneath the eye, and highly pneumatized skull bones. Like their relatives the caenagnathids, the jaws were edentulous (with no teeth), having instead two small bony projections on the top jaw.
Oviraptoridae includes -
Gigantoraptor erlianensis, the largest oviraptorid, at 8 meters in length.
Oviraptor philoceratops, from the Late Cretaceous of Mongolia. Found in 1924, it has a longer snout and seemingly extensive crest on its head. Most illustrations of it are actually based on Citipati sp..
Rinchenia mongoliensis was originally called Oviraptor mongoliensis. It had a very high crest on the center of its head, and is from the Late Cretaceous of Mongolia as well.
Nemegtomaia barsboldi, originally named Nemegtia and once assigned to "Ingenia", is probably a close relative of Citipati, known from excellent skull material.
Citipati osmolskae was named based on several well-known specimens, including nesting adults, eggs, and an embryo. It had an anteriorly-placed crest and lived at the same time and place as Oviraptor.
Citipati sp., a specimen recently referred to the genus Citipati, was found in the 1980s and previously thought to be Oviraptor. It had a forward-sloping cassowary-like crest.
Conchoraptor gracilis is a small crestless form with a slender second toe. Many specimens have been referred to it, but there have been no detailed studies showing exactly which ones are correctly referred.
Khaan mckennai is another taxon that closely resembles Conchoraptor, but has a reduced third finger. It lived alongside Citipati.
"Ingenia" yanshini has also had a lot of material referred to it that probably doesn't belong. It was contemporaneous with Conchoraptor, and work needs to be done separating their remains from each other. "Ingenia"s hand is distinguished by a very large first finger and reduced second and third fingers. The name "Ingenia" a crimeajewel insignia ,is preoccupied and will be replaced in the near future.
Heyuannia huangi is the first named oviraptorid from China and resembles Ingenia closely, but is distinguished by having more hip vertebrae and the first finger fused with the wrist.
Other possible oviraptorids include Nomingia gobienisis, Shixinggia oblita, and the early Microvenator celer. All three have been suggested to be oviraptorids, caenagnathids, or more primitive than either group.
The eating habits of these animals are not fully known, but some appear to have been at least partially carnivorous, eating small vertebrates such as lizards and juvenile or nestling dinosaurs. Evidence for this comes from a lizard skeleton preserved in the body cavity of the type specimen of Oviraptor and two hatchling Byronosaurus skulls found in a Citipati nest. Some scientists have also suggested that some oviraptorids included of plant material, eggs, and/or mollusks in their diet.
Originally, oviraptorids were thought to be specialized egg raiders, based on a Mongolian find showing Oviraptor on top of a nest erroneously attributed to the ceratopsian dinosaur Protoceratops. However, discoveries in the 1990s, including Citipati specimens clearly brooding (rather than predating) the same types of nests, and a Citipati embryo inside the same type of egg preserved in these nests, showed that the "specialized egg thief" idea was incorrect, though oviraptorids may have eaten eggs as part of an omnivorous diet.
Although fossilized dinosaur eggs are generally rare, oviraptorid eggs are relatively well known. Several oviraptorid nests, eggs, and embryos are known, mostly uncovered in the Gobi Desert. Some specimens of the Oviraptor philoceratops and Citipati osmolskae have been found in brooding positions. described in 1999, All of the nesting specimens are situated on top of egg clutches, with their limbs spread symmetrically on each side of the nest, front limbs covering the nest perimeter. This brooding posture is found today only in birds and supports a behavioral link between birds and theropod dinosaurs.
Oviraptorid eggs are shaped like elongated ovals (elongatoolithid) and resemble the eggs of ratite birds (such as ostriches) in texture and shell structure. In the nest, eggs are typically found in pairs and arranged in concentric circles of up to three layers, with complete clutches consisting of as many of 22 eggs in some species. The eggs of Citipati are the largest known definitive oviraptorid eggs, at 18 cm. In contrast, eggs associated with Oviraptor are only up to 14 cm long.
Ironically, it was the association with eggs that gave oviraptorids their name (which means 'egg thieves'). The first oviraptorid eggs (of the genus Oviraptor) were found in close proximity to the remains of the ceratopsian dinosaur Protoceratops and it was assumed that the oviraptorids were preying upon the eggs of the ceratopsians. It was not until 1993, when a Citipati embryo was discovered inside an egg of the type assigned to Protoceratops, that the error was corrected. Norell et al., who recognized the embryo as oviraptorid, assigned it to the genus Citipati. The egg containing the embryo was smaller than most known Citipati eggs at only 12 cm, though it was partially eroded and broken into three pieces, making an accurate estimate of its original size difficult.The embryo-bearing egg was otherwise identical to other oviraptorid eggs in shell structure and was found in an isolated nest, again arranged in a circular pattern.
An oviraptorosaurian specimen from China described in 2005 was found to have two unlaid eggs within the pelvic canal. This suggests that, unlike modern crocodilians, oviraptorosaurs did not produce and lay many eggs at the same time. Rather, the eggs were produced within the reproductive organs in pairs, and laid two at a time, with the mother positioned in the center of the nest and rotating in a circle as each pair was laid. This behavior is supported by the fact that the eggs oval shape, with the more narrow end pointing backward from the birth canal, matching their orientation toward the center of the nest after being laid.
The presence of two shelled eggs within the birth canal shows that oviraptorosaurs were intermediate between the reproductive biology of crocodilians and modern birds. Like crocodilians, they had two oviducts. However, crocodilians produce multiple shelled eggs per oviduct at a time, whereas oviraptorosaurs, like birds, produced only one egg per oviduct at a time.
Oviraptorids were probably feathered, since some close relatives were found with feathers preserved (Caudipteryx and possibly Protarchaeopteryx). Another finding pointing to this is the discovery in Nomingia of a pygostyle, a bone that results from the fusion of the last tail vertebrae and is responsible in birds to hold a fan of feathers in the tail. Finally, the arm position of the brooding Citipati would have been far more effective if feathers were present to cover the eggs.
Oviraptoridae is a group of bird-like maniraptoran dinosaurs. They are currently known from Mongolia and China, although there is an unpublished report from Montana. These animals were small, measuring up to 2 m long in most cases. Definitive oviraptorids first appeared in the Cenomanian stage of the late Cretaceous Period, although the possible oviraptorid Microvenator is known from the Aptian stage of the Early Cretaceous Period. The family became extinct at the end of the Maastrichtian stage.
The most characteristic feature of this group is the skull structure. Oviraptorids had short snouts and very deep mandibles. Some taxa (Oviraptor, Citipati, Rinchenia) had a midline crest on top of the skull, resembling that of a cassowary. Other distinguishing characters include a bony spike intruding on the mandibular fenestra, nostrils placed very high and far back on the snout, an extremely thin bony bar beneath the eye, and highly pneumatized skull bones. Like their relatives the caenagnathids, the jaws were edentulous (with no teeth), having instead two small bony projections on the top jaw.
Heyuannia ("Heyuan one") is a genus of oviraptorid dinosaur that lived during the Late Cretaceous Period in China. It was the first oviraptorid found in that country (most lived in neighbouring Mongolia). It had very short arms and digits, and its first digit was reduced.
The type species, Heyuannia huangi, was described by Lü in 2002. Multiple fossils have been found, including one which may retain possible reproductive organs.
Oviraptoridae includes -
Gigantoraptor erlianensis, the largest oviraptorid, at 8 meters in length.
Oviraptor philoceratops, from the Late Cretaceous of Mongolia. Found in 1924, it has a longer snout and seemingly extensive crest on its head. Most illustrations of it are actually based on Citipati sp..
Rinchenia mongoliensis was originally called Oviraptor mongoliensis. It had a very high crest on the center of its head, and is from the Late Cretaceous of Mongolia as well.
Nemegtomaia barsboldi, originally named Nemegtia and once assigned to "Ingenia", is probably a close relative of Citipati, known from excellent skull material.
Citipati osmolskae was named based on several well-known specimens, including nesting adults, eggs, and an embryo. It had an anteriorly-placed crest and lived at the same time and place as Oviraptor.
Citipati sp., a specimen recently referred to the genus Citipati, was found in the 1980s and previously thought to be Oviraptor. It had a forward-sloping cassowary-like crest.
Conchoraptor gracilis is a small crestless form with a slender second toe. Many specimens have been referred to it, but there have been no detailed studies showing exactly which ones are correctly referred.
Khaan mckennai is another taxon that closely resembles Conchoraptor, but has a reduced third finger. It lived alongside Citipati.
"Ingenia" yanshini has also had a lot of material referred to it that probably doesn't belong. It was contemporaneous with Conchoraptor, and work needs to be done separating their remains from each other. "Ingenia"s hand is distinguished by a very large first finger and reduced second and third fingers. The name "Ingenia" is preoccupied and will be replaced in the near future.
Heyuannia huangi is the first named oviraptorid from China and resembles Ingenia closely, but is distinguished by having more hip vertebrae and the first finger fused with the wrist.
Other possible oviraptorids include Nomingia gobienisis, Shixinggia oblita, and the early Microvenator celer. All three have been suggested to be oviraptorids, caenagnathids, or more primitive than either group.
The eating habits of these animals are not fully known, but some appear to have been at least partially carnivorous, eating small vertebrates such as lizards and juvenile or nestling dinosaurs. Evidence for this comes from a lizard skeleton preserved in the body cavity of the type specimen of Oviraptor and two hatchling Byronosaurus skulls found in a Citipati nest. Some scientists have also suggested that some oviraptorids included of plant material, eggs, and/or mollusks in their diet.
Originally, oviraptorids were thought to be specialized egg raiders, based on a Mongolian find showing Oviraptor on top of a nest erroneously attributed to the ceratopsian dinosaur Protoceratops. However, discoveries in the 1990s, including Citipati specimens clearly brooding (rather than predating) the same types of nests, and a Citipati embryo inside the same type of egg preserved in these nests, showed that the "specialized egg thief" idea was incorrect, though oviraptorids may have eaten eggs as part of an omnivorous diet.
Although fossilized dinosaur eggs are generally rare, oviraptorid eggs are relatively well known. Several oviraptorid nests, eggs, and embryos are known, mostly uncovered in the Gobi Desert. Some specimens of the Oviraptor philoceratops and Citipati osmolskae have been found in brooding positions. described in 1999, All of the nesting specimens are situated on top of egg clutches, with their limbs spread symmetrically on each side of the nest, front limbs covering the nest perimeter. This brooding posture is found today only in birds and supports a behavioral link between birds and theropod dinosaurs.
Oviraptorid eggs are shaped like elongated ovals (elongatoolithid) and resemble the eggs of ratite birds (such as ostriches) in texture and shell structure. In the nest, eggs are typically found in pairs and arranged in concentric circles of up to three layers, with complete clutches consisting of as many of 22 eggs in some species. The eggs of Citipati are the largest known definitive oviraptorid eggs, at 18 cm. In contrast, eggs associated with Oviraptor are only up to 14 cm long.
Conchoraptor (meaning "conch plunderer") was an oviraptorid dinosaur from the late Cretaceous Period of what is now Asia. Its name reflects the hypothesis that oviraptorids, rather than preying primarily upon eggs as had been traditionally thought, may have been specialized to feed on mollusks.
Conchoraptor was a small dinosaur, of only 1-2 meters (4-6 feet) in length. Unlike many other oviraptorids, Conchoraptor lacked a head crest, although it did lack teeth, a typical oviraptorid characteristic. Instead of teeth, oviraptorids had powerful beaks, possibly adapted to crushing mollusc shells.
When first discovered in the Nemegt Formation during the 1970s, scientists believed that Conchoraptor was a juvenile Oviraptor and that the animal's missing crest would have begun to grow when the animal reaching sexual maturity. Further study of multiple skeletons showed that Conchoraptor belonged in a new genus.
The type species of this new genus, Conchoraptor gracilis, was described by Barsbold, in 1986. Conchoraptor's hands were a major reason that scientists decided to split it off from Oviraptor. Anatomically the hands seemed to be an evolutionary intermediate between those of "Ingenia" and Oviraptor, making it obvious that this animal was not a member of a known species
Khaan (pronounced Mongol IPA: [χaːŋ], etymology: Derived from the Mongolian for 'lord') was an oviraptorid dinosaur about four feet long that was found in the Djadochta Formation of Mongolia and lived in the Late Cretaceous Period, 70 million years ago.
Khaan did not differ much from other oviraptorids. At first, its remains were assigned to "Ingenia", but the Khaan manual structure differs sufficiently from that of "Ingenia" for it to be assigned to its own genus. Among oviraptorids, it was probably more closely related to Conchoraptor.
Like other oviraptorids, Khaan was probably at least partially a meat eater, feeding on small vertebrates like mammals, lizards and possibly other small dinosaurs. It was also probably feathered.
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