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68

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Oviraptorosauria - "The Egg Snatchers"
   Oviraptors are some of the strangest-looking theropods.  They were a very rare group of maniraptorans that are well represented by excellent fossil from the Cretaceous period of Mongolia and North America which were connected, as the supercontinent Laurasia the Cretaceous period.  Some of the most well-preserved specimens of dinosaurs ever found are oviraptors. Oviraptors were once considered to be ornithomimid dinosaurs, but are now placed within the clade Maniraptora.
   They ranged in size from small to moderately large.  All were bipedal and ran on the hind legs. Their most distinguishing characteristic us a toothless jaw which formed a massive beak. Their jaws were well-muscled and adept at crushing. They are distinguished from the toothless ornithomimosaurs by the development of a massive beak and the highly specific in configuration and structure of the lower jaw with the characteristic articular joint.
   The skull provides hints at their possible lifestyle.  They were definitely not carnivores as they had no teeth no cut meat and they were probably not herbivores, but they may have eaten mollusks such as clams that lived in the water nearby.
    The name "oviraptor" (egg snatcher) is a misnomer; their jaws are not useful for eating eggs, but for crushing very hard food. Oviraptors were originally thought to eat eggs because a skeleton was found near a nest that was presumed to be that of the ubiquitous Protoceratops, a ceratopsian dinosaur. A recent discovery found an oviraptor embryo inside one of those eggs, so actually the oviraptor was by its own nest.  More expeditions have found oviraptor skeletons on top of nests.  These devoted parents apparently died in sudden sandstorms while guarding their nests.  Just recently, one of the most amazing fossils ever found was announced - an Oviraptor skeleton preserved brooding a clutch of eggs, just like a bird does. This provides excellent evidence of bird-like behavior already present in the close relatives of birds, and hints that these animals may have been endothermic (brooding keeps eggs warm).
Caudipteryx zoui  - 140 MYA
Liaoning Province, China.  3 feet long
Caudipteryx was a turkey-sized dinosaur.  It had short forelimbs, large eyes and long, sharp, spiked teeth. Quick and agile, it had long slender legs. The most prominent feature of Caudipteryx had to be its tail, which was covered with 6-inch-long tail feathers. The feather fossils show bands of dark and light that may have been color, giving us an idea of how Caudipteryx looked. It was unable to fly.
 

Incisivosaurus gauthieri  - 120 MYA
   Unlike the other oviraptors, Incisivosaurus had a mouth full of teeth. At the very front of the mouth was a pair of enormous gnawing incisors, similar to the “buckteeth” found in mice and beavers. These bizarre teeth have given rise to countless absurd descriptions of Incisivosaurus, from “the bucktoothed oviraptorid” to “the rabbitosaurus”.
Avimimus portentosus - 95 MYA
Mongolia, China.  5 feet long
Avimimus looked so much like a bird that its name literally means that it imitates a bird.  It looks like a large reptilian roadrunner.  Small ridges on its forearm that could be anchor points for feather shafts. Since it descended from Caudipteryx, scientists have concluded that it had feathers too.
Chirostenotes pergracilis - 70 MYA
Alberta Province, Canada - 6 feet long
This little dinosaur was primarily a carnivore, but may have been omnivorous to some extent. The diet of Chirostenotes largely consisted of small game such as lizards and fish. It may have also eaten eggs.
Rinchens mongoliensis - 70 MYA
Mongolia, China - 8 feet long
Rinchenia had the tallest head crest of any oviraptorid. In recent studies of Oviraptors, it appears that each individual would have had a different crest shape and size. North American members of this family discovered to date are considerably larger than their Asian cousins.
Nomingia gobiensis - 68 MYA
Gobi Desert - 3 feet long.
This 1995 discovery was extremely important as Nomingia  is the first classic dinosaur known to have possessed a pygostyle, a bone long considered unique to birds.  This little dinosaur was just about ready to fly! Well, it was at least on its way to becoming a bird. Nomingia is a good example of the term "missing link".
Oviraptor philocerataops - 67 MYA
 

Other Speices

  Microvenator celer Ostrom, 1970
Microvenator is based on a partial postcranial skeleton discovered in the 1930s that was originally associated with large teeth.Thinking these teeth belonged to the skeleton, Barnum Brown informally named the specimen "Megadontosaurus".  The teeth later turned out to belong to a larger theropod, Deinonychus, and the skeleton, named Microvenator, is now known to belong to a small basal relative of the oviraptorids of Montana
  Omnivoropteryx sinousaorum Czerkas and Ji, 2002
mid Barremian-early Aptian (EK) of China
Well...it seems to be a possibly flying critter with a Caudipteryx-like head.  It's known from most of a skeleton, found with possible remains of Cryptovolans, another possible flyer, this time a dromaeosaurid.  The animal, as the name suggests, is interpreted as an omnivore, based on the skull.
  "Thecospondylus" daviesi (N.D.) Seeley, 1888
Barremian (EK) of England
Also known as Thecocoelurus, this taxon, based on a cervical, does not pertain to the much larger Thecospondylus, but instead appears to be an oviraptorosaurian, possibly related to the caenagnathids.  It was rather large, on the order of 7 meters long.
  Heyuannia huangi Lu, 2002
Maastrichtian (LK) of China
Known from multiple remains from at least five individuals, this animal inspired some interesting press in dinosaur paleo circles a while back when it was suggested that reproductive organs were preserved with one individual.  It seems to be rather large for an oviraptorid, and the type is an excellent partially-articulated skeleton with a partial skull.
  Citipati osmolskae Clark, Norell, and Barsbold, 2001
early Campanian (LK) of Mongolia
Citipati is another new oviraptorid based on good remains, a skeleton and skull; remains from two other individuals are known.
Possibly referable to this genus is specimen GI (SPS) 100/42, an excellent specimen (known for its crested skull) previously referred to Oviraptor, and the subject of most current restorations of "Oviraptor", including those in Gregory Paul's Predatory Dinosaurs of the World
  Nemegtia barsboldi Lü, Tomida, Azuma, Dong, and Lee, 2004
early Maastrichtian (LK) of Mongolia
Described as closest to Citipati osmolskae, this genus is based on at least a skull with a prominent crest that has a nearly vertical rostral margin which is at about a 90-degree angle to the dorsal margin of the skull (this confuses me a bit; if I had to guess, this refers to the skull roof, as otherwise they would have said crest again.  However, this is somewhat self-evident, because a subvertical anterior margin has to be defined as such against some sort of reference).  As you might guess from the name, it comes from the Nemegt Formation.
  "Ingenia" yanshini Barsbold, 1981
early Campanian-early Maastrichtian (LK) of Mongolia
The most unusual feature of this animal is its hands.  It has three clawed fingers, but unlike almost all other theropods, the digits are approximately the same length, with the first as longest, another unique feature.  It was weakly crested, with a low triangle on the snout end.
Recently, it was discovered that Ingenia was preoccupied by a nematode (Gerlach, 1957); a replacement name is in the pipeline, but has not been revealed yet.  Also, the urban legend that it was named after InGen from Jurassic Park, or has something to do with it, is completely false.

 

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