Nomingia
Live reconstruction of Nomingia gobiensis
- Mongolia ( Nemegt Formation)
- Nomingia gobiensis
Nomingia was a theropod dinosaur from the group of Oviraptorosauria from the Upper Cretaceous of Mongolia. This genus is known from a partial skeleton, based on which the only way Nomingia gobiensis was first described in 2000. There was an estimated 1.8 meters long, bipedal running animal with a short tail. Although cranial bones are not known, it is assumed that Nomingia like other Oviraptorosaurier had a deep, edentulous jaw, which was formed into a beak. Presumably it was a plant or omnivores.
The systematic position within the Oviraptorosauria is not secured. Features on the bowel and ischial show, however, that the genus could possibly be classified within the Caenagnathidae.
Fund and naming
The date the only Fund ( holotype; catalog number GIN 100/119 ) was made Bajanchongor in 1994 by a Mongolian -Japanese expedition in Bugin Tsav in Mongolian aimag. From the same site, the remains of Oviraptoriden Ajancingenia come. Stratigraphic origin of the fossils from sedimentary rocks of the Bugin Tsav Beds belonging to the Nemegt lineup and about 71-69 million years old are (early Maastrichtian ). The spine of the partial skeleton is completely preserved from the last two cervical vertebrae to the tail end in the anatomical composite, thus 13 Präsakralwirbel ( vertebrae and 1-3 neck vertebrae), 5 sacral vertebrae ( sacral vertebrae ) and 24 caudal vertebrae, including the most chevron bones known. Furthermore, there is a frame of 10 fragmentary ribs, some Gastralia, the entire pelvic region, the left femur and the tibia and fibula of both legs legs. The name is derived from Nomingia Nomingiin Gobi, a part of the Gobi desert near the locality. The Artepitheth gobiensis derived from the Gobi desert itself.
Features
The most important discovered in Nomingia feature is the fusion of the last five vertebrae of the tail. Known as pygostyle structure is otherwise used only in birds, although 2008 Similicaudipteryx another Oviraptorosaurier been described with a pygostyle. Probably the pygostyle has in birds and Oviraptorosauriern convergent developed ( independently ). In birds, the pygostyle used to support the long tail feathers, which is why the describer suspect also Nomingia might have worn a fan of long tail feathers. Springs have not been preserved in Nomingia, but nevertheless it seems very likely due to the Pygostyls that this Oviraptorosaurier was feathered.
The tail was very short and consisted of only 24 caudal vertebrae, so Nomingia had the second shortest tail of all known theropods - only Caudipteryx dismissed with only 22 caudal vertebrae an even shorter tail on. The chevron bones were wide and ran along the whole underside of the tail except the pygostyle. Other unique features ( autapomorphies ) of Nomingia showed at the pelvic bone; so the pubic bone ( pubis ) for example, was inclined at 20 degrees to the vertical. Other features shared with other Nomingia Oviraptorosauriern what the classification within this group justifies ( synapomorphies ), such as the large hypapophyses three vertebrae at the junction between the back and neck as well as the pneumatized ( hollowed ) anterior caudal vertebrae.