Erlikosaurus

Live reconstruction of Erlikosaurus with primitive feathers as they were detected in Beipiaosaurus.

• Ömnögov (Mongolia)

• Erlikosaurus andrewsi

Erlikosaurus is a genus theropod dinosaur from the family of Therizinosauridae. Fossils of the animal, consisting of a well-preserved skull and partial skeleton preserved remaining were found in about 100 to 84 million years old sedimentary rocks of Mongolia.

Description

The skull of Erlikosaurus is the best-preserved skull of all Therizinosaurier. The skull was long, low and highly pneumatized. The nostrils were large. The cranial bones, especially before the eye region, and the skull were thin. The premaxilla was formed into a wide, toothless beak, which may have been occupied with outside horn. The nasal extension of the premaxilla was narrow and long, the subnasale extension shortly.

The maxilla was the rear and lower boundary of the external nasal openings. It contributed to the region below the lower cranial window still 24 small, uniform teeth. They were straight and narrow, pointed and laterally flattened. With the exception of five middle- they were close together. The crowns were cut front and back, the roots cylindrical.

The toothless in the front of the lower jaw was flat, the front end pointed downward, as in all other known mandible of Therizinosaurier. Each half of the mandible had 31 teeth, similar to those of the upper jaw. The first five were larger and had a greater distance from each other. The rear sat close together. The lip -side surface of the posterior teeth was convex. All the teeth of the lower jaw had cylindrical roots and sawn edges.

It is considered likely that Erlikosaurus had a beak.

Other skeletal

From the rest of the skeleton only a few parts are known. They also show that the skull was small in comparison to the body for a theropod. The cervical vertebrae were large and elongated. The ribs of the cervical spine were grown together with the vertebrae.

The Phalangenformel for the foot is 2,3,4,5,0. So Erlikosaurus had four toes and not the tridaktylen ( three-toed ) feet of other theropods. The first toe was the shortest, the second and the third largest and the same length. The fourth was slimmer than any other. The Fußkrallen were large, curved and strongly flattened perpendicular to the longitudinal body axis.