Nodocephalosaurus

Nodocephalosaurus (meaning "knob headed lizard") is a monospecific genus of ankylosaurid dinosaur from New Mexico that lived during the Late Cretaceous (late Campanian to early Maastrichtian stage, 73.49 to 72 Ma) in what is now the De-na-zin member of the Kirtland Formation. The type and only species, Nodocephalosaurus kirtlandensis, is known only from a partial skull. It was named in 1999 by Robert M. Sullivan. Nodocephalosaurus has an estimated length of 4.5 metres (15 feet) and weight of 1.5 tonnes (3,306 lbs). It is closely related and shares similar cranial anatomy to Akainacephalus.

==Discovery and naming== left|thumb|Location and stratigraphy of the Kirtland Formation. In 1995, a partial skull of an ankylosaur was discovered weathering out of a grey mudstone a few hundred metres west of a new Parasaurolophus site in the De-na-zin member of the Kirtland Formation, New Mexico. Robert M. Sullivan and Thomas E. Williamson left the partial skull in the field due to the apparent fragmentary nature of the skull and time constraints. A year later, the skull was obtained from the site by Sullivan with the help of Kesler Randall. The specimen was subsequently described in 1999 by Robert M. Sullivan. The holotype specimen, SMP VP-900 , consists of an incomplete skull and associated cranial fragments. The holotype specimen is currently housed at the State Museum of Pennsylvania, Harrisburg.