[D] Nemegtosaurus mongoliensis [Su] [sG] [T]
Cretaceous Late ?Campanian Maastrichtian
Saurischia Sauropodomorpha Sauropoda Diplodocidae Dicraeosaurinae
Nemegt Formation, Gobi Desert, Omnogov, Mongolia
Genus - Typespecies - Skull
Nemegtosaurus is based on an isolated skull, (Holotype ZPAL MgD-I/9) the most complete of the known Late Cretaceous skulls. The dorsal processes of the maxillae and the rostral part of the nasals as well as the front of the braincase and a number of bones of the palate, have been damaged. Otherwise, it is nearly complete. The holotype was discovered by during the Polish-Mongolian Expedition.
Nemegtosaurus mongoliensis has a lightly built but elongate skull with slender, peg-like teeth as Diplodocus at the front of the jaws. The dental formula is 4:8/13. The lower jaw of Nemegtosaurus differs from that of other diplodocids in the length of the dentary. The nasal does not contact the maxilla, but the squamosal reaches the quadratojugal. The shape and size of the external naris is completely unknown.
Hunt et al., (1994) assigned Nemegtosaurus and Quaesitosaurus to the family Dicraeosaurinae.