Talarurus (/ˌtæləˈrʊərəs/ TAL-ə-ROOR-əs) is an extinct genus of ankylosaurid dinosaur that lived approximately 90 million years ago during the latter part of the Cretaceous Period in what is now Mongolia. Talarurus was a hippopotamus-sized, heavily built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated 6.0 m (19.7 ft) long. Like other ankylosaurs it had heavy armour and a club on its tail. Along with Tsagantegia, Talarurus is one of the oldest known ankylosaurines from Asia and one of the better-known ankylosaurs from Mongolia
The skull of Talarurus measured approximately 24 centimetres (9.4 in) in length by approximately 22 centimetres (8.7 in) wide, and its body length has been estimated at 3.9 to 6 metres (13 to 20 ft). In 2010, Gregory S. Paul estimated the length at five metres, the weight at two tonnes.[8]
Talarurus was described by Malejev as having had five fingers on the hand and four toes on the foot. However, a four-toed foot was not found in articulation; the mounted foot is a composite and three is the more likely number as all other known ankylosaurids show three toes; earlier reports that Pinacosaurus also possessed four are incorrect.[4] Another presumed diagnostic characteristics: that the osteoderms had a furrowed ornamentation, making for a specially formidable armour, with each plate adorned with additional pleated spines, was also based on a misunderstanding. These were segments of the halfrings protecting the neck, with their typical low keels. The mount has the further peculiarity that it shows Talarurus as built like a hippopotamus, with a barrel-shaped thorax, not with the characteristic ankylosaurid low and wide body type. This was caused by an incorrect positioning of the ribs as if they were appending instead of sticking out sideways; this mistake also prevented a mounting of the wide upper pelvic elements.
Authentic traits of Talarurus include dorsal vertebrae with transversely broad hypapophyses, swellings of the lower front centrum rims. There is a sacral rod of four rear dorsal vertebrae, connected to the true sacrum consisting of four sacrals and a caudo-sacral. The tail club of the mount is rather small.