Describer

Kurzanov Tumanova, 1978

Time

Cretaceous Late Cenomanian Turonian

Classification

Ornithischia indet. Nomina Dubia

Diet

Herbivore

Fossilsite

Baynshirenskaya Svita, Antgai Omnogov, Mongolia

Info

Genus - Typespecies

Fragmentary skull

Holotype PIN N 3870/2, [and only know specimen] braincase. [may be hadrosaurid]. Amtosaurus magnus differs from Talarurus plicatospineus in various details and proportions of the basicranial region (Kurzanov Tumanova , 1978; Tumanova, 1987) Maryanska, 1977 regarded these differences as sufficient for specific diagnosis but pointed out details in the pattern of cranial foramina that are also present in Talarurus plicatospineus and no other known ankylosaurid.

Parrish, Jolyon & Paul Barrett, 2004. A reappraisal of the ornithischian dinosaur Amtosaurus magnus (Kurzanov Tumanova, 1978), with comments on the status of Amtosaurus archibaldi (Averianov, 2002). Canadian Journal of Earth Sciences 41 (3): 299-306.

Abstract: A fragmentary braincase from the Baynshirenskaya Svita (Cenomanian–Turonian) of Amtgay, Omnogov, People\\\\\\\'s Republic of Mongolia was described as the holotype specimen of the ankylosaurid dinosaur, Amtosaurus magnus (Kurzanov Tumanova, 1978).

However, the validity of this genus has been questioned by several authors. Recently, a second species, based on a fragmentary specimen consisting of a braincase and partial skull roof, was assigned to Amtosaurus as Amtosaurus archibaldi (Averianov, 2002). Here we re-assess the status of Amtosaurus and of the referred species, Amtosaurus archibaldi.

We conclude that Amtosaurus magnus is a nomen dubium that should be regarded as Ornithischia indeterminate. However, Amtosaurus archibaldi is a valid taxon, characterized by an autapomorphic feature of the skull roof, and we refer this species to the new genus Bissektipelta.