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 and 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 T.plicatospineus and no other known ankylosaurid. In diference to Tumanova, Amtosaurus magnus is retained with reservation.