Alectrosaurus olseni Gilmore 1933

Holtz, T. R., 2001, The phylogeny and taxonomy of the Tyrannosauridae, Mesozoic Vertebrate Life, Bloomington: Indiana University Press, pp. 64-83 : 68

Alectrosaurus olseni Gilmore 1933 :

Atyrannosaurid from the Iren Dabasu Formation of Inner Mongolia (People's Repubiic of China) and the Bayn Shire Formation of Mongolia, units of uncertain Late Cretaceous age (most probably younger than Cenomanian, and possibly as young as Campanian: Currie and Eberth 1993). Forelimb elements in Gilmore's type material have since proven to come from a therizinosauroid ( Mader and Bradley 1989). The type specimen from China is drfficult to diagnose relative to other tyrannosaurids: however, material from the Mongolian Republic referred to this taxon by Perle (1977) is more complete. This material indicates that the skull was long and low and that the premaxilla contained Aublysodon-like teeth. The skull is generally plesiomorphic relative to other tyrannosaurids, but Currie (in press) documents the following synapomorphy:78.2 Cranialmost 2 to 3 maxillary teeth incisiform. This material is currently under review and Currie (in press) states that the postcranium demonstrates additional (undescribed) diagnostic features. Additional study may indicate that the Mongolian material may not be referable to Alectrosaurus olseni ( Mader and Bradley 1989)..