Species: olseni GILMORE, 1933
Etymology: In honor of Everett Olsen.
= Albertosaurus (Alectrosaurus) olseni (GILMORE, 1933) PAUL, 1988
= Albertosaurus olseni (GILMORE, 1933) PAUL, 1988

Holotype: MPC-D100/50

Locality: Baishin-Tsav, Ömnögov Province, Southeastern Mongolia.

Horizon: Bayanshiree Formation.

Biostratigraphy:

Age: Turonian Stage, Upper Gallic Subepoch, Lowermost Gulf Epoch, Middle Cretaceous.

Material: Partial maxilla, nasal, partial left lacrimal, partial left and right quadrate, vomer, jugal porcess of left and right ectopterygoids, partial left and right pterygoid, 3 mid to posterior dorsal vertebrae, 17 contiguous distalmost caudal vertebrae, furculum, left scapulocoracoid, and a left metatarsal III.

Referred material:

MPC-D 100/51; Partial skeleton including right postorbitial, right quadratojugal, right quadrate, partial left ilum, left ischium, and right hind limb, including proximal half of metatarsus and 4 pedal phalanges.

MPC-D102/4: Isolated frontal.