Tyrannosaurus regina sp. nov. (Morphotype III)
Etymology: Tyrant lizard queen.
Holotype: USNM 555000
Referred specimens: exBHI 3033, MOR 980, LACM 23485, LL 12823, TMP 81.6.1, LACM 23845 .
Age and stratigraphy: Latest Maastrichtian, upper and possibly middle Hell Creek and Lance, Ferris, Denver, Frenchman, Willow Creek, Scollard.
Diagnosis: Generally gracile with an adult femur-length/ circumference ratio over 2.4, usually one slender anterior incisiform dentary tooth.
Geographic distribution: Montana, Colorado, Dakotas, Wyoming, Alberta, Saskatchewan.