Segnosaurus

Segnosaurus is a genus of herbivorous theropod dinosaur belonging to the Therizinosauridae from the Cretaceous of Mongolia.

In 1973, a Soviet-Mongolian expedition near Amtgay uncovered the fossil of a theropod. In 1974 and 1975 more such remains were discovered, at the same site but also near Khara-Khutul. The type species, Segnosaurus galbinensis, was named and described in 1979 by Dr. Altangerel Perle. The generic name is derived from Latin segnis meaning 'slow' or 'sluggish' and Greek sauros meaning 'lizard', in reference to the stocky build of the hindlimbs. The specific name refers to the Galbin region.

Four specimens were recovered from the Bayan Shireh Formation of the Mongolian People's Republic, in sediments dated between the Cenomanian to Turonian stages. These include the holotype, IGM 100/80, a partial skeleton consisting of a mandible, pelvis, right thighbone, scapulocoracoid, incomplete forelimb and sacral and caudal vertebrae; and the paratypes IGM 100/82 and IGM 100/83, both more fragmentary skeletons also lacking the skulls. Later specimen IGM 100/81 was referred, a foot.