Pronunciation: OOG-ro-SOR-us
Meaning: Ugly lizard
Author/s: Cobabe and Fastovsky (1987)
Synonyms: None known
First Discovery: Montana, USA
Discovery Chart Position: #331
Ugrosaurus olsoni
Ugrosaurus was discovered at Maloney Hill in Montana's Hell Creek Formation by David Fastovsky in 1983, excavated with the help of J.H. Hutchison and L. Zhexi, and identified as the property of a chasmosaurine ceratopsid, of which Hell Creek already had three in Torosaurus, Nedoceratops and Triceratops. Its meagre fossils, including a vertebra and a partial snout with an unusually robust boss where a chasmosaurine nose horn would normally be, sports some features in common with Torosaurus and some in common with Nedoceratops . However, all of its characteristics fall within the accepted variation range of Triceratops, apparently, so that's where Catherine Forster assigned Ugrosaurus, as Triceratops sp., in 1993.
(Olsen's ugly lizard)Etymology
Ugrosaurus is derived from the Scandinavian "ugro" (ugly) and the Greek "sauros" (lizard), referring to the rough and gnarly surface texture of its bones.The species epithet, olsoni, honours Norman Olson, on whose ranch the specimen was found.
Discovery
The remains of Ugrosaurus were discovered at "Dave's Nose" (Maloney Hill) in the Hell Creek Formation, Garfield County, Montana, USA, by David Fastovsky during a field trip led by W.A. Clemens Jnr. in the summer of 1983.
The holotype (UCMP 128561) is a badly-weathered partial snout, a vertebra, and some unidentified skull and frill fragments.
















