The first small ceratopsian named, Leptoceratops was discovered in 1910 (and described four years later), by Barnum Brown in the Red Deer Valley in Alberta, Canada. The first specimen had a part of its skull missing, however there have been later well-preserved finds by C. M. Sternberg in 1947, including one complete fossil. There has been later material found in 1978 in Bighorn Basin in northern Wyoming. The type species is Leptoceratops gracilis. In 1942, material collected in Montana was named Leptoceratops cerorhynchos but this was later renamed Montanoceratops.