New leptoceratopsids from the Upper Cretaceous of Alberta, Canada. 2012. Cret. Res.:35: 69-80.
Abstract: Two new leptoceratopsid neoceratopsians are described based on partial dentaries collected from the Dinosaur Park (Campanian) and Milk River (Santonian) formations of Alberta. The new Campanian taxon has a unique dentary tooth shape not shared by other leptoceratopsid taxa, which has implications for the evolution of the Leptoceratopsidae. The Santonian specimen represents the oldest known leptoceratopsid (w83 Ma), and probably represents the smallest adult-sized ceratopsian known from North America.
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