Leptoceratopsidae
Historical reconstruction of skeletal Montanoceratops (1942 )
- North America
The Leptoceratopsidae (also Leptoceratopidae ) are a taxon ( a systematic group) of the dinosaurs from the group of ceratopsians. They include some of the smaller living in the Upper Cretaceous in what is now North America animals.
The animals in this group were relatively small dinosaur. As with all Ceratopsia the snout from the Rostralknochen and the Praedentale was formed. On the neck there was the typical for the more developed Ceratopsia neck shield. The teeth were aligned to a plant-based diet, in contrast to the tooth batteries Ceratopsidae but they were just built.
The systematics within the Ceratopsia is controversial. After phylogenetic studies Leptoceratops and Montanoceratops form a well-defined clade and the "core" of Leptoceratopsidae. These animals were previously classified in the Protoceratopsidae, but today managed as a separate family Leptoceratopsidae. According to the definition of P. Makovicky the Leptoceratopsidae include all taxa that are more closely related Leptoceratops than Triceratops.
The following genera are possibly this:
- Leptoceratops
- Montanoceratops
- Prenoceratops
- Gryphoceratops
- Unescopceratops
All these genera lived in the Upper Cretaceous ( Campanian and Maastrichtian ) in North America today. The membership of the Asian forms Bainoceratops and Udanoceratops is controversial - some features speak for one belonging to the Protoceratopsidae - as well as the some poorly preserved taxa ( Asiaceratops and Serendipaceratops ). The 2007 discovered genus Cerasinops may be the sister taxon of Leptoceratopsidae.
The external system is controversial. According to P. Makovicky the Leptoceratopsidae form the sister taxon of a group of Protoceratopsidae and Ceratopsoidea ( Zuniceratops and Ceratopsidae ). According to You et al. however, are more closely related to the Ceratopsoidea than with the Protoceratopsidae the Leptoceratopsidae. Paläobiogeographisch the second option would be more plausible, since it would result in a clade occurring only in North America, facing the Asian Protoceratopsidae.