Ceratopsidae

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Ceratopsids
Conservation status: Fossil
Triceratops skull
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Ornithischia
Suborder: Marginocephalia
Superfamily: Ceratopsia
Family: Ceratopsidae
Marsh, 1890
Genera
See text.

Ceratopsids, or members of the Ceratopsidae (or Ceratopidae), are a diverse group of marginocephalian dinosaurs like Triceratops and Styracosaurus. They were quadrupedal, herbivores from the Upper Cretaceous of Western North America and are characterized by beaks, shearing teeth in the back of the jaw, and elaborate horns and frills. The group is divided into two subfamilies. The Ceratopsinae or Chasmosaurinae are characterized by long smoother frills and eyebrow horns. The Centrosaurinae had well-developed nasal horns or nasal bosses, shorter frills, and elaborate spines on the frill.

These horns and frills show remarkable variation and are the principle means by which the various species have been recognized. Their purpose is not entirely clear. Defense against predators is one obvious purpose, but they may also have been used in displays, or for intraspecific combat. The massive bosses on the skulls of Pachyrhinosaurus and Achelosaurus resemble those formed by the base of the horns in modern musk oxen, suggesting that they may have butted heads. Centrosaurs have frequently been found in massive bone beds with few other species present, this suggests that the animals might have lived in large herds.

Taxonmy

  • Superfamly Ceratopsia
  • FAMILY CERATOPSIDAE
    • Subfamily Centrosaurinae
      • Avaceratops
      • Tribe Centrosaurini
        • Monoclonius
          • Brachyceratops
            • Centrosaurus
              • Styracosaurus
      • Tribe Pachyrhinosaurini
        • Einiosaurus
          • Achelousaurus
            • Pachyrhinosaurus
    • Subfamily Ceratopsinae
      • ? Ceratops
      • Pentaceratops
        • Chasmosaurus
      • Anchiceratops