Dinosaur classification

Dinosaur classification

Encyclopedia
Dinosaur classification began in 1842 when Sir Richard Owen placed Iguanodon
Iguanodon
Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedal hypsilophodontids and the ornithopods' culmination in the duck-billed dinosaurs...

, Megalosaurus
Megalosaurus
Megalosaurus is a genus of large meat-eating theropod dinosaurs of the Middle Jurassic period of Europe...

, and Hylaeosaurus
Hylaeosaurus
Hylaeosaurus is the most obscure of the three animals used by Sir Richard Owen to first define the new group Dinosauria, in 1842. The original specimen, recovered by Gideon Mantell from the Tilgate Forest in the south of England in 1832, now resides in the Natural History Museum of London, where...

in "a distinct tribe or suborder of Saurian Reptiles, for which I would propose the name of Dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

ia." In 1887 and 1888 Harry Seeley
Harry Seeley
Harry Govier Seeley was a British paleontologist.-Career:Seeley was born in London, the son of Richard Hovill Seeley, goldsmith, and his second wife Mary Govier. He attended classes at the Royal School of Mines, Kensington before becoming an assistant to Adam Sedgwick at the Woodwardian Museum,...

 divided dinosaurs into the two orders Saurischia
Saurischia
Saurischia meaning 'lizard' and ischion meaning 'hip joint') is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...

 and Ornithischia
Ornithischia
Ornithischia or Predentata is an extinct order of beaked, herbivorous dinosaurs. The name ornithischia is derived from the Greek ornitheos meaning 'of a bird' and ischion meaning 'hip joint'...

, based on their hip structure. These divisions have proved remarkably enduring, even through several seismic changes in the taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...

 of dinosaurs.

The largest change was prompted by entomologist Willi Hennig
Willi Hennig
Emil Hans Willi Hennig was a German biologist who is considered the founder of phylogenetic systematics, also known as cladistics. With his works on evolution and systematics he revolutionised the view of the natural order of beings...

's work in the 1950s, which evolved into modern cladistics
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

. For specimens known only from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s, the rigorous analysis of characters
Synapomorphy
In cladistics, a synapomorphy or synapomorphic character is a trait that is shared by two or more taxa and their most recent common ancestor, whose ancestor in turn does not possess the trait. A synapomorphy is thus an apomorphy visible in multiple taxa, where the trait in question originates in...

 to determine evolutionary relationships between different groups of animals (clades) proved incredibly useful. When computer-based analysis using cladistics came into its own in the 1990s, paleontologists
Paleontology
Paleontology "old, ancient", ὄν, ὀντ- "being, creature", and λόγος "speech, thought") is the study of prehistoric life. It includes the study of fossils to determine organisms' evolution and interactions with each other and their environments...

 became among the first zoologists
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...

 to almost wholeheartedly adopt the system. Progressive scrutiny and work upon dinosaurian interrelationships, with the aid of new discoveries that have shed light on previously uncertain relationships between taxa, have begun to yield a stabilizing classification since the mid-2000s. While cladistics is the predominant classificatory system among paleontology professionals, the Linnean system is still in use, especially in works intended for popular distribution.

Benton classification


As most dinosaur paleontologists have advocated a shift away from traditional, ranked Linnaean taxonomy
Linnaean taxonomy
Linnaean taxonomy can mean either of two related concepts:# the particular form of biological classification set up by Carl Linnaeus, as set forth in his Systema Naturæ and subsequent works...

 in favor of rankless phylogentic systems, few ranked taxonomies of dinosaurs have been published since the 1980s. The following schema is among the most recent, from the third edition of Vertebrate Palaeontology
Vertebrate Palaeontology (Benton)
Vertebrate Palaeontology is a basic textbook on vertebrate paleontology by Michael J. Benton, published by Blackwell's. It has so far appeared in three editions, published in 1990, 1997, and 2005...

, a respected undergraduate textbook. While it is structured so as to reflect evolutionary relationships (similar to a cladogram
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

), it also retains the traditional ranks used in Linnaean taxonomy. The classification has been updated from the second edition in 2000 to reflect new research, but remains fundamentally conservative.

Benton classifies all dinosaurs within the Series Amniota, Class Sauropsida
Sauropsida
Sauropsida is a group of amniotes that includes all existing reptiles and birds and their fossil ancestors, including the dinosaurs, the immediate ancestors of birds...

, Subclass Diapsida, Infraclass Archosauromorpha
Archosauromorpha
Archosauromorpha is an infraclass of diapsid reptiles that first appeared during the late Permian and became more common during the Triassic. Included in this infraclass are the groups Rhynchosauria, Trilophosauridae, Prolacertiformes, Archosauriformes, and, tentatively, Choristodera...

, Division Archosaur
Archosaur
Archosaurs are a group of diapsid amniotes whose living representatives consist of modern birds and crocodilians. This group also includes all extinct non-avian dinosaurs, many extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most...

ia, Subdivision Avemetatarsalia
Avemetatarsalia
Avemetatarsalia is a clade name established by British palaeontologist Michael Benton in 1999 for all crown group archosaurs that are closer to birds than to crocodiles. It includes a similarly defined subgroup, Ornithodira...

, Infradivision Ornithodira, and Superorder Dinosauria. Dinosauria is then divided into the two traditional orders, Saurischia
Saurischia
Saurischia meaning 'lizard' and ischion meaning 'hip joint') is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...

 and Ornithischia
Ornithischia
Ornithischia or Predentata is an extinct order of beaked, herbivorous dinosaurs. The name ornithischia is derived from the Greek ornitheos meaning 'of a bird' and ischion meaning 'hip joint'...

. The cross (†) is used to indicate taxa with no living members.

Order Saurischia

  • Suborder Theropoda
    Theropoda
    Theropoda is both a suborder of bipedal saurischian dinosaurs, and a clade consisting of that suborder and its descendants . Dinosaurs belonging to the suborder theropoda were primarily carnivorous, although a number of theropod groups evolved herbivory, omnivory, and insectivory...

    • †Infraorder Herrerasauria
    • †Infraorder Coelophysoidea
      Coelophysoidea
      Coelophysoids were common dinosaurs of the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the coelurosaurs, with which they were formerly...

    • †Infraorder Ceratosauria
      Ceratosauria
      Ceratosaurs are members of a group of theropod dinosaurs defined as all theropods sharing a more recent common ancestry with Ceratosaurus than with birds. There is presently no universally agreed upon listing of species or diagnostic characters of Ceratosauria, though they were less derived...

      • †Family Ceratosauridae
        Ceratosauridae
        Ceratosauridae is a family of theropod dinosaurs belonging to the infraorder Ceratosauria. Its type genus, Ceratosaurus, was first found in Jurassic rocks from North America. Ceratosauridae is made up of Ceratosaurus, found in North America, Tanzania, and Portugal, and Genyodectes, from the Late...

      • †Family Abelisauridae
        Abelisauridae
        Abelisauridae is a family of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous Period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are found on the modern continents of Africa and South America, as well as on the Indian...

    • Infraorder Tetanurae
      Tetanurae
      Tetanurae, or "stiff tails", is a clade that includes most theropod dinosaurs, as well as birds. Tetanurans first appear during the early or middle Jurassic Period.-Definition:...

      • †Division Carnosauria
        Carnosauria
        Carnosauria is a group of large predatory dinosaurs that lived during the Jurassic and Cretaceous periods. While it originally contained a wide assortment of giant theropods that were not closely related, the group has since been defined to encompass only the allosaurs and their closest kin...

        • †Sudivision Spinosauroidea
          • †Family Megalosauridae
          • †Family Spinosauridae
            Spinosauridae
            Spinosauridae is a family of specialised theropod dinosaurs. Members of this family were large, bipedal predators with elongated, crocodile-like skulls, sporting conical teeth with no or only very tiny serrations. The front dentary teeth fanned out, giving the animal a characteristic look...

        • †Subdivision Allosauroidea
          Allosauroidea
          Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Sinraptoridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae...

          • †Family Allosauridae
          • †Family Carcharodontosauridae
            Carcharodontosauridae
            Carcharodontosaurids were a group of carnivorous theropod dinosaurs. In 1931 Ernst Stromer named Carcharodontosauridae as a family, in modern paleontology this name indicates a clade within Carnosauria...

      • Division Coelurosauria
        Coelurosauria
        Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. In the past, it was used to refer to all small theropods, although this classification has been abolished...

        • †Family Coeluridae
          Coeluridae
          Coeluridae is a historically polyphyletic family of generally small, carnivorous dinosaurs from the late Jurassic Period...

        • Subdivision Maniraptoriformes
          Maniraptoriformes
          Maniraptoriformes is a clade of dinosaurs that contains ornithomimosaurs and maniraptors. This group was named by Thomas Holtz, who defined it as "the most recent common ancestor of Ornithomimus and birds, and all descendants of that common ancestor."...

          • †Family Tyrannosauridae
            Tyrannosauridae
            Tyrannosauridae is a family of coelurosaurian theropod dinosaurs which comprises two subfamilies containing up to six genera, including the eponymous Tyrannosaurus. The exact number of genera is controversial, with some experts recognizing as few as three...

          • †Family Ornithomimidae
          • Infradivision Maniraptora
            Maniraptora
            Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosauria and Therizinosauria. Ornitholestes and the Alvarezsauroidea...

            • †Family Alvarezsauridae
              Alvarezsauridae
              Alvarezsauridae is an enigmatic family of small, long-legged running dinosaurs. Although originally thought to represent the earliest known flightless birds, a consensus of recent work suggests that they are primitive members of the Maniraptora. Other work found them to be the sister group to the...

            • †Family Therizinosauridae
              Therizinosauridae
              Therizinosauridae is a family of advanced herbivorous or omnivorous theropod dinosaurs. Therizinosaurid fossil remains have been recovered from mid-late Cretaceous Period deposits from Mongolia, China, and the United States.-Classification:...

            • †Cohort Deinonychosauria
              Deinonychosauria
              The Deinonychosauria were a clade of coelurosaurian theropod dinosaurs from the Late Jurassic and Cretaceous periods. These omnivores and carnivores are known for their switchblade-like second toe claws and for displaying numerous bird-like characteristics. The clade has been divided into two...

              • †Family Troodontidae
                Troodontidae
                Troodontidae is a family of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and scrappy and they have therefore been allied, at various times, with many dinosaurian lineages...

              • †Family Dromaeosauridae
                Dromaeosauridae
                Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

              • Class Aves
  • Suborder Sauropodomorpha
    Sauropodomorpha
    Sauropodomorpha is an extinct clade of long-necked, herbivorous, saurischian dinosaurs which includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The...

    • Thecodontosaurus
      Thecodontosaurus
      Thecodontosaurus is a genus of herbivorous basal sauropodomorph dinosaur which lived during the late Triassic period ....

    • †Family Plateosauridae
      Plateosauridae
      Plateosauridae is a family of plateosaurian sauropodomorphs. Plateosaurids were early sauropodomorph dinosaurs which existed in Asia, Europe and South America during the Late Triassic period. Although several dinosaurs have been classified as plateosaurids over the years, a 2007 study by Adam M....

    • Riojasaurus
      Riojasaurus
      Riojasaurus was a herbivorous prosauropod dinosaur named after La Rioja Province in Argentina where it was found by José Bonaparte. It lived during the Late Triassic and grew to about long. Riojasaurus is the only known riojasaurid to live in South America.-Description:Riojasaurus had a heavy...

    • †Family Massospondylidae
      Massospondylidae
      Massospondylidae is a family of massopod sauropodomorphs. Massospondylids are early sauropodomorph dinosaurs which existed in Asia, Africa and South America during the Late Triassic to the Early Jurassic periods...

    • †Infraorder Sauropoda
      Sauropoda
      Sauropoda , or the sauropods , are an infraorder of saurischian dinosaurs. They had long necks, long tails, small heads , and thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land...

      • †Family Vulcanodontidae
        Vulcanodontidae
        The Early Jurassic sauropod dinosaurs Zizhongosaurus, Barapasaurus, Tazoudasaurus, and Vulcanodon may form a natural group of basal sauropods called the Vulcanodontidae. Basal vulcanodonts include some of the earliest known examples of sauropods. The family-level name Vulcanodontidae was erected by...

      • †Family Omeisauridae
        Omeisauridae
        Omeisauridae is a family of sauropods. Wilson, when naming the family in 2002, included Omeisaurus and Mamenchisaurus, but if Mamenchisaurus is included, Mamenchisauridae has priority, as it was named in 1972...

      • †Division Neosauropoda
        Neosauropoda
        Neosauropoda is a division-level clade of sauropods within Dinosauria, and consists of the group leading to Diplodocoidea and Macronaria. Haplocanthosaurus was a typical basal neosauropod from around 150 million years ago, in the Late Jurassic...

        • †Family Cetiosauridae
        • †Family Diplodocidae
        • †Subdivision Macronaria
          Macronaria
          Macronaria is a clade of sauropod dinosaurs from the Middle Jurassic to Late Cretaceous Periods of what are now North America, South America, Europe, Asia and Africa. The name means 'large nostrils' , in reference to the large nasal openings high on the head that probably supported fleshy...

          • †Family Camarasauridae
          • †Infradivision Titanosauriformes
            • †Family Brachiosauridae
              Brachiosauridae
              Brachiosauridae are a family of dinosaurs, whose members are known as brachiosaurids. They were herbivorous quadrupeds with longer forelegs than hind legs - the name derives from the Greek for arm lizard - and long necks...

            • †Cohort Somphospondyli
              • †Family Euhelopodidae
                Euhelopodidae
                Euhelopodidae is a family of sauropod dinosaurs which includes the genus Euhelopus. The family name was first proposed by American paleontologist Alfred Sherwood Romer in 1956. The four genera Chiayusaurus, Omeisaurus, Tienshanosaurus, and Euhelopus were the original proposed euhelopodines...

              • †Family Titanosauridae

†Order Ornithischia

  • †Family Pisanosauridae
  • †Family Fabrosauridae
    Fabrosauridae
    The Fabrosauridae was originally proposed by Galton , as a group of basal ornithischian dinosaurs from the Early to Middle Jurassic. However, recent studies indicate the Fabrosaurs are not a natural grouping of dinosaurs, and instead consist of unrelated genera.The proposed "Fabrosaurs" descended...

  • †Suborder Thyreophora
    Thyreophora
    The Thyreophora were a subgroup of the ornithischian dinosaurs...

    • †Family Scelidosauridae
    • †Infraorder Stegosauria
      Stegosauria
      Known colloquially as stegosaurs, the Stegosauria are a group of herbivorous dinosaurs of the Jurassic and Early Cretaceous Periods, being found mostly in the Northern Hemisphere, predominantly in what is now North America and China....

    • †Infraorder Ankylosauria
      Ankylosauria
      Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are first known to have appeared in the early Jurassic Period of...

      • †Family Nodosauridae
        Nodosauridae
        Nodosauridae is a family of ankylosaurian dinosaurs, from the Late Jurassic to the Late Cretaceous Period of what are now North America, Asia, Antarctica and Europe.-Characteristics:...

      • †Family Ankylosauridae
        Ankylosauridae
        An ankylosaurid is a member of the Ankylosauridae family of armored dinosaurs that evolved 125 million years ago and became extinct 65 million years ago during the Cretaceous-Tertiary extinction event...

  • †Suborder Cerapoda
    Cerapoda
    Neornithischia is a clade of the dinosaur order Ornithischia. They are the sister group of the Thyreophora within the clade Genasauria. Neornithischians are united by having a thicker layer of asymmetrical enamel on the inside of their lower teeth...

    • †Infraorder Pachycephalosauria
      Pachycephalosauria
      Pachycephalosauria is a clade of ornithischian dinosaurs. Well-known genera include Pachycephalosaurus, Stegoceras, Stygimoloch, and Dracorex. Most lived during the Late Cretaceous Period, in what is now North America and Asia. They were all bipedal, herbivorous/omnivorous animals with thick skulls...

    • †Infraorder Ceratopsia
      Ceratopsia
      Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs which thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7...

      • †Family Psittacosauridae
        Psittacosauridae
        The Psittacosauridae were a group of ceratopsian dinosaurs, which lived between 140.2 and 99.6 million years ago. The family Psittacosauridae was first named by American paleontologist Henry Fairfield Osborn in 1923...

      • †Family Protoceratopsidae
      • †Family Ceratopsidae
        Ceratopsidae
        Ceratopsidae is a speciose group of marginocephalian dinosaurs including Triceratops and Styracosaurus...

    • †Infraorder Ornithopoda
      • †Family Heterodontosauridae
        Heterodontosauridae
        Heterodontosauridae is a family of early ornithischian dinosaurs that were likely among the most basal members of the group...

      • †Family Hypsilophodontidae
      • †Family Iguanodontidae *
      • †Family Hadrosauridae

Weishampel/Dodson/Osmólska classification


The following is based on the second edition of The Dinosauria, a compilation of articles by experts in the field that provided the most comprehensive coverage of Dinosauria available when it was first published in 1990. The second edition updates and revises that work.

The cladogram and phylogenetic definitions below reflect the current understanding of evolutionary relationships. The taxa and symbols in parentheses after a given taxa define these relationships. The plus symbol ("+") between taxa indicates the given taxa is a node-based clade, defined as comprising all descendants of the last common ancestor of the "added" taxa. The greater-than symbol (">") indicates the given taxon is a stem-based taxon, comprising all organisms sharing a common ancestor that is not also an ancestor of the "lesser" taxon.

Saurischia


(Tyrannosaurus
Tyrannosaurus
Tyrannosaurus meaning "tyrant," and sauros meaning "lizard") is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex , commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other...

/Allosaurus
Allosaurus
Allosaurus is a genus of large theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period . The name Allosaurus means "different lizard". It is derived from the Greek /allos and /sauros...

> Triceratops
Triceratops
Triceratops is a genus of herbivorous ceratopsid dinosaur which lived during the late Maastrichtian stage of the Late Cretaceous Period, around 68 to 65 million years ago in what is now North America. It was one of the last dinosaur genera to appear before the great Cretaceous–Paleogene...

/Stegosaurus
Stegosaurus
Stegosaurus is a genus of armored stegosaurid dinosaur. They lived during the Late Jurassic period , some 155 to 150 million years ago in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well...

)
  • Herrerasauria (Herrerasaurus
    Herrerasaurus
    Herrerasaurus was one of the earliest dinosaurs. All known specimens of this carnivore have been discovered in rocks of late Ladinian age in northwestern Argentina...

    > Liliensternus, Plateosaurus
    Plateosaurus
    Plateosaurus is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 216 to 199 million years ago, in what is now Central and Northern Europe. Plateosaurus is a basal sauropodomorph dinosaur, a so-called "prosauropod"...

    )
    • Herrerasauridae
      Herrerasauridae
      Herrerasaurids are among the oldest known dinosaurs, appearing in the fossil record 231.4 million years ago . They became extinct by the end of the Triassic period. Herrerasaurids were small-sized carnivorous theropods or basal saurischians...

       (Herrerasaurus + Staurikosaurus
      Staurikosaurus
      Staurikosaurus is a genus of herrerasaurid dinosaur from the Late Triassic of Brazil.-Discovery:The first known specimen of Staurikosaurus was recovered from the Paleontological Site Jazigo Cinco of the Santa Maria Formation in the geopark of paleorrota , Rio Grande do Sul, southern Brazil...

      )
  • ? Eoraptor
    Eoraptor
    Eoraptor was one of the world's earliest dinosaurs. It was a two-legged saurischian, close to the ancestry of theropods and sauropodomorphs. It lived ca. 231.4 million years ago, in what is now the northwestern region of Argentina...

     lunensis
  • Sauropodomorpha
    Sauropodomorpha
    Sauropodomorpha is an extinct clade of long-necked, herbivorous, saurischian dinosaurs which includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The...

    (Saltasaurus
    Saltasaurus
    Saltasaurus is a genus of titanosaurid sauropod dinosaur of the Late Cretaceous Period. Relatively small among sauropods, though still massive by the standards of modern creatures, Saltasaurus was characterized by a diplodocid-like head...

    > Theropoda
    Theropoda
    Theropoda is both a suborder of bipedal saurischian dinosaurs, and a clade consisting of that suborder and its descendants . Dinosaurs belonging to the suborder theropoda were primarily carnivorous, although a number of theropod groups evolved herbivory, omnivory, and insectivory...

    )
    • ? Saturnalia
      Saturnalia (dinosaur)
      Saturnalia is an extinct genus of basal sauropodomorph dinosaur known from the Triassic of Rio Grande do Sul, southern Brazil.-Discovery:Saturnalia was originally named on the basis of three partial skeletons...

       tupiniquim
    • ? Thecodontosauridae
    • Prosauropoda (Plateosaurus
      Plateosaurus
      Plateosaurus is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 216 to 199 million years ago, in what is now Central and Northern Europe. Plateosaurus is a basal sauropodomorph dinosaur, a so-called "prosauropod"...

      > Sauropoda
      Sauropoda
      Sauropoda , or the sauropods , are an infraorder of saurischian dinosaurs. They had long necks, long tails, small heads , and thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land...

      )
      • ? Thecodontosauridae
      • ? Anchisauria
        Anchisauria
        The Anchisauria were a clade of sauropodomorph dinosaurs which lived during the Late Triassic and Early Jurassic. The name Anchisauria was first used by Galton and Upchurch in the second edition of The Dinosauria...

         (Anchisaurus
        Anchisaurus
        Anchisaurus is a genus of basal sauropodomorph, and was an early herbivorous dinosaur. Until recently it was classed as a member of Prosauropoda. The name comes from the Greek αγχι/agkhi...

        + Melanorosaurus
        Melanorosaurus
        Melanorosaurus , is a genus of basal sauropodomorph dinosaur that lived during the Late Triassic period. A herbivore from South Africa, it had a large body and sturdy limbs, suggesting it moved about on all fours...

        )
        • ? Anchisauridae
          Anchisauridae
          The Anchisauridae were a group of early sauropodomorph dinosaurs first proposed by Othniel Charles Marsh in 1885. The clade consists of Anchisaurus and its nearest relatives. However, it is not clear which other genera are included in the family; many of the dinosaurs once included have since been...

           (Anchisaurus > Melanorosaurus)
        • ? Melanorosauridae
          Melanorosauridae
          The Melanorosauridae were a family of sauropodomorph dinosaurs which lived during the Late Triassic and Early Jurassic. The name Melanorosauridae was first coined by Friedrich von Huene in 1929. Huene assigned several families of dinosaurs to the infraorder Prosauropoda: the Anchisauridae, the...

           (
          Melanorosaurus > Anchisaurus)
      • Plateosauria
        Plateosauria
        Plateosauria is a clade of sauropodomorph dinosaurs which lived during the Late Triassic to the Late Cretaceous. The name Plateosauria was first coined by Gustav Tornier in 1913. The name afterwards fell out of use until the 1980s, when a new generation of paleontologists began using the name...

         (
        Jingshanosaurus
        Jingshanosaurus
        Jingshanosaurus is a genus of prosauropod dinosaurs from the Early Jurassic. Its fossils, a nearly complete skeleton including the skull, were found near the town of Jingshan , Lufeng County, Yunnan Province, China, from which the name derives. First described in 1995, the type species is J....

        + Plateosaurus)
        • Massospondylidae
          Massospondylidae
          Massospondylidae is a family of massopod sauropodomorphs. Massospondylids are early sauropodomorph dinosaurs which existed in Asia, Africa and South America during the Late Triassic to the Early Jurassic periods...

        • Yunnanosauridae
          Yunnanosaurus
          Yunnanosaurus is a genus of prosauropod dinosaur from the Early to Middle Jurassic Period, a position in time that makes it one of the last prosauropods. It is closely related to Lufengosaurus...

        • Plateosauridae
          Plateosauridae
          Plateosauridae is a family of plateosaurian sauropodomorphs. Plateosaurids were early sauropodomorph dinosaurs which existed in Asia, Europe and South America during the Late Triassic period. Although several dinosaurs have been classified as plateosaurids over the years, a 2007 study by Adam M....

           (
          Plateosaurus > Yunnanosaurus, Massospondylus
          Massospondylus
          Massospondylus and ) is a genus of prosauropod dinosaur from the early Jurassic Period . It was described by Sir Richard Owen in 1854 from remains found in South Africa, and is thus one of the first dinosaurs to have been named...

          )
    • Sauropoda
      Sauropoda
      Sauropoda , or the sauropods , are an infraorder of saurischian dinosaurs. They had long necks, long tails, small heads , and thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land...

       (
      Saltasaurus > Plateosaurus)
      • ? Anchisauridae
        Anchisauridae
        The Anchisauridae were a group of early sauropodomorph dinosaurs first proposed by Othniel Charles Marsh in 1885. The clade consists of Anchisaurus and its nearest relatives. However, it is not clear which other genera are included in the family; many of the dinosaurs once included have since been...

      • ? Melanorosauridae
        Melanorosauridae
        The Melanorosauridae were a family of sauropodomorph dinosaurs which lived during the Late Triassic and Early Jurassic. The name Melanorosauridae was first coined by Friedrich von Huene in 1929. Huene assigned several families of dinosaurs to the infraorder Prosauropoda: the Anchisauridae, the...

      • Blikanasauridae
        Blikanasauridae
        The Blikanasauridae were a group of early sauropodomorph dinosaurs. The clade was first proposed by Galton and van Heerden in 1985. The family consists of Blikanasaurus and its nearest relatives. However, it is not clear which other genera are included in the family. The family is not used in many...

      • Vulcanodontidae
        Vulcanodontidae
        The Early Jurassic sauropod dinosaurs Zizhongosaurus, Barapasaurus, Tazoudasaurus, and Vulcanodon may form a natural group of basal sauropods called the Vulcanodontidae. Basal vulcanodonts include some of the earliest known examples of sauropods. The family-level name Vulcanodontidae was erected by...

      • Eusauropoda (Shunosaurus
        Shunosaurus
        Shunosaurus, meaning "Shu Lizard", is a genus of sauropod dinosaur from Middle Jurassic beds in Sichuan Province in China, 170 million years ago...

        + Saltasaurus)
        • ? Euhelopodidae
          Euhelopodidae
          Euhelopodidae is a family of sauropod dinosaurs which includes the genus Euhelopus. The family name was first proposed by American paleontologist Alfred Sherwood Romer in 1956. The four genera Chiayusaurus, Omeisaurus, Tienshanosaurus, and Euhelopus were the original proposed euhelopodines...

        • Mamenchisauridae
          Mamenchisauridae
          Mamenchisauridae is an extinct family of sauropod dinosaurs. The family was first named by Chinese paleontologists C.C. Young and H.C. Chao in 1972, in a paper describing Mamenchisaurus. Other mamenchisaurids may include Bellusaurus, Chuanjiesaurus, Eomamenchisaurus, Hudiesaurus, Klamelisaurus,...

        • Cetiosauridae (Cetiosaurus
          Cetiosaurus
          Cetiosaurus meaning 'whale lizard', from the Greek cetus/κητος meaning 'sea monster' and saurus/σαυρος meaning 'lizard', was a sauropod dinosaur from the Mid to Late Jurassic Period in what are now Europe and Africa. It is estimated to have been about long and to have weighed roughly...

          > Saltasaurus)
        • Neosauropoda
          Neosauropoda
          Neosauropoda is a division-level clade of sauropods within Dinosauria, and consists of the group leading to Diplodocoidea and Macronaria. Haplocanthosaurus was a typical basal neosauropod from around 150 million years ago, in the Late Jurassic...

           (
          Diplodocus
          Diplodocus
          Diplodocus , or )is a genus of diplodocid sauropod dinosaur whose fossils were first discovered in 1877 by S. W. Williston. The generic name, coined by Othniel Charles Marsh in 1878, is a Neo-Latin term derived from Greek "double" and "beam", in reference to its double-beamed chevron bones...

          + Saltasaurus)
          • Diplodocoidea
            Diplodocoidea
            Diplodocoidea was a superfamily of sauropod dinosaurs, which included some of the longest animals of all time, including slender giants like Supersaurus, Diplodocus, Apatosaurus, and Amphicoelias...

             (
            Diplodocus > Saltasaurus)
            • Rebbachisauridae
              Rebbachisauridae
              Rebbachisauridae is a family of sauropod dinosaurs known from fragmentary fossil remains from the Cretaceous of South America, Africa, and Europe.-Taxonomy:...

               (
              Rebbachisaurus
              Rebbachisaurus
              Rebbachisaurus is a genus of sauropod dinosaur of the superfamily Diplodocoidea, up to 20 meters long, that lived during the Early-Late Cretaceous period in Africa about 99 million years ago. This massive four-legged plant-eating animal had a small head, a long, graceful neck and a whiplike...

              > Diplodocus)
            • Flagellicaudata
              • Dicraeosauridae
                Dicraeosauridae
                Dicraeosauridae is a family of sauropod dinosaurs known from the Late Jurassic and Early Cretaceous of Africa and South America. Currently only three genera are recognised; the Jurassic South American genus Brachytrachelopan, the Jurassic African Dicraeosaurus and the South American Early...

                 (
                Dicraeosaurus
                Dicraeosaurus
                Dicraeosaurus is a genus of small diplodocoid sauropod dinosaur. It was named for the spines on the back of the neck. The first fossil was described by paleontologist Werner Janensch in 1914.Unlike most diplodocoids, Dicraeosaurus had a large head with a relatively short and wide neck...

                > Diplodocus)
              • Diplodocidae (Diplodocus > Dicraeosaurus)
          • Macronaria
            Macronaria
            Macronaria is a clade of sauropod dinosaurs from the Middle Jurassic to Late Cretaceous Periods of what are now North America, South America, Europe, Asia and Africa. The name means 'large nostrils' , in reference to the large nasal openings high on the head that probably supported fleshy...

             (
            Saltasaurus > Diplodocus)
            • ? Jobaria
              Jobaria
              Jobaria was a sauropod dinosaur discovered in the Sahara Desert in 1997. It was named after "Jobar", a creature of local legends, and is thought to have been about 18 metres long. It was found in the Tiourarén Formation, originally thought to represent the Hauterivian to Barremian stages of the...

               tiguidensis
            • Camarasauromorpha (Camarasaurus
              Camarasaurus
              Camarasaurus meaning 'chambered lizard', referring to the hollow chambers in its vertebrae was a genus of quadrupedal, herbivorous dinosaurs. It was the most common of the giant sauropods to be found in North America...

              + Saltasaurus)
              • Camarasauridae
              • Titanosauriformes (Brachiosaurus
                Brachiosaurus
                Brachiosaurus is a genus of sauropod dinosaur from the Jurassic Morrison Formation of North America. It was first described by Elmer S. Riggs in 1903 from fossils found in the Grand River Canyon of western Colorado, in the United States. Riggs named the dinosaur Brachiosaurus altithorax,...

                + Saltasaurus)
                • Brachiosauridae
                  Brachiosauridae
                  Brachiosauridae are a family of dinosaurs, whose members are known as brachiosaurids. They were herbivorous quadrupeds with longer forelegs than hind legs - the name derives from the Greek for arm lizard - and long necks...

                   (
                  Brachiosaurus > Saltasaurus)
                • Titanosauria (Saltasaurus > Brachiosaurus)
                  • Andesauridae
                  • Lithostrotia (Malawisaurus
                    Malawisaurus
                    Malawisaurus was a genus of sauropod dinosaur . It lived in what is now Africa, specifically Malawi, during the Aptian age of the Early Cretaceous Period. It is one of the few titanosaurs for which skull material has been found.It was named by Louis L. Jacobs and colleagues, and was originally...

                    + Saltasaurus)
                    • Isisaurus
                      Isisaurus
                      Isisaurus is a genus of dinosaur from the Late Cretaceous Period. Isisaurus was a sauropod , which lived in what is now India....

                       colberti
                    • Paralititan
                      Paralititan
                      Paralititan was a giant titanosaurian sauropod dinosaur genus discovered in coastal deposits in the Upper Cretaceous Bahariya Formation of Egypt. The fossil represents the first tetrapod reported from the Bahariya Formation since 1935. Its 1.69 meter long humerus is longer than that of any...

                       stromeri
                    • Nemegtosauridae
                      Nemegtosauridae
                      Nemegtosauridae is a family of probably titanosaurian sauropod dinosaurs based originally on two late Cretaceous Mongolian species known only from their diplodocid-like skulls: Nemegtosaurus and Quaesitosaurus. Authorities disagree as to the relationship of these two genera with other sauropods,...

                    • Saltasauridae
                      Saltasauridae
                      Saltasauridae is a family of titanosaurian dinosaurs known from the late Cretaceous period of South America, Spain, Madagascar and Mongolia....

                       (
                      Opisthocoelicaudia
                      Opisthocoelicaudia
                      Opisthocoelicaudia was 12-metre-long sauropod dinosaur of the Late Cretaceous Period discovered in Mongolia in 1965 by Polish and Mongolian scientists in what is now the Gobi Desert...

                      + Saltasaurus)
  • Theropoda
    Theropoda
    Theropoda is both a suborder of bipedal saurischian dinosaurs, and a clade consisting of that suborder and its descendants . Dinosaurs belonging to the suborder theropoda were primarily carnivorous, although a number of theropod groups evolved herbivory, omnivory, and insectivory...

    (
    Passer domesticus
    Passer
    Passer is a genus of Old World sparrows. These sparrows are plump little brown or greyish birds often with black, yellow or white markings. Typically 10–20 cm long, they have short tails and stubby conical beaks...

    > Cetiosaurus oxoniensis)
    • ? Eoraptor
      Eoraptor
      Eoraptor was one of the world's earliest dinosaurs. It was a two-legged saurischian, close to the ancestry of theropods and sauropodomorphs. It lived ca. 231.4 million years ago, in what is now the northwestern region of Argentina...

       lunensis
    • ? Herrerasauridae
    • Ceratosauria
      Ceratosauria
      Ceratosaurs are members of a group of theropod dinosaurs defined as all theropods sharing a more recent common ancestry with Ceratosaurus than with birds. There is presently no universally agreed upon listing of species or diagnostic characters of Ceratosauria, though they were less derived...

       (
      Ceratosaurus
      Ceratosaurus
      Ceratosaurus meaning "horned lizard", in reference to the horn on its nose , was a large predatory theropod dinosaur from the Late Jurassic Period , found in the Morrison Formation of North America, in Tanzania and Portugal...

       nasicornis > Aves)
      • ? Coelophysoidea
        Coelophysoidea
        Coelophysoids were common dinosaurs of the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the coelurosaurs, with which they were formerly...

         (
        Coelophysis
        Coelophysis
        Coelophysis , meaning "hollow form" in reference to its hollow bones , is one of the earliest known genera of dinosaur...

        > Ceratosaurus)
        • ? Dilophosaurus
          Dilophosaurus
          Dilophosaurus was a theropod dinosaur from the Sinemurian stage of the Early Jurassic Period, about 193 million years ago. The first specimens were described in 1954, but it was not until over a decade later that the genus received its current name...

           wetherilli
        • Coelophysidae
          Coelophysidae
          The Coelophysidae are a family of primitive carnivorous theropod dinosaurs. Most species were relatively small in size. The family flourished in the Late Triassic and Early Jurassic periods....

           (
          Coelophysis
          Coelophysis
          Coelophysis , meaning "hollow form" in reference to its hollow bones , is one of the earliest known genera of dinosaur...

          + Megapnosaurus
          Megapnosaurus
          Megapnosaurus was a dinosaur of the theropod family Coelophysidae, formerly called Syntarsus , living during the Early Jurassic. It was renamed by American entomologist Dr. Michael Ivie , Polish Australian Dr...

          )
      • ? Neoceratosauria (Ceratosaurus > Coelophysis)
        • Ceratosauridae
          Ceratosauridae
          Ceratosauridae is a family of theropod dinosaurs belonging to the infraorder Ceratosauria. Its type genus, Ceratosaurus, was first found in Jurassic rocks from North America. Ceratosauridae is made up of Ceratosaurus, found in North America, Tanzania, and Portugal, and Genyodectes, from the Late...

        • Abelisauroidea (Carnotaurus
          Carnotaurus
          Carnotaurus was a large predatory dinosaur. Only one species, Carnotaurus sastrei has been described so far.Carnotaurus lived in Patagonia, Argentina during the Campanian or Maastrichtian stage of the Late Cretaceous...

           sastrei > C. nasicornis)
          • Abelisauria (Noasaurus
            Noasaurus
            Noasaurus is the name given to a carnivorous dinosaur genus of the late Campanian-Maastrichtian...

            + Carnotaurus
            Carnotaurus
            Carnotaurus was a large predatory dinosaur. Only one species, Carnotaurus sastrei has been described so far.Carnotaurus lived in Patagonia, Argentina during the Campanian or Maastrichtian stage of the Late Cretaceous...

            )
            • Noasauridae
              Noasauridae
              Noasaurids were a group of theropod dinosaurs from the Cretaceous Period . They were generally small in size...

            • Abelisauridae
              Abelisauridae
              Abelisauridae is a family of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous Period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are found on the modern continents of Africa and South America, as well as on the Indian...

               (
              Abelisaurus
              Abelisaurus
              Abelisaurus is a genus of abelisaurid theropod dinosaur from the Late Cretaceous Period of what is now South America. It was a bipedal carnivore that probably reached 7 to 9 meters in length, although it is known from only one partial skull.The generic name recognizes Roberto Abel as the...

               comahuensis + C. sastrei)
              • Carnotaurinae
                Carnotaurinae
                Carnotaurinae is a subfamily of the theropod dinosaur family Abelisauridae. It includes the dinosaurs Aucasaurus , Carnotaurus , Majungasaurus , and Rajasaurus...

                 (
                Carnotaurus > Abelisaurus)
              • Abelisaurinae (Abelisaurus > Carnotaurus)
    • Tetanurae
      Tetanurae
      Tetanurae, or "stiff tails", is a clade that includes most theropod dinosaurs, as well as birds. Tetanurans first appear during the early or middle Jurassic Period.-Definition:...

       (
      P. domesticus > C. nasicornis)
      • ? Spinosauroidea (Spinosaurus
        Spinosaurus
        Spinosaurus is a genus of theropod dinosaur which lived in what is now North Africa, from the lower Albian to lower Cenomanian stages of the Cretaceous period, about 112 to 97 million years ago. This genus was first known from Egyptian remains discovered in 1912 and described by German...

         aegyptiacus > P. domesticus)
        • Megalosauridae (Megalosaurus
          Megalosaurus
          Megalosaurus is a genus of large meat-eating theropod dinosaurs of the Middle Jurassic period of Europe...

           bucklandii > P. domesticus, S. aegyptiacus, Allosaurus fragilis)
          • Megalosaurinae (M. bucklandii > Eustreptospondylus
            Eustreptospondylus
            Eustreptospondylus is a genus of megalosaurid dinosaur, from the Callovian stage of the Middle Jurassic period in southern England, at a time when Europe was a series of scattered islands Eustreptospondylus ("well-curved vertebra", in reference to the arrangement of the spine in the original...

             oxoniensis)
          • Eustreptospondylinae (E. oxoniensis > M. bucklandii)
        • Spinosauridae
          Spinosauridae
          Spinosauridae is a family of specialised theropod dinosaurs. Members of this family were large, bipedal predators with elongated, crocodile-like skulls, sporting conical teeth with no or only very tiny serrations. The front dentary teeth fanned out, giving the animal a characteristic look...

           (
          S. aegyptiacus > P. domesticus, M. bucklandii, A. fragilis)
          • Baryonychinae (Baryonyx
            Baryonyx
            Baryonyx is a genus of carnivorous saurischian dinosaur first discovered in clay pits just south of Dorking, England, and later reported from fossils found in northern Spain and Portugal. It is known to contain only one species, Baryonyx walkeri...

             walkeri > S. aegyptiacus)
          • Spinosaurinae (S. aegyptiacus > B. walkeri)
      • Avetheropoda (A. fragilis + P. domesticus)
        • Carnosauria
          Carnosauria
          Carnosauria is a group of large predatory dinosaurs that lived during the Jurassic and Cretaceous periods. While it originally contained a wide assortment of giant theropods that were not closely related, the group has since been defined to encompass only the allosaurs and their closest kin...

           (
          A. fragilis > Aves)
          • ? Spinosauroidea
          • Monolophosaurus
            Monolophosaurus
            Monolophosaurus was a genus of theropod dinosaur from the Middle Jurassic of the Shishugou Formation in what is now Xinjiang, China. It was named for the single crest on top of its skull. The type and only known individual is estimated at...

             jiangi
          • Allosauroidea
            Allosauroidea
            Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Sinraptoridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae...

             (
            A. fragilis + Sinraptor
            Sinraptor
            Sinraptor is a genus of theropod dinosaur from the Late Jurassic. The name Sinraptor comes from the Latin prefix "Sino", meaning Chinese, and "Raptor" meaning thief. The specific name dongi honours Dong Zhiming...

             dongi)
            • Allosauridae (A. fragilis > S. dongi, Carcharodontosaurus
              Carcharodontosaurus
              Carcharodontosaurus was a gigantic carnivorous carcharodontosaurid dinosaur that lived around 100 to 93 million years ago, during the late Albian to early Cenomanian stages of the mid-Cretaceous Period...

               saharicus)
            • Sinraptoridae
              Sinraptoridae
              Sinraptorids were a family of carnivorous theropod dinosaurs. They tended to be large predators, some growing to sizes of . Sinraptorids are carnosaurs, and many were initially classified within Megalosauridae or Allosauridae prior to recent analysis...

               (
              S. dongi > A. fragilis, C. saharicus)
            • Carcharodontosauridae
              Carcharodontosauridae
              Carcharodontosaurids were a group of carnivorous theropod dinosaurs. In 1931 Ernst Stromer named Carcharodontosauridae as a family, in modern paleontology this name indicates a clade within Carnosauria...

               (
              C. saharicus > A. fragilis, S. dongi)
        • Coelurosauria
          Coelurosauria
          Coelurosauria is the clade containing all theropod dinosaurs more closely related to birds than to carnosaurs. In the past, it was used to refer to all small theropods, although this classification has been abolished...

           (
          P. domesticus > A. fragilis)
          • Compsognathidae
            Compsognathidae
            Compsognathidae is a family of small carnivorous dinosaurs, generally conservative in form, from the Jurassic and Cretaceous Periods. Compsognathids lie at or near the origin of feathers—skin impressions are known from four genera, Compsognathus, Sinosauropteryx, Sinocalliopteryx, and Juravenator...

             (
            Compsognathus
            Compsognathus
            Compsognathus was a small, bipedal, carnivorous theropod dinosaur. The animal was the size of a turkey and lived around 150 million years ago, the early Tithonian stage of the late Jurassic Period, in what is now Europe. Paleontologists have found two well-preserved fossils, one in Germany...

             longipes > P. domesticus)
          • Proceratosaurus
            Proceratosaurus
            Proceratosaurus is a genus of small-sized carnivorous theropod dinosaur from the Middle Jurassic of England. It was originally thought to be an ancestor of Ceratosaurus, due to the similar small crest on its snout...

             bradleyi
          • Ornitholestes
            Ornitholestes
            Ornitholestes was a small theropod dinosaur of the late Jurassic of Western Laurasia . To date, it is known only from a single partial skeleton, and badly crushed skull found at the Bone Cabin Quarry near Medicine Bow, Wyoming, in 1900...

             hermanni
          • Tyrannoraptora (Tyrannosaurus
            Tyrannosaurus
            Tyrannosaurus meaning "tyrant," and sauros meaning "lizard") is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex , commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other...

             rex + P. domesticus)
            • Coelurus
              Coelurus
              Coelurus is a genus of coelurosaur dinosaur from the Late Jurassic period . The name means "hollow tail", referring to its hollow tail vertebrae...

               fragilis
            • Tyrannosauroidea
              Tyrannosauroidea
              Tyrannosauroidea is a superfamily of coelurosaurian theropod dinosaurs that includes the family Tyrannosauridae as well as more basal relatives. Tyrannosauroids lived on the Laurasian supercontinent beginning in the Jurassic Period...

               (
              T. rex > Ornithomimus
              Ornithomimus
              Ornithomimus is a genus of ornithomimid dinosaur from the Late Cretaceous Period of what is now North America.In 1890 Ornithomimus velox was named by Othniel Charles Marsh on the basis of a foot and partial hand from the Maastrichtian Denver Formation. Another seventeen species have been named since...

               velox, Deinonychus
              Deinonychus
              Deinonychus was a genus of carnivorous dromaeosaurid dinosaur. There is one described species, Deinonychus antirrhopus. This 3.4 meter long dinosaur lived during the early Cretaceous Period, about 115–108 million years ago . Fossils have been recovered from the U.S...

               antirrhopus, A. fragilis)
              • Dryptosauridae
              • Tyrannosauridae
                Tyrannosauridae
                Tyrannosauridae is a family of coelurosaurian theropod dinosaurs which comprises two subfamilies containing up to six genera, including the eponymous Tyrannosaurus. The exact number of genera is controversial, with some experts recognizing as few as three...

                 (
                T. rex + Tarbosaurus
                Tarbosaurus
                Tarbosaurus is a genus of tyrannosaurid theropod dinosaur that flourished in Asia about 70 million years ago, at the end of the Late Cretaceous Period. Fossils have been recovered in Mongolia, with more fragmentary remains found further afield in parts of China. Although many species have been...

                 bataar + Daspletosaurus
                Daspletosaurus
                Daspletosaurus is a genus of tyrannosaurid theropod dinosaur that lived in western North America between 77 and 74 million years ago, during the Late Cretaceous Period. Fossils of the only named species were found in Alberta, although other possible species from Alberta and Montana await...

                 torosus + Albertosaurus
                Albertosaurus
                Albertosaurus is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, more than 70 million years ago. The type species, A. sarcophagus, was apparently restricted in range to the modern-day Canadian province of Alberta, after which...

                 sarcophagus + Gorgosaurus
                Gorgosaurus
                Gorgosaurus is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, between about 76.5 and 75 million years ago. Fossil remains have been found in the Canadian province of Alberta and possibly the U.S. state of Montana....

                 libratus)
                • Tyrannosaurinae (T. rex > A. sarcophagus)
                • Albertosaurinae (A. sarcophagus > T. rex)
            • Maniraptoriformes
              Maniraptoriformes
              Maniraptoriformes is a clade of dinosaurs that contains ornithomimosaurs and maniraptors. This group was named by Thomas Holtz, who defined it as "the most recent common ancestor of Ornithomimus and birds, and all descendants of that common ancestor."...

               (
              O. velox + P. domesticus)
              • Ornithomimosauria
                Ornithomimosauria
                The Ornithomimosauria, ornithomimosaurs or ostrich dinosaurs were theropod dinosaurs which bore a superficial resemblance to modern ostriches. They were fast, omnivorous or herbivorous dinosaurs from the Cretaceous Period of Laurasia...

                 (
                Ornithomimus
                Ornithomimus
                Ornithomimus is a genus of ornithomimid dinosaur from the Late Cretaceous Period of what is now North America.In 1890 Ornithomimus velox was named by Othniel Charles Marsh on the basis of a foot and partial hand from the Maastrichtian Denver Formation. Another seventeen species have been named since...

                 edmontonicus + Pelecanimimus polyodon)
                • Harpymimidae
                • Garudimimidae
                • Ornithomimidae
              • Maniraptora
                Maniraptora
                Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosauria and Therizinosauria. Ornitholestes and the Alvarezsauroidea...

                 (
                P. domesticus > O. velox)
                • Oviraptorosauria
                  Oviraptorosauria
                  Oviraptorosaurs are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot - like skulls, with or without bony crests atop the head...

                   (
                  Oviraptor
                  Oviraptor
                  Oviraptor is a genus of small Mongolian theropod dinosaur, first discovered by the paleontologist Roy Chapman Andrews, and first described by Henry Fairfield Osborn, in 1924...

                   philoceratops > P. domesticus)
                  • Caenagnathoidea
                    Caenagnathoidea
                    Caenagnathoidea is a group of advanced oviraptorosaurian dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot - like skulls, often with bony crests atop the head...

                     (
                    O. philoceratops + Caenagnathus collinsi)
                    • Caenagnathidae (C. collinsi > O. philoceratops)
                    • Oviraptoridae
                      Oviraptoridae
                      Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one and two metres long in most cases, though some...

                       (
                      O. philoceratops > C. collinsi)
                      • Oviraptorinae
                        Oviraptorinae
                        Oviraptorinae is a subfamily of bird-like maniraptoran theropod dinosaurs within the clade Oviraptoridae.-Classification and species: The classification of the oviraptorids has been controversial...

                         (
                        O. philoceratops + Citipati osmolskae)
                  • Therizinosauroidea (Therizinosaurus
                    Therizinosaurus
                    Therizinosaurus is a genus of very large theropod dinosaur. Therizinosaurus lived in the late Cretaceous Period , and was one of the last and largest representatives of its unique group, the Therizinosauria...

                    + Beipiaosaurus
                    Beipiaosaurus
                    Beipiaosaurus is a genus of therizinosauroid theropod dinosaur from the Early Cretaceous of China.The exact classification of therizinosaurs had in the past been hotly debated, since their prosauropod-like teeth and body structure indicate that they were generally herbivorous, unlike typical...

                    )
                    • Alxasauridae
                    • Therizinosauridae
                      Therizinosauridae
                      Therizinosauridae is a family of advanced herbivorous or omnivorous theropod dinosaurs. Therizinosaurid fossil remains have been recovered from mid-late Cretaceous Period deposits from Mongolia, China, and the United States.-Classification:...

                • Paraves
                  Paraves
                  Paraves is a branch-based clade containing birds and other closely related dinosaurs. The paravians include the Avialae, including Archaeopteryx and modern birds, and the Deinonychosauria, which includes the dromaeosaurids and troodontids....

                   (
                  P. domesticus > O. philoceratops)
                  • Eumaniraptora (P. domesticus + D. antirrhopus)
                    • Deinonychosauria
                      Deinonychosauria
                      The Deinonychosauria were a clade of coelurosaurian theropod dinosaurs from the Late Jurassic and Cretaceous periods. These omnivores and carnivores are known for their switchblade-like second toe claws and for displaying numerous bird-like characteristics. The clade has been divided into two...

                       (
                      D. antirrhopus > P. domesticus or Dromaeosaurus
                      Dromaeosaurus
                      Dromaeosaurus was a genus of theropod dinosaur which lived during the Late Cretaceous period , sometime between 76.5 and 74.8 million years ago, in the western United States and Alberta, Canada. The name means 'running lizard'....

                       albertensis + Troodon
                      Troodon
                      Troodon is a genus of relatively small, bird-like dinosaur from the Late Cretaceous period . Discovered in 1855, it was among the first dinosaurs found in North America...

                       formosus)
                      • Troodontidae
                        Troodontidae
                        Troodontidae is a family of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and scrappy and they have therefore been allied, at various times, with many dinosaurian lineages...

                         (
                        T. formosus > Velociraptor
                        Velociraptor
                        Velociraptor is a genus of dromaeosaurid theropod dinosaur that existed approximately 75 to 71 million years ago during the later part of the Cretaceous Period. Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis; fossils...

                         mongoliensis)
                      • Dromaeosauridae
                        Dromaeosauridae
                        Dromaeosauridae is a family of bird-like theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek dromeus meaning 'runner' and sauros meaning 'lizard'...

                         (
                        Microraptor
                        Microraptor
                        Microraptor is a genus of small, four-winged dromaeosaurid dinosaurs. Numerous well-preserved fossil specimens have been recovered from Liaoning, China...

                         zhaoianus + Sinornithosaurus
                        Sinornithosaurus
                        Sinornithosaurus is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999...

                         millenii + V. mongoliensis)
                    • Avialae
                      Avialae
                      Avialae is a clade of dinosaurs containing their only living representatives, birds , and the most immediate extinct relatives of birds.-Competing definitions:...

                       (
                      Archaeopteryx
                      Archaeopteryx
                      Archaeopteryx , sometimes referred to by its German name Urvogel , is a genus of theropod dinosaur that is closely related to birds. The name derives from the Ancient Greek meaning "ancient", and , meaning "feather" or "wing"...

                      + Neornithes)

Ornithischia


(
Iguanodon
Iguanodon
Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedal hypsilophodontids and the ornithopods' culmination in the duck-billed dinosaurs...

/Triceratops > Cetiosaurus/Tyrannosaurus)
  • ? Lesothosaurus
    Lesothosaurus
    Lesothosaurus is an herbivorous ornithischian dinosaur. It was named by paleontologist Peter Galton in 1978, the name meaning "lizard from Lesotho". The genus is monotypic, having only one valid species, Lesothosaurus diagnosticus, within the genus....

     diagnosticus
  • ? Heterodontosauridae
    Heterodontosauridae
    Heterodontosauridae is a family of early ornithischian dinosaurs that were likely among the most basal members of the group...

  • Genasauria
    Genasauria
    Genasauria is an extinct clade of beaked, herbivorous dinosaurs. The group was first named by paleontologist Paul Sereno in 1986, and is typically split into Thyreophora, a group of armored dinosaurs; and Neornithischia, which included the horned and duck-billed dinosaurs...

     (
    Ankylosaurus
    Ankylosaurus
    Ankylosaurus is a genus of ankylosaurid dinosaur, containing one species, A. magniventris...

    + Triceratops)
    • Thyreophora
      Thyreophora
      The Thyreophora were a subgroup of the ornithischian dinosaurs...

      (
      Ankylosaurus > Triceratops)
      • Scelidosauridae
      • Eurypoda (Ankylosaurus + Stegosaurus)
        • Stegosauria
          Stegosauria
          Known colloquially as stegosaurs, the Stegosauria are a group of herbivorous dinosaurs of the Jurassic and Early Cretaceous Periods, being found mostly in the Northern Hemisphere, predominantly in what is now North America and China....

           (
          Stegosaurus > Ankylosaurus)
          • Huayangosauridae (Huayangosaurus > Stegosaurus)
          • Stegosauridae
            Stegosauridae
            Stegosauridae is a family of stegosauria, large thyreophorans. They lived longer than other Stegosaurs; while all Huayangosauridae and most of basal stegosaurs died out in Tithonian - Kimmeridgian, stegosauridae survived till Middle Cretaceous. They are usually characterized by triangular plates on...

             (
            Stegosaurus > Huayangosaurus)
            • Dacentrurus
              Dacentrurus
              Dacentrurus , originally known as Omosaurus, was a large stegosaur of the Late Jurassic Period .-Description:...

               armatus
            • Stegosaurinae (Stegosaurus > Dacentrurus)
        • Ankylosauria
          Ankylosauria
          Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are first known to have appeared in the early Jurassic Period of...

           (
          Ankylosaurus > Stegosaurus)
          • Ankylosauridae
            Ankylosauridae
            An ankylosaurid is a member of the Ankylosauridae family of armored dinosaurs that evolved 125 million years ago and became extinct 65 million years ago during the Cretaceous-Tertiary extinction event...

             (
            Ankylosaurus > Panoplosaurus)
            • Gastonia
              Gastonia (dinosaur)
              Gastonia is a genus of nodosaurid dinosaur from the Early Cretaceous of North America, around 125 million years ago. Closely related to Polacanthus, it has a sacral shield and large shoulder spikes. It is also the first polacanthine dinosaur to have been mounted for display at the Denver Museum of...

               burgei
            • Shamosaurus
              Shamosaurus
              Shamosaurus is an extinct genus of basal ankylosaurid ankylosaur from Early Cretaceous deposits of Höövör, Mongolia. Shamosaurus is known from the holotype PIN N 3779/2 complete skull and jaw and the paratypes include partial skeleton remains and an armor. It was collected from the...

               scutatus
            • Ankylosaurinae (Ankylosaurus > Shamosaurus)
          • Nodosauridae
            Nodosauridae
            Nodosauridae is a family of ankylosaurian dinosaurs, from the Late Jurassic to the Late Cretaceous Period of what are now North America, Asia, Antarctica and Europe.-Characteristics:...

             (
            Panoplosaurus > Ankylosaurus)
    • Cerapoda
      Cerapoda
      Neornithischia is a clade of the dinosaur order Ornithischia. They are the sister group of the Thyreophora within the clade Genasauria. Neornithischians are united by having a thicker layer of asymmetrical enamel on the inside of their lower teeth...

      (
      Triceratops > Ankylosaurus)
      • Ornithopoda (Edmontosaurus
        Edmontosaurus
        Edmontosaurus is a genus of crestless hadrosaurid dinosaur. It contains two species: Edmontosaurus regalis and Edmontosaurus annectens. Fossils of E. regalis have been found in rocks of western North America that date from the late Campanian stage of the Cretaceous Period 73 million years ago,...

        > Triceratops)
        • ? Lesothosaurus
          Lesothosaurus
          Lesothosaurus is an herbivorous ornithischian dinosaur. It was named by paleontologist Peter Galton in 1978, the name meaning "lizard from Lesotho". The genus is monotypic, having only one valid species, Lesothosaurus diagnosticus, within the genus....

           diagnosticus
        • ? Heterodontosauridae
          Heterodontosauridae
          Heterodontosauridae is a family of early ornithischian dinosaurs that were likely among the most basal members of the group...

        • Euornithopoda
          • Hypsilophodon
            Hypsilophodon
            Hypsilophodon is an ornithopod dinosaur genus from the Early Cretaceous period of Europe. It was a small bipedal animal with an herbivorous or possibly omnivorous diet...

             foxii
          • Thescelosaurus
            Thescelosaurus
            Thescelosaurus was a genus of small ornithopod dinosaur that appeared at the very end of the Late Cretaceous period in North America. It was a member of the last dinosaurian fauna before the Cretaceous-Tertiary extinction event around 65.5 million years ago...

             neglectus
          • Iguanodontia (Edmontosaurus > Thescelosaurus)
            • Tenontosaurus
              Tenontosaurus
              Tenontosaurus is a genus of medium- to large-sized ornithopod dinosaur. The genus is known from the late Aptian to Albian ages of the middle Cretaceous period sediments of western North America, dating between 115 to 108 million years ago...

               tilletti
            • Rhabdodontidae
              Rhabdodontidae
              Rhabdodontids were herbivorous ornithopod dinosaurs from the Cretaceous Period. Rhabdodontids were similar to large, robust hypsilophodonts, with deep skulls and jaws. The family was first proposed by David B. Weishampel et al. in 2002...

            • Dryomorpha
              • Dryosauridae
                Dryosauridae
                Dryosaurids were primitive iguanodonts. They are known from Middle Jurassic to Early Cretaceous rocks of Africa, Europe, and North America.-Phylogeny:...

              • Ankylopollexia
                • Camptosauridae
                • Styracosterna
                  • Lurdusaurus
                    Lurdusaurus
                    Lurdusaurus is a genus of large ornithopod dinosaur which lived in the Aptian stage of the Early Cretaceous, sometime between 121 to 112 million years ago.-Discovery and naming:...

                     arenatus
                  • Iguanodontoidea (=Hadrosauriformes)
                    • Iguanodontidae
                    • Hadrosauridae (Telmatosaurus + Parasaurolophus
                      Parasaurolophus
                      Parasaurolophus is a genus of ornithopod dinosaur that lived in what is now North America during the Late Cretaceous Period, about 76.5–73 million years ago. It was an herbivore that walked both as a biped and a quadruped. Three species are recognized: P. walkeri , P. tubicen, and the...

                      )
                      • Telmatosaurus
                        Telmatosaurus
                        Telmatosaurus is a genus of basal hadrosaurid dinosaur from the Late Cretaceous. It was a relatively small hadrosaur, approximately five meters long, found in what is now Romania....

                         transsylvanicus
                      • Euhadrosauria
                        • Lambeosaurinae
                          Lambeosaurinae
                          Lambeosaurinae is a group of crested hadrosaurid dinosaurs.-Classification:Lambeosaurines have been split into Parasaurolophini and Corythosaurini . Corythosaurini and Parasaurolophini as terms entered the formal literature in Evans and Reisz's 2007 redescription of Lambeosaurus magnicristatus...

                        • Saurolophinae (=Hadrosaurinae
                          Hadrosaurinae
                          Saurolophinae is a subfamily of hadrosaurid dinosaurs. Members of the subfamily derive from the Late Cretaceous of Antarctica, Argentina, Canada , China, Kazakhstan, Mexico, Russia, the United States and...

                          )
      • Marginocephalia
        Marginocephalia
        Marginocephalia is a clade of ornithischian dinosaurs that includes the thick-skulled pachycephalosaurids, and horned ceratopsians. They were all herbivores, walking on two or four legs, and are characterized by a bony ridge or frill the back of the skull...

        • Pachycephalosauria
          Pachycephalosauria
          Pachycephalosauria is a clade of ornithischian dinosaurs. Well-known genera include Pachycephalosaurus, Stegoceras, Stygimoloch, and Dracorex. Most lived during the Late Cretaceous Period, in what is now North America and Asia. They were all bipedal, herbivorous/omnivorous animals with thick skulls...

           (
          Pachycephalosaurus
          Pachycephalosaurus
          Pachycephalosaurus is a genus of pachycephalosaurid dinosaur. It lived during the Late Cretaceous Period of what is now North America. Remains have been excavated in Montana, South Dakota, and Wyoming. It was an herbivorous or omnivorous creature which is only known from a single skull and a few...

           wyomingensis > Triceratops horridus)
          • Goyocephala (Goyocephale + Pachycephalosaurus)
            • Homalocephaloidea (Homalocephale
              Homalocephale
              Homalocephale is a genus of dinosaur belonging to the pachycephalosaurid family, which lived during the late Cretaceous period of what is now Mongolia, 80 million years ago. The genus was described in 1974 by Osmólska & Maryañska, and consists of a single species, H...

               + Pachycephalosaurus)
              • Homalocephalidae
              • Pachycephalosauridae
        • Ceratopsia
          Ceratopsia
          Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs which thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7...

           (Triceratops > Pachycephalosaurus)
          • Psittacosauridae
            Psittacosauridae
            The Psittacosauridae were a group of ceratopsian dinosaurs, which lived between 140.2 and 99.6 million years ago. The family Psittacosauridae was first named by American paleontologist Henry Fairfield Osborn in 1923...

          • Neoceratopsia
            • Coronosauria
              • Protoceratopsidae
              • Bagaceratopidae
                Bagaceratopidae
                Bagaceratopidae is a family of neoceratopsian dinosaurs. It was named by Alifanov in 2003 but no definition has been proposed. Because of lacking of the definition, Bagaceratopidae was considered inactive by Paul Sereno in 2005...

              • Ceratopsoidea
                • Leptoceratopsidae
                  Leptoceratopsidae
                  The family Leptoceratopsidae, its name derived from the type genus Leptoceratops, is a group of several small neoceratopsian genera which appear not to belong to the clade Protoceratopsidae. They resembled, and were closely related to, other ceratopsids, but all discovered species are generally...

                • Ceratopsomorpha
                  • Ceratopsidae
                    Ceratopsidae
                    Ceratopsidae is a speciose group of marginocephalian dinosaurs including Triceratops and Styracosaurus...

                    • Centrosaurinae
                      Centrosaurinae
                      The Centrosaurinae is a subfamily of ceratopsid dinosaurs named by paleontologist Lawrence Lambe, in 1915, with Centrosaurus as the type genus...

                    • Chasmosaurinae
                      Chasmosaurinae
                      Chasmosaurinae is a subfamily of ceratopsid dinosaurs. Triceratops is a well-known example. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non-avian dinosaurs, during the K-T extinction...