The Poposauridae are a family of large (around 2.5 to 5 meters long) carnivorous archosaurs which lived alongside dinosaurs during the Late Triassic. They are known from fossil remains from North America and Europe, and constituted the apex predators in a number of environments. Originally believed to be theropod dinosaurs (they mirrored the theropods in a number of respects, such as features of the skull), cladistic analysis has shown them to be related to crocodiles. The Carnian is a stage on the geologic time scale occuring from 228 +/- 2 to 216. ... The Rhaetian Stage is the most recent stage of the Late Triassic. ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms (as opposed to folk taxonomy). ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (rhombozoans) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Orthonectida (parasitic to flatworms, echinoderms, etc. ... Typical Classes Subphylum Urochordata - Tunicatas Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Clades Subclass Anapsida Subclass Diapsida Infraclass Lepidosauromorpha Infraclass Archosauromorpha Sauropsida is an amniote clade that includes all recent and all or almost all extinct reptiles (excluding the Synapsida), and birds. ... Groups See Text Diapsids (two arches) are a group of tetrapod animals that developed two holes (temporal fenestra) in each side of their skulls, about 300 million years ago during the late Carboniferous period. ... Groups Archosaurus Chasmatosaurus Euparkeria Crurotarsi     Aetosauria     Crocodilia (crocodiles)     Phytosauria     Rauisuchia Ornithodira     Pterosauria     Marasuchus     Dinosauria        Aves (birds) Archosaurs (Greek for ruling reptiles) are a group of diapsid reptiles that first evolved from Archosauriform ancestors during the Olenekian (Lower Triassic). ... Subtaxa Phytosauridae Prestosuchidae Ornithosuchidae Stagonolepididae Rauisuchidae Poposauridae Crocodylomorpha     Sphenosuchia     Crocodilia Crurotarsi (cross-ankles) is a node-based taxon created by Paul Sereno in 1991 to supplant the old term Pseudosuchia. ... Groups Family Prestosuchidae Family Rauisuchidae Family Poposauridae Rauisuchia are a poorly known assemblage of predatory and mostly large (often 4 to 6 meters) Triassic archosaurs. ... 1923 (MCMXXIII) was a common year starting on Monday (link will take you to calendar). ... In biology, a genus (plural genera) is a taxonomic grouping. ... A Postosuchus from Walking with Dinosaurs Postosuchus was a basal archosaur (ruling lizard) which lived in what is now North America during the end of the Triassic period (220-205 million years ago). ... Shuvosaurus (Shuvos reptile) was reported as a theropod dinosaur from Triassic Texas. ... Teratosaurus was a genus of rauisuchian from the Triassic Period. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... The lion is a well-known, truly carnivorous member of the order Carnivora. ... Groups Archosaurus Chasmatosaurus Euparkeria Crurotarsi     Aetosauria     Crocodilia (crocodiles)     Phytosauria     Rauisuchia Ornithodira     Pterosauria     Marasuchus     Dinosauria        Aves (birds) Archosaurs (Greek for ruling reptiles) are a group of diapsid reptiles that first evolved from Archosauriform ancestors during the Olenekian (Lower Triassic). ... The Triassic is a geologic period that extends from about 245 to 202 Ma (million years ago). ... It has been suggested that this article or section be merged into Predator and prey. ... Families See text Theropods (beast foot) are a group of bipedal, primarily carnivorous dinosaurs, belonging to the saurischian (lizard-hip) family. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... This cladogram shows the relationship among various insect groups. ... Subfamilies Family Crocodylidae    Crocodylinae    Alligatorinae    Gavialinae Crocodylia (or crocodylians) is an order of large reptiles that scientists believe branched off from class Reptilia about 220 million years ago. ...

Despite the genus Postosuchus appearing in the documentary series Walking With Dinosaurs, the group is still poorly known, although it is thought that recent description and discoveries of genera such as Sillosuchus and Shuvosaurus will improve our understanding of these animals and their phylogenetic relationships within the Crurotarsi. A Postosuchus from Walking with Dinosaurs Postosuchus was a basal archosaur (ruling lizard) which lived in what is now North America during the end of the Triassic period (220-205 million years ago). ... Walking with Dinosaurs is a 1999 six-part television series produced by the BBC, narrated by Kenneth Branagh. ... Shuvosaurus (Shuvos reptile) was reported as a theropod dinosaur from Triassic Texas. ... In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... Subtaxa Phytosauridae Prestosuchidae Ornithosuchidae Stagonolepididae Rauisuchidae Poposauridae Crocodylomorpha     Sphenosuchia     Crocodilia Crurotarsi (cross-ankles) is a node-based taxon created by Paul Sereno in 1991 to supplant the old term Pseudosuchia. ...

References

• Galton, P. M., 1985, The poposaurid thecodontian Teratosaurus suevicus von Meyer, plus referred specimens mostly based on prosauropod dinosaurs. Stuttgarter Beitrage zur Naturkunde, B, v. 116, p. 1-29.
• Lucas, SG (1998), Global Triassic tetrapod biostratigraphy and biochronology. Palaeogeog. Palaeoclimatol., Palaeoecol. 143: 347-384.
• Parrish, JM (1993), Phylogeny of the Crocodylotarsi, with reference to archosaurian and crurotarsan monophyly. J. Vert. Paleontol. 13: 287-308.

Spencer G. Lucas is a paleontologist and stratigrapher, and curator of paleontology at the New Mexico Museum of Natural History and Science. ...

External links

• Palaeos
• Taxon Search
• Mikko's Phylogeny Archive