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Panxiosteidae
Panxiosteidae is an extinct family of arthrodire placoderms that lived during the Devonian period. Phylogeny The family Panxiosteidae was erected by Wang in 1979. Members of the family are noted for showing morphologically intermediate traits between coccosteids and dunkleosteids. In the 2010 Carr & Hlavin phylogenetic study, Panxiosteidae was recognized as the sister taxon to the family Dunkleosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). The phylogeny of Panxiosteidae from the 2013 Zhu & Zhu study is shown in the cladogram below: However, the subsequent 2016 Zhu ''et al.'' study using a larger morphological dataset recovered Panxiosteidae well outside of Dunkleosteoidea, instead within Coccosteomorphi and then Coccosteoidea as the sister group of Coccosteidae Coccosteidae is a family of arthrodire placoderms from the Early to Late Devonian. Fossils appear in various strata in Europe, North Ame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plourdosteus
''Plourdosteus'' is an extinct genus of placoderm arthrodire which was relatively widespread in Euramerica during the Givetian to Frasnian ages of the Devonian. Etymology The name ''Plourdosteus'' commemorates the Plourde family at Miguasha National Park. Taxonomy ''Plourdosteus'' was previously assigned to the family Plourdosteidae within the Coccosteomorphi. However, subsequent studies found the family Plourdosteidae to be polyphyletic and should be dismissed. ''Plourdosteus'' was then proposed to be a member of Panxiosteidae. In the 2010 Carr & Hlavin phylogenetic study, Panxiosteidae was recognized as the sister taxon to the family Dunkleosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). The phylogeny of ''Plourdosteus'' within Panxiosteidae is shown in the cladogram below from the 2013 Zhu & Zhu study: However, the subsequent 2016 Zhu ''et al.'' study using a larger morphological dataset recovered Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Janiosteus
''Janiosteus'' is an extinct monospecific genus of placoderm arthrodire from the Middle Devonian: Late Givetian stage found in Timan, Russia. Phylogeny ''Janiosteus'' is a member of Panxiosteidae. In the 2010 Carr & Hlavin phylogenetic study, Panxiosteidae was recognized as the sister taxon to the family Dunkleosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). The phylogeny of ''Janiosteus'' within Panxiosteidae is shown in the cladogram below from the 2013 Zhu & Zhu study: However, the subsequent 2016 Zhu ''et al.'' study using a larger morphological dataset recovered Panxiosteidae well outside of Dunkleosteoidea, instead within Coccosteomorphi and then Coccosteoidea as the sister group of Coccosteidae Coccosteidae is a family of arthrodire placoderms from the Early to Late Devonian. Fossils appear in various strata in Europe, North America and China. Phylogeny Coccosteidae belongs to the larger clade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panxiosteus
''Panxiosteus'' is an extinct monospecific genus of placoderm arthrodire from the Middle Devonian: Givetian stage of Yunnan province, China. Phylogeny ''Panxiosteus'' is a member of Panxiosteidae. In the 2010 Carr & Hlavin phylogenetic study, Panxiosteidae was recognized as the sister taxon to the family Dunkleosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). The phylogeny of ''Panxiosteus'' within Panxiosteidae is shown in the cladogram below from the 2013 Zhu & Zhu study: However, the subsequent 2016 Zhu ''et al.'' study using a larger morphological dataset recovered Panxiosteidae well outside of Dunkleosteoidea, instead within Coccosteomorphi and then Coccosteoidea as the sister group of Coccosteidae Coccosteidae is a family of arthrodire placoderms from the Early to Late Devonian. Fossils appear in various strata in Europe, North America and China. Phylogeny Coccosteidae belongs to the larger clade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunkleosteoidea
Dunkleosteoidea is an extinct superfamily of arthrodire placoderms that lived during the Devonian period. The gigantic apex predator ''Dunkleosteus terrelli'' is the best known member of this group. Phylogeny Eubrachythoraci is divided into the clades Coccosteomorphi and Pachyosteomorphi, the latter of which can be further sub-divided into Aspinothoracidi and Dunkleosteoidea. Dunkleosteoidea was then considered to consist of the two sister families Dunkleosteidae and Panxiosteidae. However, the 2016 Zhu ''et al.'' phylogenetic study using a larger morphological dataset recovered Panxiosteidae well outside of Dunkleosteoidea, leaving the status of Dunkleosteidae Dunkleosteidae is an extinct family of arthrodire placoderms that lived during the Devonian period. The gigantic apex predator ''Dunkleosteus terrelli'' is the best known member of this group. Phylogeny While members of Dunkleosteidae were prev ... as a clade grouping separate from Dunkleosteoidea in doubt, as shown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunkleosteidae
Dunkleosteidae is an extinct family of arthrodire placoderms that lived during the Devonian period. The gigantic apex predator ''Dunkleosteus terrelli'' is the best known member of this group. Phylogeny While members of Dunkleosteidae were previously thought to be close relatives of the genus ''Dinichthys'' (when they were not synonymized as each other) and grouped together in the family Dinichthyidae, more recent phylogenetic studies have shown that the two taxa represent two very distinct clades within Arthrodira. Dunkleosteidae was then established as the sister taxon to the family Panxiosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). Dunkleosteidae was thus cladistically defined as including the type genus ''Dunkleosteus'' and all other genera in Dunkleosteoidea more closely related to ''Dunkleosteus'' than to '' Panxiosteus''. The phylogeny of Dunkleosteidae from the 2013 Zhu & Zhu study is shown in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunkleosteids
Dunkleosteidae is an extinct family of arthrodire placoderms that lived during the Devonian period. The gigantic apex predator ''Dunkleosteus terrelli'' is the best known member of this group. Phylogeny While members of Dunkleosteidae were previously thought to be close relatives of the genus ''Dinichthys'' (when they were not synonymized as each other) and grouped together in the family Dinichthyidae, more recent phylogenetic studies have shown that the two taxa represent two very distinct clades within Arthrodira. Dunkleosteidae was then established as the sister taxon to the family Panxiosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). Dunkleosteidae was thus cladistically defined as including the type genus ''Dunkleosteus'' and all other genera in Dunkleosteoidea more closely related to ''Dunkleosteus'' than to ''Panxiosteus''. The phylogeny of Dunkleosteidae from the 2013 Zhu & Zhu study is shown in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccosteomorphi
Coccosteomorphi is an extinct clade of arthrodire placoderms within the Eubrachythoraci (of the suborder Brachythoraci), armored fish most diverse during the Devonian. Most are considered to be pelagic (open ocean) long-distance swimmers, leading to their widespread distribution beginning from at least the Middle Devonian period. Phylogeny Coccosteomorphi is the sister taxon to Pachyosteomorphi, which together are the two main sub-clades of Eubrachythoraci. Coccosteomorphi can be further sub-divided into Coccosteoidea and Incisoscutoidea, as shown in the cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... below: References Arthrodires {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eubrachythoraci
Eubrachythoraci is an extinct clade of arthrodire placoderms within the suborder Brachythoraci, armored fish most diverse during the Devonian. Most are considered to be pelagic (open ocean) long-distance swimmers, leading to their widespread distribution beginning from at least the Middle Devonian period. Phylogeny Brachythoraci is divided into the large derived clade Eubrachythoraci and several basal groups: Buchanosteoidea, Homosteidae, and Holonematidae. (Although Holonematidae's membership in Brachythoraci is disputed.) Eubrachythoraci is then further divided into the sub-clades Coccosteomorphi and Pachyosteomorphi, the latter of which can be further sub-divided into Aspinothoracidi and Dunkleosteoidea, as shown in the cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coccosteids
Coccosteidae is a family of arthrodire placoderms from the Early to Late Devonian. Fossils appear in various strata in Europe, North America and China. Phylogeny Coccosteidae belongs to the larger clade Coccosteomorphi, which together with its sister clade Pachyosteomorphi forms the group Eubrachythoraci. The phylogeny of Coccosteidae can be shown in the cladogram below: Genera '' Belgiosteus'' A genus of very large coccosteids. Species are found in Middle Devonian Belgium and China. '' Clarkosteus'' ''Coccosteus'' The type genus of the family. Numerous species are found in Middle to Upper Devonian strata throughout Europe and parts of North America. ''Dickosteus'' ''Jiuchengia'' The earliest known coccosteid from Late Emsian Yunnan province, China. It is distinguished from other coccosteids by having an elongated occipital. '' Livosteus'' A genus of very large coccosteids known from Middle to Late Devonian strata of Eastern Europe. ''Millerosteus'' A genus of very smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisoscutum Ritchiei
''Incisoscutum'' is an extinct genus of arthrodire placoderm from the Early Frasnian Gogo Reef, from Late Devonian Australia. The genus contains two species ''I. ritchiei'', named after Alex Ritchie, a palaeoichthyologist and senior fellow of the Australian Museum, and ''I. sarahae'', named after Sarah Long, daughter of its discoverer and describer, John A. Long. The genus is important in the study of early vertebrates as well-preserved fossilized embryos have been found in female specimens and ossified pelvic claspers found in males. This shows that viviparity and internal fertilization was common amongst these primitive jawed vertebrates, which are outside the crown group Gnathostomata. In a study of fossil remains, comparison of the ontogeny of fourteen dermal plates from '' Compagopiscis croucheri'' and the more derived species ''Incisoscutum ritchiei'' suggested that lengthwise growth occurs earlier in the ontogeny than growth in width, and that dissociated allometric hete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harrytoombsia Elegans
''Harrytoombsia'' is an extinct genus of arthrodire placoderm from the Early Frasnian stage of the Late Devonian period. Fossils are found from Kimberley, Australia. It was a fast-swimming predator, and it had sharp blades of enamel-like material around the outer edge of the jaw for catching prey. Phylogeny ''Harrytoombsia'' is a member of the superfamily Incisoscutoidea, which belongs to the clade Coccosteomorphi, one of the two major clades within Eubrachythoraci. The cladogram below shows the phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ... of ''Harrytoombsia'': References Arthrodires Fossil taxa described in 1979 {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mcnamaraspis Kaprios
''Mcnamaraspis'' is an extinct monospecific genus of arthrodire placoderm that inhabited the ancient reef system of north Western Australia during the Frasnian epoch of the Late Devonian period (c. 380-375 million years ago). The type specimen was found and described by John A. Long from the Gogo Formation near Fitzroy Crossing. This fossil fish showed new anatomical features in arthrodires, like the well-preserved annular (ring-shaped) cartilages of the snout, previously inferred to be present by Erik Stensiö of Sweden. It is occasionally referred to as "The Gogo Fish" after the locale the holotype was excavated from. On 5 December 1995, the type species, ''M. kaprios'', was officially proclaimed as the State Fossil emblem of Western Australia by the Governor of Western Australia, thus becoming the first official state fossil emblem for any state of Australia. Description ''M. kaprios'' is an extinct marine fish that grew up to in length. With its large eyes, articulated ja ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
