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Amazichthys
''Amazichthys'' is an Extinction, extinct genus of Selenosteidae, selenosteid Arthrodira, arthrodire from the Famennian, Middle Famennian of the Late Devonian of the Anti-Atlas, Anti-Atlas Mountains of Morocco. It contains a single species, ''Amazichthys trinajsticae''. It is one of a few example of Placodermi, placoderm known from whole body shape, including cartilaginous axial and fin elements. Description ''Amazichthys'' had a profile similar to that of fast-moving Pelagic fish, pelagic fishes, with lateral keels for stability, and a Caudal fin, lunate caudal fin, suggesting it could reach and maintain high speed. The holotype, AA.MEM.DS.8, is long. Etymology ''Amazichthys trinajsticae'' was named after the North African ethnic group Amazigh (Berbers), and Australian palaeontologist Kate Trinajstic. Taxonomy ''Amazichthys'' is part of Selenosteidae, a family inside the clade Aspinothoracidi, inside of Pachyosteomorphi, along with Dunkleosteoidea. The cladogram show ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenosteidae
Selenosteidae is an extinct family of small to large-sized arthrodire placoderms from the Late Devonian. With the exception of the Chinese '' Phymosteus'', selenosteids lived in shallow seas in what is now Eastern North America (the Cleveland Shale), Eastern Europe (Holy Cross Mountains, Poland, and the Kellwasserkalk fauna of Bad Wildungen), and Northeastern Africa (the Anti-Atlas Mountains, Morocco). Selenosteids have, in cross section, a rounded body, a blunt snout, and tremendous orbits. The lower jaws were slender, the inferognathals usually either being finely serrated, or adapted for crushing, though, in '' Draconichthys'', the inferognathals had long prongs for seizing prey. The rostrum is very small. Taxonomy Selenosteidae is a member of the clade Aspinothoracidi, which belongs to the clade Pachyosteomorphi, one of the two major clades within Eubrachythoraci. ''Gorgonichthys'' is closely related to the family Selenosteidae, and could possibly be included in the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthrodira
Arthrodira (Greek for "jointed neck") is an order of extinct armored, jawed fishes of the class Placodermi that flourished in the Devonian period before their sudden extinction, surviving for about 50 million years and penetrating most marine ecological niches. Arthrodires were the largest and most diverse of all groups of placoderms. Description Arthrodire placoderms are notable for the movable joint between armor surrounding their heads and bodies. Like all placoderms, they lacked distinct teeth; instead, they used the sharpened edges of a bony plate on their jawbone as a biting surface. The eye sockets are covered by a bony ring, which supports the eye, a feature shared by birds and some ichthyosaurs. Early arthrodires, such as the genus '' Arctolepis'', were well-armoured fishes with flattened bodies. The largest member of this group, ''Dunkleosteus'', was a true superpredator of the latest Devonian period, reaching as much as 6 m in length. In contrast, the long-nosed '' Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placodermi
Placoderms (from Ancient Greek πλάξ 'plax'', ''plakos''' plate' and δέρμα 'derma'''skin') are vertebrate animals of the class Placodermi, an extinct group of prehistoric fish known from Paleozoic fossils during the Silurian and the Devonian periods. While their endoskeletons are mainly cartilaginous, their head and thorax were covered by articulated armoured plates (hence the name), and the rest of the body was scaled or naked depending on the species. Placoderms were among the first jawed fish (their jaws likely evolved from the first pair of gill arches), as well as the first vertebrates to have true teeth. They were also the first fish clade to develop pelvic fins, the second set of paired fins and the homologous precursor to hindlimbs in tetrapods. 380-million-year-old fossils of three other genera, '' Incisoscutum'', '' Materpiscis'' and '' Austroptyctodus'', represent the oldest known examples of live birth. Placoderms are thought to be paraphyletic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunkleosteus
''Dunkleosteus'' is an extinct genus of large arthrodira, arthrodire ("jointed-neck") fish that existed during the Late Devonian period, about 382–358 million years ago. It was a pelagic fish inhabiting open waters, and one of the first vertebrate apex predators of any ecosystem. ''Dunkleosteus'' consists of ten species, some of which are among the largest placoderms ("plate-skinned") to have ever lived: ''D. terrelli'', ''D. belgicus'', ''D. denisoni'', ''D. marsaisi'', ''D. magnificus'', ''D. missouriensis'', ''D. newberryi'', ''D. amblyodoratus'', ''D. raveri'', and ''D. tuderensis.'' However, the validity of several of these species is unclear. The largest and best known species is ''D. terrelli''. Since body shape is not known, various methods of estimation put the living total length of the largest known specimen of ''D. terrelli'' between long and its weight around . Lengths of or more are poorly supported, with the most recent and extensive studies on the body shape a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latocamurus
''Latocamurus'' is an extinct monospecific genus of flat-nosed arthrodire placoderm from the Early Frasnian stage of the Late Devonian period, found at the Gogo Formation of Kimberley, Western Australia. Phylogeny ''Camuropiscis'' is a member of the family Camuropiscidae under 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 or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ... of ''Camuropiscis'': References Camuropiscidae {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camuropiscis
''Camuropiscis'' is an extinct genus of arthrodire placoderm from the Early Frasnian stage of the Late Devonian period, found at the Gogo Formation of Kimberley, Western Australia. The species of ''Camuropiscis'' had a flattened, elongated snout that may have aided in enhancing its hydrodynamic streamlining. Etymology ''Camuropiscis'' translates as "flat-nosed fish." Phylogeny ''Camuropiscis'' is a member of the family Camuropiscidae under 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 or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ... of ''Camuropiscis'': References Placoderm genera Camuropiscidae {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubonasus
''Tubonasus'' (meaning "tube nose") is an extinct monospecific genus of long-snouted arthrodire placoderm from the Early Frasnian stage of the Late Devonian period, found at the Gogo Formation of Kimberley, Western Australia. ''Tubonasus'' is interpreted as a pelagic pursuit predator, and had the ability of swallowing prey whole. Like other camuropiscids, it has an elongated rostrum, streamlined body, and narrow infragnathals. Phylogeny ''Tubonasus'' is a member of the family Camuropiscidae under 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 or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ... of ''Tubonasus'': References Camuropiscidae {{Placo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastmanosteus
''Eastmanosteus'' ("Eastman's bone") is a fossil genus of Dunkleosteidae, dunkleosteid placoderms. It was closely related to the giant ''Dunkleosteus'', but differed from that genus in size, in possessing a distinctive tuberculated bone ornament, a differently shaped nuchal plate and a more zig-zagging course of the sutures of the skull roof. Species of ''Eastmanosteus'' had powerful jaws with sharp cutting edges and were likely active predators. Fossils have been found in many parts of the world in marine sediments dating from the Middle to Late Devonian. They were medium-to-large fish, with specimens ''E. pustulosus'' and ''E. licharevi'' approaching a total length of 3 metres. Complete exoskeletons with soft-tissue traces of ''E. calliaspis'' from Australia make this one of the best known dunkleosteids. Phylogeny ''Eastmanosteus'' and its relative ''Dunkleosteus'' belong to the family (biology), family Dunkleosteidae. The phylogeny of ''Eastmanosteus'' can be shown in the clad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holonema
''Holonema'' is an extinct genus of relatively large, barrel-shaped arthrodire placoderms that were found in oceans throughout the world from the Mid to Late Devonian, when the last species perished in the Frasnian-Fammian extinction event. Most species of the genus are known from fragments of their armor, but the Gogo Reef species, ''H. westolli'', is known from whole, articulated specimens. Description ''Holonema'' is thought to have been a benthic-dwelling fish, based on its cambered body shape, which performs better hydrodynamically when closer to the sea bed. Although previously thought to have fed in the bottom seafloor mud, more recent morphological studies of the jaw and toothplates suggest a more planktivorous lifestyle. ''Holonema'' fossil individuals have small stones in the trunk shield, and pieces of feldspar in the abdominal region, suggesting ''Holonema'' used these as gastroliths for processing food. Species ''H. rugosum'' ''H. rugosum'' is the type specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisoscutum
''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 ichthyology, 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, Compagopiscis croucheri'' and the more derived species ''Incisoscutum ritchiei'' suggested that lengthwise growth occurs earlier in the ontogeny than growth in width, and that di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mcnamaraspis
''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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compagopiscis
''Compagopiscis'' is an extinct genus of placoderm known from the Gogo Formation. It lived in the Upper Devonian (Frasnian stage) of Western Australia. The genus is monotypic, with its only species being ''Compagopiscis croucheri''. Description ''Compagopiscis'' is one of the earliest known vertebrates to have teeth. An analysis of its bite force suggests that it was a generalist predator, having a diverse diet. Fossils have been found in numbers, suggesting possible schooling behavior. Phylogeny ''Compagopiscis'' was originally classified as a member of the family Plourdosteidae. However, phylogenetic analysis later found Plourdosteidae to be an invalid grouping, and the family was dismissed. ''Torosteus'' is now considered to be 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 or phylogeny is a graphical representati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
