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Phyllolepididae
Phyllolepididae is one of two families of phyllolepid placoderms. The family, as a whole, is believed to be descended from the Chinese placoderm, '' Gavinaspis ''(which forms the other, monotypic family, "Gavinaspididae"). All but two genera are, more or less, restricted to freshwater habitats of the Early to Middle Devonian of Australia. By the Frasnian, the genus '' Placolepis'' would spread throughout the world, with fossils being found in Australia, Turkey, Venezuela, and Antarctica, and by the start of the Famennian, phyllolepids would become extinct in Australia (then eastern Gondwana), with only species of ''Phyllolepis'' surviving in freshwater environments of Europe and North America. With the exception of ''Yurammia''. all phyllolepids have distinct ornamentation consisting primarily of concentric rings. Genera ''Phyllolepis'' The type genus is restricted to freshwater Famennian strata of Europe and North America. It is also the youngest genus of phyllolepid, be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllolepis
''Phyllolepis'' (from the Greek roots for ‘leaf’ and ‘scale’)Murphy, Dennis C. 4..20.2016. “Phyllolepis rossimontia (placoderm).” ''Devonian'' Times. is the type genus of Phyllolepida, an extinct taxon of arthrodire placoderm fish from the middle to late Devonian.“The life and times of Phyllolepis.” ''Phyllolepida''. Palaeos.com. 2005 The species of ''Phyllolepis'', themselves, are restricted to the Famennian-aged freshwater strata of the Late Devonian, around 360 million years ago. Fossils of this genus have been found primarily in Europe and North America. The end of the Devonian saw them disappear in a mass extinction. ''Phyllolepis'' lived in freshwater environments, possibly rivers and streams. As with all other known phyllolepids, ''Phyllolepis'' were presumed to have been blind, bottom-dwelling predators that detected prey through sensory organs in the surface grooves of their armor plates (which gave their plates a distinctive "wooden surface" appe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllolepids
Phyllolepida ("leaf scales") is an extinct taxon of flattened placoderms found throughout the world, with fossils being found in Devonian strata. Like other flattened placoderms, the phyllolepids were bottom-dwelling predators that ambushed prey. Unlike other flattened placoderms, the phyllolepids were inhabitants of freshwater environments. Unlike the Rhenanida, the armor of the phyllolepids were made of whole plates, rather than numerous tubercles and scales, and unlike the Petalichthyida, the components of the comparatively wide mouth are known. The phyllolepids are considered to have been blind, as the orbits for the eyes are extremely small, so much so as to suggest that the eyes were vestigial, and that they were placed on the sides of the head, as opposed to visually-oriented bottom-dwelling predators, like, say stargazers or flatfish, which have the eyes placed high on top of the head. Despite having a relatively clear idea of the phyllolepids' lifestyle and anatomy, mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yurammia
''Yurammia'' is a placoderm from what is now the Pambula River in New South Wales. Unlike all other known phyllolepids Phyllolepida ("leaf scales") is an extinct taxon of flattened placoderms found throughout the world, with fossils being found in Devonian strata. Like other flattened placoderms, the phyllolepids were bottom-dwelling predators that ambushed prey. ..., ''Yurammias plates had no external grooves. References Phyllolepids Placoderms of Antarctica {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austrophyllolepis
''Austrophyllolepis ''is an extinct genus of phyllolepid arthrodire placoderm from Middle to Late Devonian freshwater strata of Australia. The type species, ''A. ritchiei'' is found in Givetian to early Frasnian-aged freshwater strata near what is now Mount Howitt. A second species, ''A. dulciensis'', is found from Middle Devonian freshwater strata from the Dulcie Sandstone of Georgina Basin The Georgina Basin is a large (c. 330,000 km2) intracratonic sedimentary basin in central and northern Australia, lying mostly within the Northern Territory and partly within Queensland.Smith, KG (1972). "Stratigraphy of the Georgina Basin ..., Central Australia. References A New Phyllolepid Placoderm Occurrence (Devonian Fish) from the Dulcie Sandstone, Georgina Basin, Central Australia. Placoderms of Australia Phyllolepids Fossil taxa described in 1984 {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobandrahlepis
''Cobandrahlepis'' is an extinct genus of phyllolepid placoderm found in New South Wales, Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma .... References Placoderms of Australia Phyllolepids Fossil taxa described in 2005 {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cowralepis
''Cowralepis'' is an extinct genus of phyllolepid Phyllolepida ("leaf scales") is an extinct taxon of flattened placoderms found throughout the world, with fossils being found in Devonian strata. Like other flattened placoderms, the phyllolepids were bottom-dwelling predators that ambushed prey. ... placoderm of Givetian Cowra, New South Wales, and several juveniles of various stages of growth have also been discovered. References Placoderms of Australia Phyllolepids Fossil taxa described in 2005 {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placolepis
''Placolepis'' is an extinct genus of phyllolepid placoderm first discovered in New South Wales. ''Placolepis'' was the most widespread phyllolepid genus, with fossils found in Australia, Turkey, Venezuela and Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest co .... References Phyllolepids Placoderms of Europe Placoderms of Australia Placoderms of North America Placoderms of Antarctica {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Famennian
The Famennian is the latter of two faunal stages in the Late Devonian Epoch. The most recent estimate for its duration estimates that it lasted from around 371.1 million years ago to 359.3 million years ago. An earlier 2012 estimate, still used by the International Commission on Stratigraphy, estimated that it lasted from million years ago to million years ago. It was preceded by the Frasnian stage and followed by the Tournaisian stage. Major events In the seas, a novel major group of ammonoid cephalopods called clymeniids appeared, underwent tremendous diversification and spread worldwide, then just as suddenly went extinct. The beginning of the Famennian is marked by the final stages of a major extinction event, the Kellwasser Event, which is the largest component of the Late Devonian Mass extinction. The end of the Famennian experiences a smaller but still quite severe extinction event, the Hangenberg Event. A brief episode of glaciation, possibly linked to the Han ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages of break-up, involving the separation of Antarctica from South America (forming the Drake Passage) and Australia, occurred during the Paleogene. Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. To differentiate it from the Indian region of the same name (see ), it is also commonly called Gondwanaland. Gondwana was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Palaeozoic Era, covering an area of about , about one-fifth of the Earth's surface. During the Carboniferous Period, it merged with Laurasia to form a larger supercontinent called Pangaea. Gondwana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began domina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
