Archichthys Temporal range: Carboniferous | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Sarcopterygii |
Clade: | Tetrapodomorpha |
Class: | † Rhizodontida |
Order: | † Rhizodontiformes |
Family: | † Rhizodontidae |
Genus: | † Archichthys Hancock and Atthey, 1870 |
Type species | |
†Archichthys portlockii Portlock, 1843 | |
Synonyms | |
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Archichthys is a genus of rhizodont lobe-finned fish that lived throughout the Carboniferous period. Fossils have been found in Northern Ireland and England. [1]
The Carboniferous is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period 358.9 Ma to the beginning of the Permian Period, 298.9 Ma. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian.
The Devonian is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at 419.2 million years ago (Ma), to the beginning of the succeeding Carboniferous period at 358.9 Ma. It is named after Devon, South West England, where rocks from this period were first studied.
The PaleozoicEra is the first of three geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic and ends 251.9 Ma at the start of the Mesozoic Era. The Paleozoic is subdivided into six geologic periods :
"Labyrinthodontia" is an informal grouping of extinct predatory amphibians which were major components of ecosystems in the late Paleozoic and early Mesozoic eras. Traditionally considered a subclass of the class Amphibia, modern classification systems recognize that labyrinthodonts are not a formal natural group (clade) exclusive of other tetrapods. Instead, they consistute an evolutionary grade, ancestral to living tetrapods such as lissamphibians and amniotes. "Labyrinthodont"-grade vertebrates evolved from lobe-finned fishes in the Devonian, though a formal boundary between fish and amphibian is difficult to define at this point in time.
Romer's gap is an apparent gap in the Paleozoic tetrapod fossil record used in the study of evolutionary biology, which represent periods from which excavators have not yet found relevant fossils. It is named after American paleontologist Alfred Romer, who first recognised it in 1956. Recent discoveries in Scotland are beginning to close this gap in palaeontological knowledge.
Canobius is an extinct genus of early marine ray-finned fish that lived in the early Carboniferous period (Viséan) of Glencartholm, Scotland.
Rhizodus is an extinct genus of basal, finned tetrapodomorphs. It belonged to Rhizodontida, one of the earliest-diverging tetrapodomorph clades. Two valid species have been described, both of which lived during the Early Carboniferous epoch. The type species R. hibberti is known from the Viséan stage of the United Kingdom, whereas the species R. serpukhovensis is from the Serpukhovian of Russia. Some fossils referred to the genus Rhizodus have also been found in North America.
Pederpes is an extinct genus of early Carboniferous tetrapod, dating from 348 to 347.6 Ma in the Tournaisian age. Pederpes contains one species, P. finneyae, 1 m long.
Allenypterus is an extinct genus of coelacanths which lived during the Bashkirian age of the Late Carboniferous period, 318 million years ago). Fossils have been discovered in Bear Gulch Limestone, Montana, USA.
Rhabdoderma is an extinct genus of coelacanth fish in the class Sarcopterygii. It lived in the Carboniferous and Early Triassic (Induan), and its fossils have been found in Europe, Madagascar and North America. The type species was originally described as Coelacanthus elegans. Five species are considered valid in 1981.
Strepsodus is a genus of rhizodont lobe-finned fish that lived throughout the Carboniferous period. Fossils have been found in eastern Canada, Britain, and Queensland, Australia; indeterminate species of Strepsodus have also been found in the late Devonian deposits of Turkey, Iran and Colombia. A large individual is measured up to 3.5 metres (11.5 ft) long.
Barameda is a genus of rhizodont lobe-finned fishes which lived during the Tournaisian stage near the start of the Carboniferous period in Australia; fossils of the genus have been reported from the Snowy Plains Formation. The largest member of this genus, Barameda decipiens, reached an estimated length of around 3–4 metres (9.8–13.1 ft), while the smallest species, B. mitchelli is estimated to have had a length of about 35 centimetres (14 in).
Caridosuctor is an extinct genus of marine coelacanth that lived during the Carboniferous period. It contains a single species, C. populusum, with fossils known from the Bear Gulch Limestone in Montana.
Cheirodopsis is an extinct genus of prehistoric marine ray-finned fish that lived during the Viséan stage of the Mississippian epoch. It contains a single species, C. geikiei from what is now Glencartholm, Scotland.
Sundayichthys is an extinct genus of prehistoric bony fish that lived during the Carboniferous period in what is now South Africa. Fossils were recovered from the Upper Witteberg Series.
Paleontology in Georgia refers to paleontological research occurring within or conducted by people from the U.S. state of Georgia. During the early part of the Paleozoic, Georgia was largely covered by seawater. Although no major Paleozoic discoveries have been uncovered in Georgia, the local fossil record documents a great diversity of ancient life in the state. Inhabitants of Georgia's early Paleozoic sea included corals, stromatolites, and trilobites. During the Carboniferous local sea levels dropped and a vast complex of richly vegetated delta formed in the state. These swampy deltas were home to early tetrapods which left behind footprints that would later fossilize. Little is known of Triassic Georgia and the Jurassic is absent altogether from the state's rock record. During the Cretaceous, however, southern Georgia was covered by a sea that was home to invertebrates and fishes. On land, the tree Araucaria grew, and dinosaurs inhabited the state. Southern Georgia remained submerged by shallow seawater into the ensuing Paleogene and Neogene periods of the Cenozoic era. These seas were home to small coral reefs and a variety of other marine invertebrates. By the Pleistocene the state was mostly dry land covered in forests and grasslands home to mammoths and giant ground sloths. Local coal mining activity has a history of serendipitous Carboniferous-aged fossil discoveries. Another major event in Georgian paleontology was a 1963 discovery of Pleistocene fossils in Bartow County. Shark teeth are the Georgia state fossil.
The fossilized remains of fish eggs have an extensive record going at least as far back as the Devonian and spanning into the Cenozoic era. The eggs of many different fish taxa have contributed to this record, including lobe-finned fish, placoderms, and sharks. Occasionally eggs are preserved still within the mother's body, or associated with fossil embryos. Some fossil eggs possibly laid by fish cannot be confidently distinguished from those laid by amphibians; for example, the ichnogenus Mazonova is known from impressions of eggs which resemble eggs of both fish and amphibians. Paleontologist B.K. Hall has observed that the discovery of fossil fish eggs, embryos and larvae link the sciences of paleontology with evo-devo.
The Ballagan Formation is a geologic formation in Scotland and England. It preserves fossils dating back to the early part of the Carboniferous period. Its name comes from the "Ballagan Beds" of Ballagan Glen, near Strathblane, which has a good example of this geological formation.
Cladodus is an extinct genus of cartilaginous fishes in the family Ctenacanthidae. As the name implies, they are a type of cladodont, primitive sharks with teeth designed to snag fish and swallow them whole, instead of sawing off chunks to swallow.
The Ganigobis Formation is a Late Carboniferous (Gzhelian) to Early Permian (Artinskian) geologic formation of the Dwyka Group in the ǁKaras Region of southeastern Namibia and the Northern Cape of South Africa. The widespread formation was deposited in the Aranos and Karoo Basins of southern Africa.