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Falcatus
''Falcatus'' is an extinct genus of falcatid chondrichthyan which lived during the early Carboniferous Period in Bear Gulch bay in what is now Montana. Description This fish was quite small, only getting to around 25–30 cm or 10-12 inches long. This is about as big as some of the smallest sharks around today, like the pygmy laternshark. Falcatus was a chondricthian known as a "cladodont-toothed stethacanthid holocephalan". The first material known from the genus were the prominent fin spines that curve anteriorly over the head of the animal. When first described in 1883 from the St. Louis Limestone, these remains were given the name ''Physonemus falcatus''. However, in 1985, fossils of a new type of condrichthyan from Montana were described that displayed a high degree of sexual dimorphism. The same spines that were previously named ''P. falcatus'' were found on one of the morphs, identified as the male due to the presence of valvae.The morphology of ''Falcatus fal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcatus Falcatus 01
''Falcatus'' is an extinct genus of falcatid chondrichthyan which lived during the early Carboniferous Period in Bear Gulch bay in what is now Montana. Description This fish was quite small, only getting to around 25–30 cm or 10-12 inches long. This is about as big as some of the smallest sharks around today, like the pygmy laternshark. Falcatus was a chondricthian known as a "cladodont-toothed stethacanthid holocephalan". The first material known from the genus were the prominent fin spines that curve anteriorly over the head of the animal. When first described in 1883 from the St. Louis Limestone, these remains were given the name ''Physonemus falcatus''. However, in 1985, fossils of a new type of condrichthyan from Montana were described that displayed a high degree of sexual dimorphism. The same spines that were previously named ''P. falcatus'' were found on one of the morphs, identified as the male due to the presence of valvae.The morphology of ''Falcatus fal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcatus
''Falcatus'' is an extinct genus of falcatid chondrichthyan which lived during the early Carboniferous Period in Bear Gulch bay in what is now Montana. Description This fish was quite small, only getting to around 25–30 cm or 10-12 inches long. This is about as big as some of the smallest sharks around today, like the pygmy laternshark. Falcatus was a chondricthian known as a "cladodont-toothed stethacanthid holocephalan". The first material known from the genus were the prominent fin spines that curve anteriorly over the head of the animal. When first described in 1883 from the St. Louis Limestone, these remains were given the name ''Physonemus falcatus''. However, in 1985, fossils of a new type of condrichthyan from Montana were described that displayed a high degree of sexual dimorphism. The same spines that were previously named ''P. falcatus'' were found on one of the morphs, identified as the male due to the presence of valvae.The morphology of ''Falcatus fal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bear Gulch Limestone
The Bear Gulch Limestone is a limestone-rich geological lens in central Montana, renowned for the quality of its late Mississippian-aged fossils. It is exposed over a number of outcrops northeast of the Big Snowy Mountains, and is often considered a component of the more widespread Heath Formation. The Bear Gulch Limestone reconstructs a diverse, though isolated, marine ecosystem which developed near the end of the Serpukhovian age. It is a lagerstätte, a particular type of rock unit with exceptional fossil preservation of both articulated skeletons and soft tissues. Bear Gulch fossils include a variety of fish, invertebrates, and algae occupying a number of different habitats within a preserved shallow bay. Fish include a high diversity of unusual Chondrichthyes, chondrichthyans (cartilaginous fish) and one of the oldest known lampreys, along with other vertebrates. Invertebrates include numerous fossils of crustaceans, worms, cephalopods, and Sponge, sea sponges, which are con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcatidae
Falcatidae is a family of Paleozoic holocephalians. Members of this family include ''Falcatus'', a small fish from the Bear Gulch Limestone of Montana. The family first appeared around the start of the Carboniferous, and there is some evidence that they survived well into the early Cretaceous, though its putative Cretaceous members were also argued to be more likely neoselachians. Genera *'' Denaea'' Ginter, M., Hampe., Duffin, C. 2010. Handbook of Paleoichthyology: Volume 3D- Paleozoic Elasmobranchii teeth. Verlag Dr. Freidrich Pfeil *''Falcatus'' *'' Ozarcus''? *'' Stethacanthulus'' *'' Cretacladoides''? – possible Early Cretaceous (Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretace ...) member of the family References {{Taxonbar, from=Q19760083 Carboniferous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmoriiformes
Symmoriiformes is an extinct order of holocephalians. Originally named Symmoriida by Zangerl (1981), it has subsequently been known by several other names. Lund (1986) synonymized the group with Cladodontida, while Maisey (2008) corrected the name to Symmoriiformes in order to prevent it from being mistaken for a family. The symmoriiform fossils record appear at the beginning of the Carboniferous. Most of them died out at the start of the Permian, but ''Dwykaselachus'' is known from the Artinskian-Kungurian of South Africa. Teeth described from the Valanginian of France and Austria indicate that members of the family Falcatidae might have survived until the Early Cretaceous; however, these teeth were also argued to be more likely neoselachian teeth. Fossil distribution Fossil evidence of Symmoriida have been found at Bear Gulch, Fergus County, Montana, Bethel Quarry, Pike County, Indiana, Kinshozan quarry, Alaska, Gifu Prefecture, Japan, Bashkortostan, Russian Federation and pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretacladoides
''Cretacladoides'' ("cladodont likeness from the Cretaceous") is a genus of chondrichthyan, possibly a falcatid, found in France and Austria. Known solely from teeth, mainly found in the Klausrieglerbach locality of Austria, it consists of two species, ''C. ogiveformis'' and ''C. noricum.'' Assuming a falcatid identity, it is the most recent member of the family, which otherwise became extinct at the end of the Carboniferous. History of discovery The teeth of ''Cretacladoides'' were discovered on a field trip by palaeontologist Alexander Lukeneder in 2012. The limestone in which it was found yielded a diverse tooth assemblage, and was dissolved in acetic acid so they could be extracted. In total, 7 kg of limestone contained roughly 88 diagnosable teeth, including 41 teeth that undoubtedly belonged to elasmobranchs. While some of these had been described in a prior paper, the others were mounted on stubs, coated with gold and scanned with an electron microscope at the Palaeont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous Period
The Carboniferous ( ) is a Period (geology), geologic period and System (stratigraphy), system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago (Myr, Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous'' means "coal-bearing", from the Latin ''wikt:carbo#Latin, carbō'' ("coal") and ''wikt:fero#Latin, ferō'' ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern 'system' names, it was coined by geologists William Conybeare (geologist), William Conybeare and William Phillips (geologist), William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Stegocephalia, Tetrapods ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozarcus
''Ozarcus'' is an extinct genus of symmoriiform from the Carboniferous period of Arkansas. The type species, ''Ozarcus mapesae'', was named in 2014 based on cartilaginous skulls from the Serpukhovian-age Fayetteville Formation. The genus is named after the Ozark Mountains (the region of discovery) while the species was named after its discoverer, G. K. Mapes. The holotype fossil, AMNH FF20544 (formerly labelled as OUZC 5300), was a warped yet three-dimensionally-preserved skull with gill baskets. Three additional skulls referrable to ''Ozarcus'' are stored at the AMNH. A partial braincase ( FMNH PF 13242) from the same site, previously been referred to '' Cobelodus'' and described in detail in 2007, was referred to ''Ozarcus'' in 2017. ''Ozarcus'' has branchial arches (bones of the gill basket) with unexpected similarities to osteichthyans (bony fish) rather than chondrichthyans (cartilaginous fish). Like other jawed fish, there are five pairs of branchial arches, not count ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agassizodus
''Agassizodus'' is an extinct genus of eugeneodont holocephalan from the Carboniferous. It belongs to the family Helicoprionidae, which is sometimes called Agassizodontidae. Like other members of its family, it possessed a symphyseal tooth whorl, which was likely present at the tip of the lower jaw and associated with lateral crushing toothplates. The type species, ''A. variabilis'', was originally named ''Lophodus variabilis'' until the name "Lophodus" was determined to be preoccupied. ''A. variabilis'' was originally based on tooth fragments from the Pennsylvanian of Illinois, but the authors who named the genus (St. John and Worthen, 1875) also referred a massive jaw from Osage County, Kansas Osage County (county code OS) is a county located in the U.S. state of Kansas. As of the 2020 census, the county population was 15,766. Its county seat is Lyndon, and its most populous city is Osage City. The county was originally organized i .... The Osage jaw shared some simi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Listracanthus
''Listracanthus'' is a genus of extinct chondrichthyan with uncertain affinities. Species of ''Listracanthus'' are known primarily from their tremendous, feather-like denticles, which range up to four inches in length. The denticles had a large main spine, from which secondary spines emanate from the sides, like the barbs of a feather or a comb. ''Listracanthus'' first appeared in late Carboniferous strata in North America, and eventually disappear from the fossil record some time during the Early Triassic. The appearance of these sharks are largely unknown. However, author and illustrator Ray Troll Ray Troll (born March 4, 1954) is an American artist based in Ketchikan, Alaska. He is best known for his scientifically accurate and often humorous artwork. His most well-known design is "Spawn Till You Die", which has appeared in many places inc ... mentions in his book, ''Sharkabet'', about how paleontologist Rainer Zangerl once discovered a large shale slab containing a lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asphyxia
Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body which arises from abnormal breathing. Asphyxia causes generalized hypoxia, which affects primarily the tissues and organs. There are many circumstances that can induce asphyxia, all of which are characterized by the inability of a person to acquire sufficient oxygen through breathing for an extended period of time. Asphyxia can cause coma or death. In 2015, about 9.8 million cases of unintentional suffocation occurred which resulted in 35,600 deaths. The word asphyxia is from Ancient Greek "without" and , "squeeze" (throb of heart). Causes Situations that can cause asphyxia include but are not limited to: airway obstruction, the constriction or obstruction of airways, such as from asthma, laryngospasm, or simple blockage from the presence of foreign materials; from being in environments where oxygen is not readily accessible: such as underwater, in a low oxygen atmosphere, or in a vacuum; envir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
