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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] |
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] |
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] |
Multicuspid
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a wisdom tooth. It is the last tooth to appear, breaking through the front of the gum at about the age of 20, although this varies from individual to individual. Race can also affect the age at which this occurs, with statistical variations between groups. In some cases, it may not even erupt at all. The human mouth contains upper (maxillary) and lower (mandibul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonites
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) than they are to shelled nautiloids such as the living ''Nautilus'' species. The earliest ammonites appeared during the Devonian, with the last species vanishing during the Cretaceous–Paleogene extinction event. Ammonites are excellent index fossils, and linking the rock layer in which a particular species or genus is found to specific geologic time periods is often possible. Their fossil shells usually take the form of planispirals, although some helically spiraled and nonspiraled forms (known as heteromorphs) have been found. The name "ammonite", from which the scientific term is derived, was inspired by the spiral shape of their fossilized shells, which somewhat resemble tightly coiled rams' horns. Pliny the Elder ( 79 AD near Pomp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galeomorphii
Galeomorphii is a superorder of cartilaginous fishes which includes all modern sharks except the dogfish and its relatives. They are sometimes called galea or galean sharks. There are about 300 living species in 23 families. Galean sharks are divided into four orders: the Heterodontiformes, Orectolobiformes, Lamniformes, and Carcharhiniformes Classification Order Heterodontiformes The bullhead sharks are a small order of basal modern sharks (Neoselachii). All are relatively small, with the largest species being just in adult length. They are bottom feeders in tropical and subtropical waters. They appear in the fossil record in the Early Jurassic, well before any of the other galean sharks. However, they have never been common, and it is likely their origin lies even further back. There are nine living species in a single genus, ''Heterodontus'' and a single family. * Family Heterodontidae (Bullhead sharks) Order Orectolobiformes Carpet sharks are another small or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenacanthiformes
Ctenacanthiformes is an extinct order of chondrichthyan fish. They possessed ornamented fin spines and cladodont dentition. Members of the family Ctenacanthidae may have survived into the Cretaceous based on teeth found in deep water deposits of 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 Cretaceou ... age in France and Austria. References Prehistoric cartilaginous fish orders {{Paleo-cartilaginous-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpet Shark
Carpet sharks are sharks classified in the order Orectolobiformes . Sometimes the common name "carpet shark" (named so because many species resemble ornately patterned carpets) is used interchangeably with "wobbegong", which is the common name of sharks in the family Orectolobidae. Carpet sharks have five gill slits, two spineless dorsal fins, and a small mouth that does not extend past the eyes. Many species have barbels. Characteristics The carpet sharks are a diverse group of sharks with differing sizes, appearances, diets, and habits. They first appeared in the fossil record in the Early Jurassic; the oldest known orectolobiform genera are '' Folipistrix'' (known from Toarcian to Aalenian of Belgium and Germany), '' Palaeobrachaelurus'' (Aalenian to Barremian) and '' Annea'' (Toarcian to Bajocian of Europe). All species have two dorsal fins and a relatively short, transverse mouth that does not extend behind the eyes. Besides the nostrils are barbels, tactile sensory organs, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcharhiniformes
Carcharhiniformes , the ground sharks, are the largest order of sharks, with over 270 species. They include a number of common types, such as catsharks, swellsharks, and the sandbar shark. Members of this order are characterized by the presence of a nictitating membrane over the eye, two dorsal fins, an anal fin, and five gill slits. The families in the order Carcharhiniformes are expected to be revised; recent DNA studies show that some of the conventional groups are not monophyletic. The oldest members of the order appeared during the Middle-Late Jurassic, which have teeth and bodyforms that are morphologically similar to living catsharks. Carchariniformes first underwent major diversification during the Late Cretaceous, initially as small-sized forms, before radiating into medium and large body sizes during the Cenozoic. Families According to FishBase, the nine families of ground sharks are: [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altusmirus
''Altusmirus'' is an extinct genus of ground shark from the Early Cretaceous age of Austria. There is only one known species, ''A. triquetrus'', named by Iris Fuchs in 2018. It was related to ''Fornicatus''. References {{Taxonbar, from=Q49001026 Carcharhiniformes Prehistoric shark genera Fossil taxa described in 2018 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
