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Langental Formation
The Langental Formation, also spelled as Langetal Formation, is a Late Eocene (Bartonian to Priabonian) geologic formation cropping out in the Sperrgebiet, ǁKaras Region of southwestern Namibia. The siltstones and sandstones of the formation were deposited in a shallow marine environment. The Langental Formation was deposited under hot and humid conditions. The formation overlies the Silica Beds unit and is overlain by the Blaubok Conglomerate.Dauteuil et al., 2018, p.6 The Langental Formation provides many fossil invertebrates and fish. Fossil content Among others, the following fossils are reported from the formation: at .org ;Fish * '' [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcharodon Hastalis
''Cosmopolitodus'' is an extinct genus of mackerel shark that lived between thirty to one million years ago during the late Oligocene to the Early Pleistocene epochs. Its type species is ''Cosmopolitodus hastalis'', the broad-tooth mako (other common names include the extinct giant mako and broad-tooth white shark). In 2021, ''Isurus planus'' was reassigned to the genus, and thus became the second species '' C. planus''. Its teeth can reach lengths up to 3.5 in (7.5 cm) and are found worldwide. It is believed to be an ancestor to the great white shark, an argument supported by the transitional species ''Carcharodon hubbelli'', but as of 2021, no phylogenetic analyses have been done for proof. Taxonomy Etymology ''Cosmopolitodus'' is derived from the Ancient Greek κοσμοπολίτης "''kosmopolítēs''" meaning "citizen of the world" and ὀδών "''odṓn''" meaning "tooth". The specific name ''hastalis'' may be derived from the Latin word ''hasta'' meaning "spear". ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontaspis Contortidens
''Odontaspis'' (from el, ὀδούς 'tooth') and el, ἀσπίς 'shield') is a genus of sand shark with two extant species. Description Bigeye sand tigers can reach a length of about and smalltooth sand tigers of about 4.1 m. They are large-bodied sharks with long, conical snouts, broad-based dorsal and anal fins, and an asymmetrical caudal fin with a strong lower lobe. Their teeth are large, with prominent narrow cusps. They are distinguished from the similar genus ''Carcharias'' by the absence of crushing posterior teeth.Bourdon, J''Odontaspis'' Agassiz 1838 ''Elasmo.com''. Retrieved on December 24, 2008. These bottom dwelling, deepwater sharks can be found in temperate and tropical waters of all the oceans. Extant species * ''Odontaspis ferox'' ( A. Risso, 1810) (smalltooth sand tiger) * ''Odontaspis noronhai'' (Maul, 1955) (bigeye sand tiger) Extinct species Extinct species within this genus include: * ''Odontaspis aculeatus'' Capetta & Case, 1975 * ''Odon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myliobatis Dixoni
''Myliobatis'' is a genus of eagle rays in the family Myliobatidae. Description ''Myliobatis'' species can reach a width up to about . Their bodies consist of a rhomboidal disc, wider than long, with one dorsal fin. The head is broad and short, with eyes and spiracles on the sides. The tail is slender, with one or two large spines at the base, without tail fin. The teeth are arranged in the lower and upper jaws in flat tooth plates called pavement teeth, each consisting of about seven series of plates, which are used to crush clam shells and crustaceans. Biology ''Myliobatis'' species are ovoviviparous. Their gestation last about 6 months and a female produces four to seven embryos. ''Myliobatis'' species mainly feed on molluscs, bottom-living crustaceans, and small fishes. Habitat ''Mylobatis'' species live in warm, shallow waters. Adults prefer sandy shores, while juveniles can usually be encountered offshore. Species Extant species Currently, 11 species in this genus a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamna Vincenti
''Lamna'' is a genus of mackerel sharks in the family Lamnidae, containing two extant species: the porbeagle (''L. nasus'') of the North Atlantic and Southern Hemisphere, and the salmon shark (''L. ditropis'') of the North Pacific. Endothermy The two species of this genus can keep their blood temperature higher above that of the water surrounding them than other cartilaginous fish, with temperature differences recorded up to 15.6 °C. '' |
Isurus Desorii
''Isurus'' is a genus of mackerel sharks in the family Lamnidae, commonly known as the mako sharks. Description The two living species are the common shortfin mako shark (''I. oxyrinchus'') and the rare longfin mako shark (''I. paucus''). They range in length from , and have an approximate maximum weight of . They both have a distinctive blue-gray color scheme common among mackerel sharks. Several extinct species are known from fossils found in sediments from the Cretaceous to the Quaternary (age range: 99.7 to 0.781 million years ago). The family Lamnidae also includes the great white shark and the porbeagle. Mako sharks are capable of swimming at speeds up to . The great white shark is also closely related to an ancient mako shark species, ''Isurus hastalis''. However, fossil evidence suggests ''I. hastalis'', like the great white shark, also belonged to the genus '' Carcharodon''. Species The genus contains these species: * ''Isurus oxyrinchus'' ( Rafinesque, 1810) (short ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galeus Robustus
''Galeus'' is a genus of catshark, belonging to the family Scyliorhinidae, commonly known as sawtail catsharks in reference to a distinctive saw-toothed crest of enlarged dermal denticles, found along the upper edges of their caudal fins. They are found in the Atlantic, the western and central Pacific, and the Gulf of California, inhabiting deep waters at or close to the sea floor. Members of this genus are rather small, slim sharks with firm bodies and thick, rough skin. Their heads are usually fairly long and pointed, and have large mouths with well-developed furrows at the corners. They have large pectoral and anal fins, and two similar dorsal fins placed well back. Many species are ornately patterned with dark saddles and/or blotches. Sawtail catsharks feed on various invertebrates and fishes, and may be either egg-laying or live-bearing. These harmless sharks are sometimes caught as bycatch but are of minimal commercial value. Taxonomy ''Galeus'', derived from the Greek ''g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galeocerdo Latidens
''Galeocerdo'' is a genus of requiem sharks that have lived since the Paleocene epoch. While these sharks were formerly diverse, only ''G. cuvier'' (the modern tiger shark) survives today. Species Species in the genus ''Galeocerdo'' include: * †''Galeocerdo aduncus'' * †''Galeocerdo alabamensis'' * †''Galeocerdo clarkensis'' * ''Galeocerdo cuvier'' * †'' Galeocerdo denticulatus'' * †'' Galeocerdo eaglesomi'' * †''Galeocerdo gibberulus'' * †'' Galeocerdo latidens'' * †''Galeocerdo mayumbensis'' * †''Galeocerdo minor'' * †''Galeocerdo mixtus'' * †''Galeocerdo productus ''Galeocerdo'' is a genus of requiem sharks that have lived since the Paleocene epoch. While these sharks were formerly diverse, only ''G. cuvier'' (the modern tiger shark) survives today. Species Species in the genus ''Galeocerdo'' include: ...'' References {{Taxonbar, from=Q2186811 Shark genera Taxa named by Johannes Peter Müller Taxa named by Friedrich Gustav Jakob Henl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
