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Ikamauius
''Ikamauius'' is an extinct genus of sawshark from the Cenozoic of New Zealand. It contains a single species, ''I. ensifer''. It is most closely related to the extant ''Pliotrema The sixgill sawshark, ''Pliotrema warreni'' is a sawshark of the family Pristiophoridae. Presence of 6 pairs of gill slits highlights this genus among sharks; outside Hexanchiformes order, ''Pliotrema'' is the only shark with more than 5 gill s ...'', but is distinguished by the presence of barbs on both sides of its rostral denticles. References Fish of New Zealand Pristiophoridae Prehistoric cartilaginous fish genera {{Shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sawshark
A sawshark or saw shark is a member of a shark order (Pristiophoriformes ) bearing a unique long, saw-like rostrum (snout or bill) edged with sharp teeth, which they use to slash and disable their prey. There are eight species within the Pristiophoriformes, including the longnose or common sawshark (''Pristiophorus cirratus''), shortnose sawshark (''Pristiophorus nudipinnis''), Japanese sawshark (''Pristiophorus japonicas''), Bahamas sawshark (''Pristiophorus schroederi''), sixgill sawshark (''Pliotrema warreni''), African dwarf sawshark (''Pristiophorus nancyae''), Lana's sawshark (''Pristiophorus lanae'') and the tropical sawshark (''Pristiophorus delicatus''). Sawsharks are found in many areas around the world, most commonly in waters from the Indian Ocean to the southern Pacific Ocean. They are normally found at depths around 40–100 m, but can be found much lower in tropical regions. The Bahamas sawshark was discovered in deeper waters (640 m to 915 m) of the northwest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek grc, label=none, πλεῖστος, pleīstos, most and grc, label=none, καινός, kainós (latinized as ), 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by the Isthmus of Panama, causing a faunal interchange between the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James William Davis
James William Davis (1846, Leeds-1893) was a British naturalist who specialised in fossil fish. He lived at Chevinedge, Halifax in Yorkshire. James William Davis was a leading member of the Yorkshire Naturalists' Union and a Fellow of the Geological Society of London. Works partial list *Davis, J.W. (1879) Description of a new species of fossil fish spine, ''Ctenacanthus minor'', from the Lower Coal-Measures of Yorkshire. ''Geological Magazine'', decade 2, 6: 531–532 *Davis, J.W. (1880) On the fish fauna of the Yorkshire Coal Field. ''Proceedings of the Geologists' Association'', 6 (8): 359–370 *Davis, J. W. (1880) On a new species of ''Gyracanthus'', a fossil fish from the Coal-Measures. A''nnals and Magazine of Natural History'' 6:372-373Online here*Davis, J.W. (1880) On the genus ''Pleuracanthus'', Agass., including ''Orthacanthus'', Agass., and Gold., ''Diplodus'', Agass., and ''Xenacanthus'', Beyr. ''Quarterly Journal of the Geological Society of London'', 36: 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dasyatis
''Dasyatis'' (Greek δασύς ''dasýs'' meaning rough or dense and βατίς ''batís'' meaning skate) is a genus of stingray in the family Dasyatidae that is native to the Atlantic, including the Mediterranean. In a 2016 taxonomic revision, many of the species formerly assigned to ''Dasyatis'' were reassigned to other genera ('' Bathytoshia'', '' Fontitrygon'', '' Hemitrygon'', '' Hypanus'', '' Megatrygon'' and '' Telatrygon''). Species *'' Dasyatis dipterura'' ( D. S. Jordan & C. H. Gilbert, 1880) (diamond stingray) *''Dasyatis chrysonota'' A. Smith, 1828 (blue stingray) *'' Dasyatis hypostigma'' H. R. S. Santos & M. R. de Carvalho, 2004 (groovebelly stingray) *'' Dasyatis marmorata'' Steindachner, 1892 (marbled stingray) *'' Dasyatis pastinaca'' Linnaeus, 1758 (common stingray) *'' Dasyatis tortonesei'' Capapé, 1975 (Tortonese's stingray) Fossil species *† ''Dasyatis africana'' Arambourg, 1947 See also * List of prehistoric cartilaginous fish This list of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pristiophorus
''Pristiophorus'' is a genus of sawsharks found in the Pacific, Atlantic and Indian oceans. Members of this genus differ from the Sixgill Sawshark ''(Pliotrema warreni)'' in having five gill slits. Their rostral sawteeth lack prominent transverse ridges on the basal ledges, and the large teeth are not posteriorly serrated. Species There are currently seven recognized species in this genus: * '' Pristiophorus cirratus'' ( Latham, 1794) (Longnose sawshark) * '' Pristiophorus delicatus'' Yearsley, Last & W. T. White, 2008 (Tropical sawshark) * '' Pristiophorus japonicus'' Günther, 1870 (Japanese sawshark) * '' Pristiophorus lanae'' Ebert & Wilms, 2013 (Lana's sawshark)Ebert, D.A. & Wilms, H.A. (2013)''Pristiophorus lanae'' sp. nov., a new sawshark species from the Western North Pacific, with comments on the genus ''Pristiophorus'' Müller & Henle, 1837 (Chondrichthyes: Pristiophoridae).Pp. 86-100 in: de Carvalho, M.R., Ebert, D.A., Ho, H.-C. & White, W.T. (eds.) : Systematics an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configuration of continents. It is the latest of three geological eras since complex life evolved, preceded by the Mesozoic and Paleozoic. It started with the Cretaceous–Paleogene extinction event, when many species, including the non-avian dinosaurs, became extinct in an event attributed by most experts to the impact of a large asteroid or other celestial body, the Chicxulub impactor. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammalsthe eutherians (placentals) in the northern hemisphere and the metatherians (marsupials, now mainly restricted to Australia) in the southern hemisphere. The extinction of many groups allowed mammals and birds to greatly diversify so tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the List of island countries, sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's Capital of New Zealand, capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliotrema
The sixgill sawshark, ''Pliotrema warreni'' is a sawshark of the family Pristiophoridae. Presence of 6 pairs of gill slits highlights this genus among sharks; outside Hexanchiformes order, ''Pliotrema'' is the only shark with more than 5 gill slits. Unlike other sawsharks, the barbs on this shark's rostrum continue onto the sides of the head. Its barbels are also closer to its mouth than in other species. At maximum, females can reach over 136 cm long, and males can reach over 112 cm long. Range and habitat The sixgill sawshark is found in the temperate and subtropical waters of the western Indian Ocean between latitudes 23° S and 37° S, at depths of between 37 and 500 m. This shark lives in the benthic and benthopelagic zones of the continental shelf. Adults are partially segregated from juveniles, as they naturally tend to aggregate at lower depths. Behavior Using their sensitive barbels and electric sense, sixgill sawsharks are able to find their p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of New Zealand
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
