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Pristiophorus Nudipinnis
The shortnose sawshark, (''Pristiophorus nudipinnis'') or southern sawshark, is a sawshark of the family Pristiophoridae. The body of this shark is slightly compressed, and its rostrum is narrow. The two dorsal fins are almost identical in size. In color, the dorsal side of this sawshark tends to be uniformly slate gray, with few or no markings. The ventral side is pale white or cream. Females reach around long, and males reach around long. These sharks can live up to 9 years. Behavior Leading a benthic lifestyle, the shortnose sawshark primarily feeds on benthic invertebrates and small bony fish. Like other sawsharks, this species' reproduction is ovoviviparous. It gives birth biannually to a litter of 7-14 pups. The size of pups at birth is about . Conservation Because of stable commercial catch rates, reduced Total Allowable Catch, protection in Victorian waters, and a high rate of biological productivity, the shortnose sawshark is listed as Least Concern by the IUCN Red L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Günther
Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther (3 October 1830 – 1 February 1914), was a German-born British zoologist, ichthyologist, and herpetologist. Günther is ranked the second-most productive reptile taxonomist (after George Albert Boulenger) with more than 340 reptile species described. Early life and career Günther was born in Esslingen in Swabia (Württemberg). His father was a ''Stiftungs-Commissar'' in Esslingen and his mother was Eleonora Nagel. He initially schooled at the Stuttgart Gymnasium. His family wished him to train for the ministry of the Lutheran Church for which he moved to the University of Tübingen. A brother shifted from theology to medicine, and he, too, turned to science and medicine at Tübingen in 1852. His first work was "''Ueber den Puppenzustand eines Distoma''". He graduated in medicine with an M.D. from Tübingen in 1858, the same year in which he published a handbook of zoology for students of ... [...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 (anatomy), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "the depths." Organisms living in this zone are called benthos and include microorganisms (e.g., bacteria and fungi) as well as larger invertebrates, such as crustaceans and polychaetes. Organisms here generally live in close relationship with the substrate and many are permanently attached to the bottom. The benthic boundary layer, which includes the bottom layer of water and the uppermost layer of sediment directly influenced by the overlying water, is an integral part of the benthic zone, as it greatly influences the biological activity that takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud. Description Oceans The benthic region of the ocean begins at the shore line (intertidal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovoviviparous
Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop inside eggs that remain in the mother's body until they are ready to hatch. The young of some ovoviviparous amphibians, such as ''Limnonectes larvaepartus'', are born as larvae, and undergo further metamorphosis outside the body of the mother. Members of genera ''Nectophrynoides'' and ''Eleutherodactylus'' bear froglets, not only the hatching, but all the most conspicuous metamorphosis, being completed inside the body of the mother before birth. Among insects that depend on opportunistic exploitation of transient food sources, such as many Sarcophagidae and other carrion flies, and species such as many Calliphoridae, that rely on fresh dung, and parasitoids such as tachinid flies that depend on entering the host as soon as possible, the emb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least Concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biological species. It uses a set of precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. With its strong scientific base, the IUCN Red List is recognized as the most authoritative guide to the status of biological diversity. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit. The aim of the IUCN Red List is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to reduce species extinction. According to IUCN the formally stated goals of the Red List are to provi ... [...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 and b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Described In 1870
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 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
