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Valvata Piscinalis
''Valvata piscinalis'', common name the European stream valvata or European valve snail, is a species of small freshwater snail with gills and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails. It is also known as ''Cincinna piscinalis'' (Müller, 1774). Subspecies Subspecies of ''Valvata piscinalis'' include:Glöer, P. 2002 ''Die Süßwassergastropoden Nord- und Mitteleuropas''. Die Tierwelt Deutschlands, ConchBooks, Hackenheim, 326 pp., , page 190-194. * ''Valvata piscinalis piscinalis'' (O. F. Müller, 1774) * '' Valvata piscinalis antiqua'' (Morris, 1838) * '' Valvata piscinalis geyeri'' (Menzel, 1904) - The name ''geyeri'' is in honor of German zoologist David Geyer (1855–1932). * '' Valvata piscinalis discors'' (Westerlund, 1886) * '' Valvata piscinalis alpestris'' (Küster, 1853) Shell description ''Valvata piscinalis'' has a somewhat pinched aperture and an attenuate spire.Grigorovich, I. A., E. L. Mills, C. B. Richards, D. Br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Friedrich Müller
Otto Friedrich Müller, also known as Otto Friedrich Mueller (2 November 1730 – 26 December 1784) was a Denmark, Danish natural history, naturalist and scientific illustrator. Biography Müller was born in Copenhagen. He was educated for the church, became tutor to a young nobleman, and after several years' travel with him, settled in Copenhagen in 1767, and married a lady of wealth. His first important works, ''Fauna Insectorum Friedrichsdaliana'' (Leipzig, 1764), and ''Flora Friedrichsdaliana'' (Strasbourg, 1767), giving accounts of the insects and flora of the estate of Frederiksdal House, Frederiksdal, near Copenhagen, recommended him to Frederick V of Denmark, by whom he was employed to continue the ''Flora Danica'' a comprehensive atlas of the flora of Denmark. Müller added two volumes to the three published by Georg Christian Oeder since 1761. The study of invertebrates began to occupy his attention almost exclusively, and in 1771 he produced a work in German on “Cer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutrophic
Eutrophication is a general term describing a process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water; ie. the process of too many plants growing on the surface of a river, lake, etc., often because chemicals that are used to help crops grow have been carried there by rain. Eutrophication may occur naturally or as a result of human actions. Manmade, or cultural, eutrophication occurs when sewage, industrial wastewater, fertilizer runoff, and other nutrient sources are released into the environment. Such nutrient pollution usually causes algal blooms and bacterial growth, resulting in the depletion of dissolved oxygen in water and causing substantial environmental degradation. Many policies have been introduced to combat eutrophication, including the United Nations Development Program (UNDP)'s sustainability development goals. Approaches for prevention and reversal of eutrophication include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caucasus
The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, including the Greater Caucasus range, have conventionally been considered as a natural barrier between Europe and Asia, bisecting the Eurasian landmass. Mount Elbrus, Europe's highest mountain, is situated in the Western Caucasus area of Russia. On the southern side, the Lesser Caucasus includes the Javakheti Plateau and the Armenian highlands. The Caucasus is divided into the North Caucasus and South Caucasus, although the Western Caucasus also exists as a distinct geographic space within the North Caucasus. The Greater Caucasus mountain range in the north is mostly shared by Russia and Georgia as well as the northernmost parts of Azerbaijan. The Lesser Caucasus mountain range in the south is mostly located on the territory of sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibet
Tibet (; ''Böd''; ), or Greater Tibet, is a region in the western part of East Asia, covering much of the Tibetan Plateau and spanning about . It is the homeland of the Tibetan people. Also resident on the plateau are other ethnic groups such as Mongols, Monpa people, Monpa, Tamang people, Tamang, Qiang people, Qiang, Sherpa people, Sherpa, Lhoba people, Lhoba, and since the 20th century Han Chinese and Hui people, Hui. Tibet is the highest region on Earth, with an average elevation of . Located in the Himalayas, the highest elevation in Tibet is Mount Everest, Earth's highest mountain, rising above sea level. The Tibetan Empire emerged in the 7th century. At its height in the 9th century, the Tibetan Empire extended far beyond the Tibetan Plateau, from the Tarim Basin and Pamirs in the west, to Yunnan and Bengal in the southeast. It then divided into a variety of territories. The bulk of western and central Tibet (Ü-Tsang) was often at least nominally unified under a ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia Minor
Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean Sea to the west, the Turkish Straits to the northwest, and the Black Sea to the north. The eastern and southeastern limits have been expanded either to the entirety of Asiatic Turkey or to an imprecise line from the Black Sea to the Gulf of Alexandretta. Topographically, the Sea of Marmara connects the Black Sea with the Aegean Sea through the Bosporus and the Dardanelles, and separates Anatolia from Thrace in Southeast Europe. During the Neolithic, Anatolia was an early centre for the development of farming after it originated in the adjacent Fertile Crescent. Beginning around 9,000 years ago, there was a major migration of Anatolian Neolithic Farmers into Neolithic Europe, Europe, with their descendants coming to dominate the continent a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palearctic
The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. The realm consists of several bioregions: the Mediterranean Basin; North Africa; North Arabia; Western, Central and East Asia. The Palaearctic realm also has numerous rivers and lakes, forming several freshwater ecoregions. Both the eastern and westernmost extremes of the Paleartic span into the Western Hemisphere, including Cape Dezhnyov in Chukotka Autonomous Okrug to the east and Iceland to the west. The term was first used in the 19th century, and is still in use as the basis for zoogeographic classification. History In an 1858 paper for the ''Proceedings of the Linnean Society'', British zoologist Philip Sclater first identified six terrestrial zoogeographic realms of the world: Palaearctic, Aethiopian/ Afrotropic, Indian/ I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenidium (mollusc)
A ctenidium is a respiratory organ or gill which is found in many molluscs. This structure exists in bivalves, cephalopods, polyplacophorans (chitons), and in aquatic gastropods such as freshwater snails and marine snails. Certain molluscs, such as the bivalves, possess paired ctenidia, but others, such as members of the Ampullariidae, bear a single ctenidium. A ctenidium is shaped like a comb or a feather, with a central part from which many filaments or plate-like structures protrude, lined up in a row. Some aquatic gastropods possess a single row of filaments on their ctenidium, known as the monopectinate condition, and others have a pair of filament rows, known as the bipectinate or aspidobranch condition. The ctenidium hangs into the mantle cavity and increases the area available for gas exchange. The apple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snout
A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, Rostrum (anatomy), rostrum, beak or proboscis. The wet furless surface around the nostrils of the nose of many mammals is called the rhinarium (colloquially this is the "cold wet snout" of some mammals). The rhinarium is often associated with a stronger sense of olfaction. Variation Snouts are found on many mammals in a variety of shapes. Some animals, including ursines and great cats, have box-like snouts, while others, like shrews, have pointed snouts. Pig snouts are flat and cylindrical. Primates Strepsirrhine primates have muzzles, as do baboons. Great apes have reduced muzzles, with the exception being human beings, whose face does not have protruding jaws nor a snout but merely a human nose. Dogs The muzzle begins at the Stop (dog), stop, just below the eyes, and includes the dog's nose and mouth. In the domestic dog, most of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilicus (mollusc)
The umbilicus of a coiled mollusc shell is the axially aligned, hollow cone-shaped space within its whorl (mollusc), whorls. The term ''umbilicus'' is often used in descriptions of gastropoda, gastropod shells, i.e. it is a feature present on the ventral (or under) side of many (but not all) snail shells, including some species of sea snails, land snails, and freshwater snails. The word is also applied to the depressed central area on the planispiral coiled shells of ''Nautilus'' species and fossil ammonites. (These are not gastropods, but shelled cephalopods.) In gastropods The spirally coiled whorls of gastropod shells frequently connect to each other by their inner sides, during the natural course of its formation. This results in a more or less solid central axial pillar, known as the columella (mollusc), columella. The more intimate the contact between the concave side of the whorls is, the more solid the columella becomes. On the other hand, if this connection is less inten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, Huron, Lake Erie, Erie, and Lake Ontario, Ontario (though hydrologically, Lake Michigan–Huron, Michigan and Huron are a single body of water, joined at the Straits of Mackinac). The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The lakes connect to the Atlantic Ocean via the Saint Lawrence River, and to the Mississippi River basin through the Illinois Waterway. The Great Lakes are the largest group of freshwater lakes on Earth by total area and the second-largest by total volume. They contain 21% of the world's surface fresh water by volume. The total surface is , and the total volume (measured at the low water datum) is , slightly less than the volume of Lake Baikal (, 22–23% of the world's surface f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valvata Sincera
''Valvata sincera'', common name the mossy valvata is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusc in the family Valvatidae ''Valvatidae'', the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks. Taxonomy The family Valvatidae has no subfamilies (according to the taxonomy of the Gastropoda by Bouche ..., the valve snails. References * Turgeon, D.D., et al. 1998. ''Common and scientific names of aquatic invertebrates of the United States and Canada''. American Fisheries Society Special Publication 26 Further readingBoreal Turret Snail, ''Valvata sincera'' Natural Heritage & Endangered Species Program. 2 pp. Valvatidae Gastropods described in 1824 {{Valvatidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
