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Lepeta Depressa
''Nacella concinna'' is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Nacellidae, one of the families of true limpets.Bouchet, P. (2014). Nacella polaris (Hombron & Jacquinot, 1841). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=713922 on 2015-01-26 Description The shell of ''Nacella concinna'' grows to about long with deep water specimens being rather smaller. It is an elongated ovate, moderately elevated cone with a low apex somewhat towards the anterior margin and angled in that direction. There are about 30 faint radial ribs and a series of fine concentric lines that indicate the annual growth rings. The exterior of the shell is varying shades of pale brown and grey and the interior is dark purplish-brown in deep water specimens but creamy-brown in those from shallow water. The mantle has a fringe of short tentacles. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Orkneys
The South Orkney Islands are a group of islands in the Southern Ocean, about north-east of the tip of the Antarctic Peninsula''Antarctica: Secrets of the Southern Continent'' p. 122 , David McGonigal, 2009 and south-west of . They have a total area of about . The islands are claimed both by Britain (as part of the British Antarctic Territory since 1962, previously as a Falkland Islands Dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petermann Island
Petermann Island () is an island long, lying southwest of Hovgaard Island in the Wilhelm Archipelago, Antarctica. Location Petermann Island is off the Graham Coast of the Antarctic Peninsula. It is in the Wilhelm Archipelago, southwest of Hovgaard Island and Booth Island, east of the Vedel Islands and northeast of the French Passage. It is northwest of Mount Shackleton on the mainland. The island is long and across. It rises steeply to elevations of up to from a rocky coastline with raised pebble beaches. It has volcanic origins, with about half the land surface covered by a permanent, crevassed icecap. Ice-free areas have a sparse vegetation of mosses and lichens. The bedrock of the island is granodiorite. Important Bird Area The island has been identified as an Important Bird Area (IBA) by BirdLife International because it supports a breeding colony of about 3,000 pairs of gentoo penguins. Other birds nesting at the site in smaller numbers include Adélie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anvers Island
Anvers Island or Antwerp Island or Antwerpen Island or Isla Amberes is a high, mountainous island long, the largest in the Palmer Archipelago of Antarctica. It was discovered by John Biscoe in 1832 and named in 1898 by the Belgian Antarctic Expedition under Adrien de Gerlache after the province of Antwerp (province), Antwerp in Belgium. It lies Ordinal directions, south-west of Brabant Island at the Ordinal directions, south-western end of the group. The south-western coastline of the island forms part of the Southwest Anvers Island and Palmer Basin Antarctic Specially Managed Area (ASMA 7). Cormorant Island, an Important Bird Area, lies 1 km off the south coast. There is a small science outpost called Palmer Station on the south end of Anvers island since the late 1960s; it is the smallest and farthest north of three the U.S. has on the continent. It is staffed by a few dozen people mostly doing marine and biology research, and is usually resupplied by ship as it has no reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wandel Island
Booth Island (or Wandel Island; ) is a Y-shaped island, long and rising to in the northeast part of the Wilhelm Archipelago, Antarctica. Location Booth Island is off the east end of the Graham Coast on the west side of the Antarctic Peninsula. It is in the Wilhelm Archipelago, to the northeast of the Vedel Islands and southwest of the Wauwermans Islands. It is separated from the mainland by the Lemaire Channel, to the southeast. It is east of Cape Renard at the entrance to Flandres Bay. Booth Island is partly covered by an ice cap of varying thickness. The ice is at most about thick. Sailing directions The US Defense Mapping Agency's ''Sailing Directions for Antarctica'' (1976) describes Booth Island as follows: Discovery and name Booth Island was discovered and named by a German expedition under Eduard Dallmann in 1873-74, probably for Oskar Booth or Stanley Booth, or both, members of the Hamburg Geographical Society at that time. The United States Advisory Committee on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paulet Island
Paulet Island is a Circle, circular island about in diameter, lying south-east of Dundee Island, off the north-eastern end of the Antarctic Peninsula. Because of its large penguin colony, it is a popular destination for sightseeing tours. Description The island is composed of lava flows capped by a cinder cone with a small summit crater. Geothermal energy, Geothermal heat keeps parts of the island ice-free, and the youthful morphology of the volcano suggests that it was last active within the last 1,000 years. The island is part of the James Ross Island Volcanic Group. Historic monuments Paulet Island was discovered by a British expedition (1839–1843) under James Clark Ross and named by him for Captain (Royal Navy), Captain The Right Honourable, the Right Honorable Lord George Paulet (Royal Navy officer), George Paulet, Royal Navy. In 1903 during the Swedish Antarctic Expedition led by Otto Nordenskiöld his ship ''Antarctic (ship), Antarctic'' was crushed and sunk by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seymour Island
Seymour Island or Marambio Island, is an island in the chain of 16 major islands around the tip of the Graham Land on the Antarctic Peninsula. Graham Land is the closest part of Antarctica to South America. It lies within the section of the island chain that resides off the west side of the peninsula's northernmost tip. Within that section, it is separated from Snow Hill Island by Picnic Passage, and sits just east of the larger key, James Ross Island, and its smaller, neighboring island, Vega Island. Seymour Island is sometimes called Marambio Island or Seymour-Marambio Island, taking its resident Argentine base as its namesake (see section, #Base Antárctica Marambio, Base Antárctica Marambio, below). Sailing directions The US Defense Mapping Agency's ''Sailing Directions for Antarctica'' (1976) describes Seymour Island as follows: Historic site A wooden commemorative plaque, plaque and rock cairn stand at Penguins Bay, on the southern coast of Seymour Island. The pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bouvet Island
Bouvet Island ( ; ) is an uninhabited subantarctic volcanic island and dependency of Norway. It is a protected nature reserve, and situated in the South Atlantic Ocean at the southern end of the Mid-Atlantic Ridge, it is the world's most extreme points of Earth#Remoteness, remote island. Located north of the Antarctic Circle, Bouvet Island is not part of the southern region covered by the Antarctic Treaty System. The island lies north of the Princess Astrid Coast of Queen Maud Land, Antarctica, east of the South Sandwich Islands, south of Gough Island, and south-southwest of the coast of South Africa. It has an area of , 93 percent of which is covered by a glacier. The centre of the island is the ice-filled crater of an inactive volcano. Some Skerry, skerries and one smaller island, Larsøya, lie along its coast. Nyrøysa, created by a rock slide in the late 1950s, is the only easy place to land and is the location of a weather station. The island was first spotted on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Shetlands
The South Shetland Islands are a group of Antarctic islands located in the Drake Passage with a total area of . They lie about north of the Antarctic Peninsula, and between southwest of the nearest point of the South Orkney Islands. By the Antarctic Treaty of 1959, the islands' sovereignty is neither recognized nor disputed by the signatories. According to British government language on the topic, "the whole of Antarctica is protected in the interests of peace and science." The islands have been claimed by three countries, beginning with the United Kingdom since 1908 (since 1962 as part of the equally unrecognized British Antarctic Territory). The islands are also claimed by the governments of Chile (since 1940, as part of the Antártica Chilena province), and by Argentina (since 1943, as part of Argentine Antarctica, Tierra del Fuego Province). Several countries maintain research stations on the islands. Most of them are situated on King George Island, benefitting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Georgia Island
South Georgia is an island in the Atlantic Ocean, South Atlantic Ocean that is part of the British Overseas Territories, British Overseas Territory of South Georgia and the South Sandwich Islands. It lies around east of the Falkland Islands. Stretching in the east–west direction, South Georgia is around long and has a maximum width of . The terrain is mountainous, with the central ridge rising to at Mount Paget. The northern coast is indented with numerous bays and fjords, serving as harbor, harbours. Discovered by Europeans in 1675, South Georgia had no indigenous population due to its harsh climate and remoteness. Captain James Cook in made the first landing, survey and mapping of the island. On 17 January 1775, Cook claimed it a British possession, naming it "Isle of Georgia" after George III, King George III. Through its history of South Georgia and the South Sandwich Islands, history, it served as a whaling and seal hunting base, with intermittent population scattere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Snail
Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible Gastropod shell, shell. Definition Determining whether some gastropods should be called sea snails is not always easy. Some species that live in brackish water (such as certain Neritidae, neritids) can be listed as either freshwater snails or marine snails, and some species that live at or just above the high tide level (for example, species in the genus ''Truncatella (gastropod), Truncatella'') are sometimes considered to be sea snails and sometimes listed as land snails. Anatomy Sea snails are a very large and diverse group of animals. Most snails that live in salt water respire using a gill or gills; a few species, though, have a lung, are intertidal, and are active only at low tide w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Peninsula
The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martin in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. The Antarctic Peninsula is part of the larger peninsula of West Antarctica, protruding from a line between Cape Adams (Weddell Sea) and a point on the mainland south of the Eklund Islands. Beneath the ice sheet that covers it, the Antarctic Peninsula consists of a string of bedrock islands; these are separated by deep channels whose bottoms lie at depths considerably below current sea level. They are joined by a grounded ice sheet. Tierra del Fuego, the southernmost tip of South America, is about away across the Drake Passage. The Antarctic Peninsula is in area and 80% ice-covered. The marine ecosystem around the western continental shelf of the Antarctic Peninsula (WAP) has been subjected to rapid Climate change in Antarctica, clima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
