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Ascandra Contorta
''Ascandra contorta'' is a species of calcareous sponge belonging to the family Clathrinidae. This is a whitish sponge which appears as a mass of irregular, convoluted tubes. It is very similar to '' Clathrina clathrus'' but usually differs in colour (''C. clathrus'' is usually yellow) and by the presence of terminal oscula on vertical tubes (absent in ''C. clathrus''). When viewed microscopically, the spicule structure of the two species is very different, ''A. contorta'' possessing two-pointed ''diactines'' and four-pointed ''tetractines'' as well as the three-pointed ''triactines'' which ''C. clathrus'' is exclusively made up of. This sponge is found on north-eastern Atlantic coasts from the Arctic to the Mediterranean, usually on rocks at depths of 10–30 m, but occasionally in shallower water. References''Clathrina contorta'' at Marine Species Identification Portal contorta ''Pinus contorta'', with the common names lodgepole pine and shore pine, and also known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Scott Bowerbank
James Scott Bowerbank (14 July 1797 – 8 March 1877) was a British naturalist and palaeontologist. Biography Bowerbank was born in Bishopsgate, London, and succeeded in conjunction with his brother to his father's distillery, in which he was actively engaged until 1847. In early years astronomy and natural history, especially botany, engaged much of his attention; he became an enthusiastic worker at the microscope, studying the structure of shells, corals, moss agates, and flints. He also formed an extensive collection of fossils. The organic remains of the London Clay attracted particular attention, and about the year 1836 he and six other workers founded The London Clay Club – the members comprising Dr Bowerbank, Frederick E. Edwards (1799–1875), author of ''The Eocene Mollusca'' ( Palaeontograph. Soc.), Searles Valentine Wood, John Morris, Alfred White (zoologist), N. T. Wetherell, surgeon of Highgate (1800–1875), and James De Carle Sowerby. In 1840, Bowerbank pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. 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. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists 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. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous Sponge
The calcareous sponges of class Calcarea are members of the animal phylum Porifera, the cellular sponges. They are characterized by spicules made of calcium carbonate in the form of calcite or aragonite. While the spicules in most species have three points, in some species they have either two or four points. Biology All sponges in this class are strictly marine, and, while they are distributed worldwide, most are found in shallow tropical waters. Like nearly all other sponges, they are sedentary filter feeders. All three sponge body plans are represented within class Calcarea : asconoid, syconoid, and leuconoid. Typically, calcareous sponges are small, measuring less than in height, and drab in colour. However, a few brightly coloured species are also known. Calcareous sponges vary from radially symmetrical vase-shaped body types to colonies made up of a meshwork of thin tubes, or irregular massive forms. The skeleton has either a mesh or honeycomb structure. Classifica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clathrinidae
Clathrinidae is a family of calcareous sponges in the order Clathrinida. It contains the following genera: ''Arturia'' '' Borojevia'' '' Brattegardia'' ''Clathrina'' ''Ernstia ''Ernstia'' is a genus of calcareous sponges in the family Clathrinidae. The genus was erected in 2013 to contain five species previously assigned to ''Clathrina''. The genus name honors German naturalist Ernst Haeckel for his contributions towar ...'' '' Nicola'' References {{calcarea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clathrina Clathrus
''Clathrina clathrus'' is a species of calcareous sponge belonging to the family Clathrinidae. This yellow (occasionally white) sponge, up to 10 cm in diameter, usually appears cushion-shaped at a distance (its close relative '' Clathrina coriacea'' is normally flatter in appearance). Close-up the sponge can be seen to consist of a tangled mass of tubes (these tubes are thicker and less tightly knit than in ''C. coriacea'' and there is no osculum as found in that species). Like ''C. coriacea'', the spicules are exclusively three-pointed ''triactines''. This is a shallow-water species found in the Mediterranean and on Atlantic coasts of Europe as far north as the British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, .... References''Clathrina clathrus'' at Marine Speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osculum
The osculum (plural "oscula") is an excretory structure in the living sponge, a large opening to the outside through which the current of water exits after passing through the spongocoel. Wastes diffuse into the water and the water is pumped through the osculum carrying away with it the sponge's wastes. Sponges pump large volumes of water: typically a volume of water equal to the sponge's body size is pumped every five seconds. The size of the osculum is regulated by contractile myocytes. Its size, in turn, is one of the factors which determines the amount of water flowing through the sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t .... It can be closed completely in response to excess silt in the water. References Sponge anatomy {{animal-anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sponge Spicule
Spicules are structural elements found in most sponges. The meshing of many spicules serves as the sponge's skeleton and thus it provides structural support and potentially defense against predators. Sponge spicules are made of calcium carbonate or silica. Large spicules visible to the naked eye are referred to as megascleres, while smaller, microscopic ones are termed microscleres. The composition, size, and shape of spicules are major characters in sponge systematics and taxonomy. Overview Sponges are a species-rich clade of the earliest-diverging (most basal) animals. They are distributed globally, with diverse ecologies and functions, and a record spanning at least the entire Phanerozoic. Most sponges produce skeletons formed by spicules, structural elements that develop in a wide variety of sizes and three dimensional shapes. Among the four sub-clades of Porifera, three (Demospongiae, Hexactinellida, and Homoscleromorpha) produce skeletons of amorphous silica and on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic
The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, Norway, Russia (Murmansk Oblast, Murmansk, Siberia, Nenets Autonomous Okrug, Nenets Okrug, Novaya Zemlya), Sweden and the United States (Alaska). Land within the Arctic region has seasonally varying snow and sea ice, ice cover, with predominantly treeless permafrost (permanently frozen underground ice) containing tundra. Arctic seas contain seasonal sea ice in many places. The Arctic region is a unique area among Earth's ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted to its cold and extreme conditions. Life in the Arctic includes zooplankton and phytoplankton, fish and marine mammals, birds, land animals, plants and human societies. Arctic land is bordered by the subarctic. De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediterranean
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the east by the Levant. The Sea has played a central role in the history of Western civilization. Geological evidence indicates that around 5.9 million years ago, the Mediterranean was cut off from the Atlantic and was partly or completely desiccated over a period of some 600,000 years during the Messinian salinity crisis before being refilled by the Zanclean flood about 5.3 million years ago. The Mediterranean Sea covers an area of about , representing 0.7% of the global ocean surface, but its connection to the Atlantic via the Strait of Gibraltar—the narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates the Iberian Peninsula in Europe from Morocco in Africa—is only wide. The Mediterranean Sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascandra
''Ascandra'' is a genus of calcareous sponges of the family Leucaltidae and are found in oceans around the world. Species As of 2019, 15 valid species of ''Ascandra'' are recognized: * '' Ascandra ascandroides'' (Borojevic, 1971) * '' Ascandra atlantica'' (Thacker, 1908) * '' Ascandra biscayae'' (Borojevic & Boury-Esnault, 1987) * '' Ascandra brandtae'' (Rapp, Göcke, Tendal & Janussen, 2013) * '' Ascandra contorta'' (Bowerbank, 1866) * '' Ascandra corallicola'' (Rapp, 2006) * '' Ascandra crewsi'' Van Soest & De Voogd, 2015 * ''Ascandra densa ''Ascandra densa'' is a species of calcareous sponge The calcareous sponges of class Calcarea are members of the animal phylum Porifera, the cellular sponges. They are characterized by spicules made of calcium carbonate in the form of calc ...'' Haeckel, 1872 * '' Ascandra falcata'' Haeckel, 1872 * '' Ascandra izuensis'' (Tanita, 1942) * '' Ascandra kakaban'' Van Soest & De Voogd, 2015 * '' Ascandra loculosa'' (Dendy, 1891) * '' Asc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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