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 calcite or aragonite. While the spicules in most species hav ... from Australia. The species name is derived from a Latin term meaning "dense" or "compact". References World Register of Marine Species entry densa Sponges described in 1872 Sponges of Australia {{calcarea-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |
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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]   |
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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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Sponges Described In 1872
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 them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Sponges were first to branch off the evolutionary tree from the last common ancestor of all animals, making them the sister group of all other animals. Etymology The term ''sponge'' derives from the Ancient Greek word ( 'sponge'). Overview Sponges are similar to other animals in that they are multicellular, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |