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Distomus Variolosus
''Distomus variolosus'' is a species of tunicate or sea squirt in the family Styelidae. It is native to the northeastern Atlantic Ocean where it lives on the seabed,Gittenberger, A.; Sanamyan, K. (2015)''Distomus variolosus'' Gaertner, 1774.In: Shenkar, N.; Gittenberger, A.; Lambert, G.; Rius, M.; Moreira Da Rocha, R.; Swalla, B.J.; Turon, X. (2015) Ascidiacea World Database. Accessed through: World Register of Marine Species on 2015-12-23 typically on the stems and fronds of kelp. Description ''Distomus variolosus'' is a colonial sea squirt that forms leathery patches, often encircling the stems of kelp. The zooids are globose or ovoid and about high, with the two short siphons close together near the apex. It is difficult to distinguish the buccal siphon from the exhalant siphon. The zooids are separate, but linked by the base or the sides. Zooids with closed siphons have a warty appearance, giving the species its specific name. Generally red, the colonies may be spotted with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Gaertner
Joseph Gaertner (12 March 1732 – 14 July 1791) was a German botanist, best known for his work on seeds, ''De Fructibus et Seminibus Plantarum'' (1788-1792). Biography He was born in Calw, and studied in Göttingen under Albrecht von Haller. He was primarily a naturalist, but also worked at physics and zoology. He travelled extensively to visit other naturalists. He was professor of anatomy in Tübingen in 1760, and was appointed professor of botany at St Petersburg in 1768, but returned to Calw in 1770. Gaertner made back cross to convert one species into another. Back cross increases nuclear gene frequency His observations were: 1. Dominance of traits 2. Equal contribution of male and female to the progeny 3. No variation in F1 (first generation of descendants) 4. Large variation in F2 (second generation of descendants) including parental and intermediate types 5. Some of F2 plants had entirely new traits but he was unable to give possible explanation for observ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Atlantic Ocean
Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Greek equivalent of fauna. ''Fauna'' is also the word for a book that catalogues the animals in such a manner. The term was first used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stolidobranchia
Stolidobranchia is an order of tunicates in the class Ascidiacea.Lambert, G.; Gittenberger, A.; Sanamyan, K. (2015)Stolidobranchia.In: Shenkar, N.; Gittenberger, A.; Lambert, G.; Rius, M.; Moreira Da Rocha, R.; Swalla, B.J.; Turon, X. (2015) Ascidiacea World Database. Accessed through: World Register of Marine Species on 2015-12-23 The group includes both colonial and solitary animals. They are distinguished from other tunicates by the presence of folded pharyngeal baskets. This provides the etymology of their name: in ancient Greek, means the "fold" of a cloth. Stolidobranchian sea squirts are also characterized by the complete absence of an abdomen. The abdominal organs of other tunicates are instead located to one side of the pharyngeal basket in this group. Taxonomy *Molgulidae Lacaze-Duthiers 1877 exacrobylidae Seeliger 1906; Caesiridae**''Anomopera'' Hartmeyer, 1923 **''Asajirus'' Kott, 1989 'Hexadactylus'' Monniot & Monniot 1990**''Bostrichobranchus'' Traustedt, 1883 * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be itself a substrate for an animal that lives on top of the algae. Inert substrates are used as growing support materials in the hydroponic cultivation of plants. In biology substrates are often activated by the nanoscopic process of substrate presentation. In agriculture and horticulture * Cellulose substrate * Expanded clay aggregate (LECA) * Rock wool * Potting soil * Soil In animal biotechnology Requirements for animal cell and tissue culture Requirements for animal cell and tissue culture are the same as described for plant cell, tissue and organ culture (In Vitro Culture Techniques: The Biotechnological Principles). Desirable requirements are (i) air conditioning of a room, (ii) hot room with temperature recorder, (iii) microscope r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Column
A water column is a conceptual column of water from the surface of a sea, river or lake to the bottom sediment.Munson, B.H., Axler, R., Hagley C., Host G., Merrick G., Richards C. (2004).Glossary. ''Water on the Web''. University of Minnesota-Duluth. Retrieved 27 May 2014. Descriptively, the deep sea water column is divided into five parts—'' pelagic zones'' (from Greek πέλαγος (pélagos), 'open sea')—from the surface to below the floor, as follows: ''epipelagic'', from the surface to 200 meters below the surface; ''mesopelagic'', from 200 to 1000 meters below the surface; '' bathypelagic'', from 1000 to 4000 meters below the surface; ''abyssopelagic'', from 4000 meters below the surface to the level sea floor; ''hadopelagic'', depressions and crevices below the level sea floor. The concept of water column is useful since many aquatic phenomena are explained by the incomplete vertical mixing of waters with discrete chemical, physical or biological characteristics. Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicata, tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called Gonochorism, gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maja Brachydactyla
''Maja brachydactyla'' is a species of crab in the family Majidae. It was initially described as a subspecies of '' M. squinado.'' A review of the species complex published in 1998 was able to differentiate between specimens from the Mediterranean Sea and those from the Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ..., and concluded that the Atlantic specimens were a separate species, accepted as ''M. brachydactyla'' Balss, 1922. References {{Taxonbar, from=Q1885533 Majoidea Crustaceans described in 1922 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Majoidea
The Majoidea are a Superfamily (taxonomy), superfamily of crabs which includes the various spider crabs. Taxonomy In "''A classification of living and fossil genera of decapod crustaceans''" De Grave and colleagues divided Majoidea into six families: * Family Epialtidae ** Subfamily Epialtinae ** Subfamily Pisinae ** Subfamily Pliosomatinae ** Subfamily Tychiinae * Family Hymenosomatidae * Family Inachidae * Family Inachoididae * Family Majidae ** Subfamily Eurynolambrinae ** Subfamily Majinae ** Subfamily Micromaiinae ** Subfamily Mithracinae ** Subfamily Planoterginae * Family Oregoniidae The classification has since been revised, with subfamilies Epialtinae and Mithracinae being elevated to families and Hymenosomatidae being moved to its own superfamily. The family composition according to the World Register of Marine Species is as follows: * family Epialtidae MacLeay, 1838 * family Inachidae MacLeay, 1838 * family Inachoididae Dana, 1851 * family Macrocheiridae Dana, 1851 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroid (zoology)
Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish. Some hydroids such as the freshwater '' Hydra'' are solitary, with the polyp attached directly to the substrate. When these produce buds, they become detached and grow on as new individuals. The majority of hydroids are colonial. The original polyp is anchored to a solid substrate and forms a bud which remains attached to its parent. This in turn buds and in this way a stem is formed. The arrangement of polyps and the branching of the stem is characteristic of the species. Some species have the polyps budding directly off the stolon which roots the colony. The polyps are connected by epidermis which surrounds a gastrovascular cavity. The epidermis secretes a chitinous skeleton which supports the stem and in some hydroids, the skeleton extends into a cup shape surrounding the polyp. Most of the polyps are gastrozooids or feeding polyps, but some are specialised reprodu ... [...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] |
