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Procerodes Littoralis
''Procerodes littoralis'' is a species of triclad flatworm widely distributed on the shores of northwestern Europe and on the east coast of North America from Newfoundland northwards. Description ''Procerodes littoralis'' is a small flatworm with a maximum length of and width of , but it is usually smaller than this. It has a fairly wide head with two distinctive marginal tentacles with a pair of eyes behind them. The neck region is slightly narrower and the body is plump and bottle-shaped. The dorsal surface is greyish or olive-brown and the internal organs are sometimes visible through the cuticle. The eyes are surrounded by pale patches which are separated by a slightly darker stripe. Distribution and habitat ''Procerodes littoralis'' is found in the temperate northwestern Atlantic Ocean, on the European coastline, and on the coast of North America from Newfoundland northwards. It is common round the coasts of Britain on the upper and middle shores where it is the most common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Strøm
Hans Strøm (25 January 1726 – 1 February 1797) was a Norwegian clergyman. He also became a prominent zoologist and naturalist. He is best associated with his topographical description of the traditional district of Sunnmøre. Life Hans Strøm was born at Borgund in Møre og Romsdal, Norway. His father was a clergyman and many other relatives of both his father and mother were ministers. He attended the Bergen Cathedral School. He was educated as a Lutheran clergyman and in 1745 took a theological degree at the University of Copenhagen. Then he worked from 1750 to 1764 as chaplain in Borgund. In 1764 he became parish priest, first in Volda where he served until 1779, when he went to Eiker where he served as Vicar for 18 years. He died at Hokksund in Øvre Eiker in Buskerud. Topography Strøm is particularly known as a topographer, and especially for the model physical and economic description he gave of Søndmør's bailiff's office (1762–69), also called Søndmør ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricladida
A planarian is one of the many flatworms of the traditional class Turbellaria. It usually describes free-living flatworms of the order Tricladida (triclads), although this common name is also used for a wide number of free-living platyhelminthes. Planaria are common to many parts of the world, living in both saltwater and freshwater ponds and rivers. Some species are terrestrial and are found under logs, in or on the soil, and on plants in humid areas. The triclads are characterized by triply branched intestine and anteriorly situated ovaries, next to the brain. Today the order Tricladida is split into three suborders, according to their phylogenetic relationships: Maricola, Cavernicola and Continenticola. Formerly, the Tricladida was split according to habitats: Maricola, which is marine; Paludicola which inhabits freshwater; and Terricola, which is land-dwelling. Planaria exhibit an extraordinary ability to regenerate lost body parts. For example, a planarian split lengt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flatworm
The flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. Unlike other bilaterians, they are acoelomates (having no body cavity), and have no specialized circulatory and respiratory organ (anatomy), organs, which restricts them to having flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion. The digestive cavity has only one opening for both ingestion (intake of nutrients) and egestion (removal of undigested wastes); as a result, the food cannot be processed continuously. In traditional medicinal texts, Platyhelminthes are divided into Turbellaria, which are mostly non-parasitic animals such as planarians, and three entirely parasitic groups: Cestoda, Trematoda and Monogenea; however, since the turbellarians have since been prove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligochaeta
Oligochaeta () is a subclass of animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadrile earthworms (some of which are semiaquatic or fully aquatic), and freshwater or semiterrestrial microdrile forms, including the tubificids, pot worms and ice worms ( Enchytraeidae), blackworms ( Lumbriculidae) and several interstitial marine worms. With around 10,000 known species, the Oligochaeta make up about half of the phylum Annelida. These worms usually have few setae (chaetae) or "bristles" on their outer body surfaces, and lack parapodia, unlike polychaeta. Diversity Oligochaetes are well-segmented worms and most have a spacious body cavity (coelom) used as a hydroskeleton. They range in length from less than up to in the 'giant' species such as the giant Gippsland earthworm (''Megascolides australis'') and the Mekong worm (''Amynth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopoda
Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, and five pairs of branching appendages on the abdomen that are used in respiration. Females brood their young in a pouch under their thorax. Isopods have various feeding methods: some eat dead or decaying plant and animal matter, others are grazers, or filter feeders, a few are predators, and some are internal or external parasites, mostly of fish. Aquatic species mostly live on the seabed or bottom of freshwater bodies of water, but some taxa can swim for a short distance. Terrestrial forms move around by crawling and tend to be found in cool, moist places. Some species are able to roll themselves into a ball as a defense mechanism or to conserve moisture. There are over 10,000 identified species of isopod worldwide, with around 4,50 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jaera Albifrons
''Jaera albifrons'' is a species of isopod in the family Janiridae Janiridae is a family of isopods in the order Isopoda. There are more than 20 genera and 190 described species in Janiridae. Genera These 25 genera belong to the family Janiridae: * '' Austrofilius'' Hodgson, 1910 * '' Caecianiropsis'' Menzies .... It is found in Europe and North America. References External links * Asellota Crustaceans of the Atlantic Ocean Taxa named by William Elford Leach Crustaceans described in 1814 Articles created by Qbugbot {{isopod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jaera Nordmanni
''Jaera'' is a genus of isopods in the family Janiridae. There are more than 20 described species in ''Jaera''. Species These 22 species belong to the genus ''Jaera'': * ''Jaera albifrons'' Leach, 1814 * '' Jaera bocqueti'' Veuille & Kocatas, 1979 * '' Jaera caspica'' Kesselyak, 1938 * '' Jaera danubica'' Brtek, 2003 * '' Jaera forsmani'' Bocquet, 1950 * '' Jaera hopeana'' Costa, 1853 * '' Jaera ischiosetosa'' Forsman, 1949 * '' Jaera istri'' Veuille, 1979 * '' Jaera italica'' Kesselyak, 1938 * '' Jaera maculosa'' Leach, 1814 * ''Jaera marina'' * ''Jaera nordica'' Lemercier, 1958 * '' Jaera nordmanni'' (Rathke, 1837) * '' Jaera petiti'' Schulz, 1953 * '' Jaera posthirsuta'' Forsman, 1949 * ''Jaera praehirsuta'' Forsman, 1949 * ''Jaera sarsi'' Valkanov, 1936 * ''Jaera schellenbergi'' Kesselyak, 1938 * ''Jaera sorrentina'' Verhoeff, 1943 * ''Jaera syei ''Jaera'' is a genus of isopods in the family Janiridae. There are more than 20 described species in ''Jaera''. Species These ... [...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] |
Direct Development
Marine larval ecology is the study of the factors influencing dispersing larvae, which many marine invertebrates and fishes have. Marine animals with a larva typically release many larvae into the water column, where the larvae develop before metamorphosing into adults. Marine larvae can disperse over long distances, although determining the actual distance is challenging, because of their size and the lack of a good tracking method. Knowing dispersal distances is important for managing fisheries, effectively designing marine reserves, and controlling invasive species. Theories on the evolution of a biphasic life history Larval dispersal is one of the most important topics in marine ecology, today. Many marine invertebrates and many fishes have a bi-phasic life cycle with a pelagic larva or pelagic eggs that can be transported over long distances, and a demersal or benthic adult. There are several theories behind why these organisms have evolved this biphasic life history: *Larva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maricola
Maricola is a suborder of triclad flatworms including species that mainly inhabit salt water environments. However, some species are also known from freshwater or brackish waters.Ball, I. R. 1974. La Faune Terrestre de l'Ile de Saint Hélène: Turbellaria Tricladida. Ann. Mus. Roy. Afr. Centrale, in 8. Zool. Taxonomy and phylogeny History The Maricola group was first proposed by Hallez in 1892. He recognized three families: Otoplanida, Procerodida and Bdellourida. Two years later, in 1884, Hallez renamed these families as Otoplanidae, Procerodidae and Bdellouridae. In 1906 Böhmig classified the Maricola in two families and five subfamilies: Procerodidae (Euprocerodinae, Cercyrinae, Micropharynginae) and Bdellouridae (Uteriporinae, Eubdellourinae). In 1909 Wilhelmi wrote a monograph on the group in which five families were described: Procerodidae, Uteriporidae, Cercyridae, Bdellouridae, Micropharyngidae. Von Graff used the same classification in 1916. In 1989 Sluys recognize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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