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Caenogastropoda
Caenogastropoda is a taxonomic clade, a large diverse group which are mostly sea snails and other marine gastropod mollusks, but also includes some freshwater snails and some land snails. The clade is the most diverse and ecologically successful of the gastropods. Caenogastropoda contains many families of shelled marine molluscs – including the periwinkles, cowries, wentletraps, moon snails, murexes, cone snails and turrids – and constitutes about 60% of all living gastropods. Biology The Caenogastropoda exhibit torsion, and thus are included in what was previously called the Streptoneura (meaning ''twisted nerves''), also known as Prosobranchia (meaning ''gills forward''). Specifically, they are characterized by having only a single auricle in the heart and a single pair of gill leaflets, and are equivalent to the Monotocardia or Pectinobranchia of older authors. Taxonomy The taxon Caenogastropoda was first established by Leslie Reginald Cox in 1960 as a supero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Snail
Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs to major rivers. The great majority of freshwater gastropods have a shell, with very few exceptions. Some groups of snails that live in freshwater respire using gills, whereas other groups need to reach the surface to breathe air. In addition, some are amphibious and have both gills and a lung (e.g. ''Ampullariidae''). Most feed on algae, but many are detritivores and some are filter feeders. According to a 2008 review of the taxonomy, there are about 4,000 species of freshwater gastropods (3,795–3,972). At least 33–38 independent lineages of gastropods have successfully colonized freshwater environments. It is not possible to quantify the exact number of these lineages yet, because they have yet to be clarified within the Cerit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moon Snails
Naticidae, common name moon snails or necklace shells, is a family of medium to large-sized predatory sea snails, marine gastropod molluscs in the clade Littorinimorpha. The shells of the species in this family are mostly globular in shape. Naticidae is the only family in the superfamily Naticoidea. It has been estimated that worldwide there are about 260–270 recent species of naticid snails. This group is assumed to have originated in the late Triassic or in the early Jurassic. Members of this family can be recognized by the shape of their shells, distinct appearance, or by their predatory behavior. Distribution Naticids are widely distributed and occur worldwide. The greatest diversity of both species and genera is found in tropical regions. Even so, naticid snails are also plentiful in temperate, Arctic and Antarctic waters. Habitat Moon snails live on sandy substrates, at a great variety of depths depending on the species (from the intertidal zone to thousands of meters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Snail
A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as slugs). However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water. Land snails are a polyphyletic group comprising at least ten independent evolutionary transitions to terrestrial life (the last common ancestor of all gastropods was marine). The majority of land snails are pulmonates that have a lung and breathe air. Most of the non-pulmonate land snails belong to lineages in the Caenogastropoda, and tend to have a gill and an operculum. The largest clade of land snails is the Cyclophoroidea, with more than 7,000 species. Many of these operculate land snails live in habitats or microhabitats ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, and land snails and slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian. , 721 families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently extant with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mollusca, and are the most highly diversified class in the phylum, with 65,000 to 80,000 living snail and slug species. The anatomy, behavior, feeding, and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radula
The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs. The arrangement of teeth ( denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other molluscs. Other predatory marine snails ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Snail
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible 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 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'') are sometimes considered to be sea snails and sometimes listed as land snails. Anatomy Sea snails are a very large group of animals and a very diverse one. 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 when they can move around in the air. These air-breathing species includ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penion Jeakingsi
''Penion'' is a genus of large marine snails, commonly known as siphon whelks, classified within the mollusc family Austrosiphonidae, the true whelks.MolluscaBase eds. (2021). MolluscaBase. Penion P. Fischer, 1884. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=488452 on 2021-12-24 Description Siphon whelks are large, benthic marine snails, or whelks. Powell A. W. B., ''New Zealand Mollusca'', William Collins Publishers Ltd, Auckland, New Zealand 1979 Willan, R.C., de C. Cook, S., Spencer, H.G., Creese, R.G., O’Shea, S., Jackson, G.D. Phylum Mollusca. In: de C. Cook, S.C. (eds.), ''New Zealand Coastal Marine Invertebrates 1'', 406 – 407. Canterbury University Press, Christchurch, New Zealand ''Penion'' are commonly called siphon whelks because they have a very long siphon. Species typically have a large, pointed operculum. Ponder, W.F. 1973. A review of the Australian species of ''Penion'' Fischer (Neogastropo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesogastropoda
Mesogastropoda was for many years a traditional taxonomic group of snails, an order. The order was composed mostly of sea snails, but it also included some land snails and freshwater snails, all of which were prosobranch gastropod mollusks. This order was introduced by J. Thiele in his work from 1921, it and was used for many decades subsequently. Recent research in malacology however has made it clear that ''Mesogastropoda'' was not a monophyletic taxon, and because of that, the taxon is no longer included in modern classifications. Nonetheless most of the standard texts and field guides on mollusks date from the time period when this classification was still current, and therefore references to mesogastropods or Mesogastropoda are frequently encountered. The lower taxa that were traditionally contained in Mesogastropoda are now mostly placed in the superorder Caenogastropoda. A more detailed account of the taxonomy is given in the articles on Gastropoda and Archaeogastropod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cowries
Cowrie or cowry () is the common name for a group of small to large sea snails, marine gastropod mollusks in the family Cypraeidae, the cowries. The term ''porcelain'' derives from the old Italian term for the cowrie shell (''porcellana'') due to their similar appearance. Shells of certain species have historically been used as currency in several parts of the world, as well as being used, in the past and present, very extensively in jewelry, and for other decorative and ceremonial purposes. The cowrie was the shell most widely used worldwide as shell money. It is most abundant in the Indian Ocean, and was collected in the Maldive Islands, in Sri Lanka, along the Indian Malabar coast, in Borneo and on other East Indian islands, in Maluku in the Pacific, and in various parts of the African coast from Ras Hafun to Mozambique. Cowrie shell money was important in the trade networks of Africa, South Asia, and East Asia. In the United States and Mexico, cowrie species inhabit the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leslie Reginald Cox
Leslie Reginald Cox FRS (22 November 1897, Islington – 5 August 1965) was an English palaeontologist and malacologist. Education Cox was born to parents who worked as government servants, in the Post Office telephone engineers' department. When he was still young, the family moved to Harringay, where he at age six started attendance at the South Harringay County School. In 1909, he entered Owen's School in Islington, one of the old London grammar schools. Awards and honours Cox was elected a Fellow of the Royal Society in 1950. His nomination reads: He was elected president of the Geologists' Association The Geologists' Association, founded in 1858, is a British organisation with charitable status for those concerned with the study of geology. It publishes the ''Proceedings of the Geologists' Association'' and jointly with the Geological Society ... for 1954–56. Career In August 1916, Cox began his war service. Publications Cox's most important publications include: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest. In humans, other mammals, and birds, the heart is divided into four chambers: upper left and right atria and lower left and right ventricles. Commonly the right atrium and ventricle are referred together as the right heart and their left counterparts as the left heart. Fish, in contrast, have two chambers, an atrium and a ventricle, while most reptiles have three chambers. In a healthy heart blood flows one way through the heart due to heart valves, which prevent backflow. The heart is enclosed in a protective sac, the pericardium, which also contains a small amount of fluid. The wall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxon
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's Linnaean taxonomy, system in ''Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard de Jussieu, Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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