The gastropods portalGastropods (/ˈɡæstrəpɒdz/), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (/ɡæsˈtrɒpədə/). This class comprises snails and slugs from saltwater, freshwater, and from the land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, land snails and slugs. The class Gastropoda is a diverse and highly successful class of mollusks within the phylum Mollusca. It 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. As of 2017[update], 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 reproductive adaptations of gastropods vary significantly from one clade or group to another, so stating many generalities for all gastropods is difficult. The class Gastropoda has an extraordinary diversification of habitats. Representatives live in gardens, woodland, deserts, and on mountains; in small ditches, great rivers, and lakes; in estuaries, mudflats, the rocky intertidal, the sandy subtidal, the abyssal depths of the oceans, including the hydrothermal vents, and numerous other ecological niches, including parasitic ones. Although the name "snail" can be, and often is, applied to all the members of this class, commonly this word means only those species with an external shell big enough that the soft parts can withdraw completely into it. Slugs are gastropods that have no shell or a very small, internal shell; semislugs are gastropods that have a shell that they can partially retreat into but not entirely. The marine shelled species of gastropods include species such as abalone, conches, periwinkles, whelks, and numerous other sea snails that produce seashells that are coiled in the adult stage—though in some, the coiling may not be very visible, for example in cowries. In a number of families of species, such as all the various limpets, the shell is coiled only in the larval stage, and is a simple conical structure after that. (Full article...) Selected article Byne's disease, more accurately known as Bynesian decay, is a peculiar and permanently damaging condition (resulting from an on-going chemical reaction) which often attacks mollusk shells that are in storage or on display for long periods of time. Bynesian decay is a form of efflorescence of salts formed by the reaction of acidic vapors with the basic shell surface. This can superficially resemble a growth of mold. Although this condition was first described in the early 19th century, Bynesian decay was not well understood until almost a hundred years later. The condition is named after the man (Loftus Byne) who is best known for describing it in the late 19th century, even though he was not the first person to describe this condition in a publication. In addition, Byne mistakenly assumed that the condition was caused by bacteria, and thus the condition came to be referred to as a "disease". As well as mollusk shells, various other natural history specimens are susceptible to this form of decay, including eggshells and some fossils and mineral samples that are composed of calcium carbonate. This condition is of concern for museum scientists, and also for anyone who has a private collection of specimens of these kinds. (Read more...) Selected biography  Ernst Heinrich Philipp August Haeckel (February 16, 1834 – August 9, 1919), also written von Haeckel, was an eminent German biologist, naturalist, philosopher, physician, professor and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many terms in biology, including anthropogeny, ecology, phylum, phylogeny, and the kingdom Protista. Haeckel promoted and popularized Charles Darwin's work in Germany and developed the controversial recapitulation theory ("ontogeny recapitulates phylogeny"), claiming that an individual organism's biological development, or ontogeny, parallels and summarizes its species' entire evolutionary development, or phylogeny. Haeckel coined many now ubiquitous terms including "anthropogeny", "phylum", "phylogeny", "ecology". He proposed the kingdom Protista in 1866. His chief interests lay in evolution and life development processes in general, including development of nonrandom form, which culminated in his beautifully illustrated book Kunstformen der Natur (Art forms of nature), which includes over 100 detailed, multi-colour illustrations of animals and sea creatures, including the shells of a variety of marine gastropods. (Read more...) Did you know?
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Selected image An apertural view of an adult shell of the extremely large sea snail known as the Australian trumpet, Syrinx aruanus in the family Turbinellidae. This species is the largest Recent shelled gastropod species; the height of the shell can be up to 91 cm. The shell itself is usually pale apricot in color as shown here, however in life the shell is covered by thick brown or grey periostracum. The whole shell has a spindle-like shape and the spire of the shell is quite high. The whorls usually have a strong keel and the shell has a long siphonal canal. There are no folds on the columella, unlike some other genera within the same family. In this image, a rod is visible protruding from the siphonal canal; this metal structure is used to support the specimen as it is on display in the Houston Museum of Natural Science. Lists of gastropods
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Related portalsSubcategoriesCategories about gastropods: Request to editors: please do not create any more categories of gastropods by country. Instead create list articles, article with a list of the marine or non-marine gastropods of whichever country or area you are interested in. We would also like to empty and delete the two remaining country categories we have, adding that information to list articles instead. Thank you. Things to do
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