Portal:Gastropods
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. , 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 articleByne'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
David Dwight Baldwin (1831–1912) was a businessman, educator, and biologist on Maui in the Hawaiian Islands. Within biology he is known for his contributions to the study of Hawaiian land snails, the terrestrial pulmonate gastropod mollusks of the Hawaiian Islands.
Baldwin was born on November 26, 1831 in Honolulu. His father was early missionary doctor Dwight Baldwin (1798–1886), and his mother was Charlotte Fowler Baldwin (1805–1873). After a few years living in Waimea, the family moved to the island of Maui in about 1837. Baldwin lived in Connecticut for a time and received both his undergraduate degree and a Master of Arts from Yale. In 1890, he moved to Haʻikū, where his younger brother Henry Perrine Baldwin (1842–1911) had founded the agricultural venture Alexander & Baldwin with his brother-in-law Samuel Thomas Alexander (1836–1904). At this time Baldwin devoted much of his efforts to studying mollusks, i.e. to malacology, specifically the study of Hawaiian land snails, some of which he named and described. In addition, several land snail species in the family Achatinellidae were named in honor of him, as well as a subgenus Baldwinia of the genus Partulina. He produced the first catalog of Hawaiian land snails and freshwater snails in 1893. (Read more...) Did you know?
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Selected imageAn apertural view of a shell of the small, air-breathing, freshwater snail Physella acuta in the family Physidae. This an example of a sinistral or left-handed shell, which means that if the shell is held with the aperture facing the observer, and the spire pointing up, then the aperture is on the left-hand side. In this genus the aperture is long and large, and the spire is pointed. The shell is thin and corneous, and rather transparent. The family Physidae and the family Planorbidae are within the superfamily Planorboidea; all the species within these families have shells that are left-handed. In general however, sinistral shell coiling is quite rare among the gastropods. 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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