Portal:Gastropods/Selected article

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This page is where the articles to be featured on the Gastropods portal are listed.

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A love dart from the land snail Monachoides vicinus
A love dart is a hard, sharp, calcareous or chitinous dart which some hermaphroditic land snails and slugs create. Love darts are made in sexually mature animals only, and are used as part of the sequence of events during courtship before actual mating takes place.

Prior to copulation, each of the two snails (or slugs) attempt to "shoot" one or more darts into the other snail (or slug). There is no organ to receive the dart; this action is more analogous to a stabbing, or to being shot with an arrow. The dart does not fly through the air to reach its target however; instead it is fired as a contact shot.

The love dart is emphatically not a penial stylet (in other words this is not an accessory organ for sperm transfer). The exchange of sperm between each of the two land snails is a completely separate part of the mating progression. Nevertheless, recent research shows that use of the dart can strongly favor the reproductive outcome for the snail that is able to lodge a dart first in its partner. This is because mucus on the dart introduces a hormone-like substance that allows far more of its sperm to survive. (Read more...)

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Geomalacus maculosus, commonly known as the Kerry Slug or Kerry spotted slug, is a species of large air-breathing land slug, a terrestrial pulmonate gastropod mollusc in the family Arionidae, the roundback slugs. An adult slug generally measures about 7–8 cm (2.8–3.2 in) in length, and is a dark greyish colour with yellowish spots.

The distribution of this species includes wild habitats in southwestern Ireland, in north-west Spain and from central to northern Portugal. It favours acidic soil and high humidity environments, and is mostly nocturnal or crepuscular, although is active on overcast days in Ireland. It eats lichens, liverworts, mosses and fungi growing on boulders and on trees. (Read more...)

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The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species of minute freshwater snail with a gill and an operculum, an aquatic gastropod mollusk or micromollusk in the family Hydrobiidae, the mud snails. This tiny snail previously inhabited a small group of thermal springs in the State of New Mexico, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened.

The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico. Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access. (Read more...)

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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...)

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The Chittenango ovate amber snail, scientific name Novisuccinea chittenangoensis, is a species of air-breathing land snail, a terrestrial gastropod mollusk in the family Succineidae, the amber snails. This species is endemic to a very restricted part of the Chittenango area in Madison County, New York, United States. The one extant population is at Chittenango Falls State Park in central New York. It was discovered in 1905.

The only verified extant colony of Novisuccinea chittenangoensis is the type-population at Chittenango Falls, in Chittenango Falls State Park, 3.6 miles north of Cazenovia, between the Towns of Cazenovia and Chittenango, in Madison County, New York. At various times in the past, the species has been thought to have a broader range. To date, although many potentially suitable colony sites have been searched, no colony has been conclusively identified as Novisuccinea chittenangoensis outside of the Chittenango Falls area. The snails survives in and presumably prefer, cool, partially sunlit areas of lush herbaceous growth within the spray zone of the Falls. (Read more...)

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Lobatus gigas (previously known as Strombus gigas), known commonly as the queen conch, is a species of very large edible sea snail, a marine gastropod in the family of true conchs, Strombidae. Lobatus gigas is one of the largest mollusks native to the tropical "Caribbean faunal zone" of the Western Atlantic Ocean, from Bermuda to Brazil. Other common names include pink conch, caracol reina, caracol rosa, caracol rosado, caracol de pala, cobo, botuto, guarura, and lambí.

This large herbivorous gastropod lives in seagrass beds. The adult animal has a very large, solid shell with a characteristic pink-colored aperture and a flared thick outer lip, which is absent in younger specimens. The anatomy of L. gigas is similar to other Strombidae snails, with a long snout, two eyestalks with additional sensory tentacles, a strong foot and a corneous sickle shaped operculum.

Lobatus gigas has a few commensals (such as slipper snails, porcelain crabs and cardinal fishes), parasites (coccidian infections) and predators, including other mollusks, starfish, crustaceans and vertebrates (fish, sea turtles and humans). Its meat is consumed by humans in a wide variety of dishes, and the shell, which is sold as a souvenir and used as a decorative object in contemporary times, was also utilized to fabricate utensils by Native Americans and Caribbean natives in the past. (Read more...)

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Strombus canarium, commonly known as the dog conch, is a species of edible sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs. An Indo-Pacific species, S. canarium lives on mud and sandy bottoms, grazing on algae and detritus. The shell of adult individuals is colored light yellowish-brown to golden to gray. It has a characteristic inflated body whorl, a flared and thick outer lip, and a shallow stromboid notch. Although it is considered to have value as an ornament, because the shell is heavy and compact it is also often used as sinker for fishing nets.

The external anatomy of the soft parts of this species is similar to that of other strombid snails; the animal has an elongate snout, thin eyestalks with well-developed eyes and sensory tentacles, and a narrow, strong foot with a sickle-shaped operculum attached. Among the predators of this snail are carnivorous gastropods such as cone snails and volutes, as well as humans, who consume the soft parts in a wide variety of dishes.

The dog conch is an economically important species in the Indo-West Pacific, and several studies indicate that it may be currently suffering population declines due to overfishing and overexploitation. Malacologists and ecologists have recommended the reduction of the current exploitation rates; recent initiatives in Thailand are attempting to ensure the reproduction of younger individuals, as well as managing the natural populations in general. (Read more...)

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A shell and operculum of Viviparus georgianus

Viviparus georgianus, common name the banded mystery snail, is a species of large freshwater snail with gills and an operculum, an aquatic gastropod mollusk in the family Viviparidae. This snail is native to North America. The specific epithet georgianus is a reference to the southern State of Georgia, where the type locality is situated.

Viviparus georgianus was originally discovered and described (under the name Paludina georgiana) by Isaac Lea in 1834. This snail is found in lakes and slow-moving rivers with mud bottoms. The species thrives in eutrophic lentic environments such as lakes, ponds and some low-flow streams. It is usually absent from larger, faster flowing rivers; however, it is able to survive conditions of high water velocity in the St. Lawrence River, and in the United States it may even be better adapted than the introduced species Bithynia tentaculata to such habitats.

This species is dioecious (it has two distinct sexes), iteroparous (reproducing more than once in a lifetime) and ovoviviparous, laying eggs singly in albumen-filled capsules. (Read more...)

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A live cowry Cypraea chinensis

The Mollusca, common name molluscs or mollusks, is a large phylum of invertebrate animals. There are at least 85,000 recognized extant species of molluscs. This is the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. Molluscs are highly diverse, not only in size and in anatomical structure, but also in behaviour and in habitat.

The phylum Mollusca is typically divided into nine or ten taxonomic classes, of which two are extinct. The gastropods (snails and slugs) include by far the most classified species, accounting for 80% of the total. Molluscs have for many centuries been the source of important luxury goods, notably pearls, mother of pearl, Tyrian purple dye, and sea silk. Their shells have also been used as money in some pre-industrial societies. (Read more...)

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Eobania vermiculata

Eobania vermiculata, also known as Helix vermiculata, common name the "chocolate-band snail" is a species of large, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae, the true snails or typical snails.

This species of large land snail is common in the Mediterranean area, where it is found from eastern Spain to the Crimea. It has been introduced into Australia. It lives in a broad variety of habitats, usually in dry vegetation, mainly in the vicinity of the coast, and also in agricultural crops.

In northern Greece, copulation in this species takes place after the first rainfalls in autumn. These snails create and use love darts as part of their mating behavior. (Read more...)

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Amphibulima browni is a species of small, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Amphibulimidae. This species is endemic to the West Indian island of Dominica. The snail was firstly collected in the late 19th century by biologist A. D. Brown and it was originally described by an American malacologist Henry Augustus Pilsbry in 1899. The type locality is Dominica, the altitude 330 m, "on bananas".

The status of this species was somewhat doubtful for a long period, since the snails were not observed and reported for over 100 years after the original material was collected. However, the collection of a few live specimens during recent surveys in the 2000s finally confirmed that this species is still living in Dominica. Amphibulima browni is likely to meet the IUCN-criteria for listing as Endangered species. (Read more...)

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Many live Hexaplex trunculus in a fish market in Spain

Tyrian purple, also known as royal purple, imperial purple or imperial dye, is a natural purple-red dye which is extracted from certain sea snails, and which was first produced by the ancient Phoenicians. This dye was greatly prized in antiquity because it did not fade, instead it became brighter and more intense with weathering and sunlight. Tyrian purple was expensive: the 4th-century-BC historian Theopompus reported, "Purple for dyes fetched its weight in silver at Colophon" in Asia Minor.

The dye substance is a milky mucous secretion from the hypobranchial gland of one of three species of medium-sized predatory sea snails that occur in the eastern Mediterranean Sea: Bolinus brandaris, the spiny dye-murex; the banded dye-murex Hexaplex trunculus; and the rock-snail Stramonita haemastoma. (Read more...)

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a valve of "Julia borbonica"

Juliidae, common name the bivalved gastropods, is a family of minute sea snails, marine gastropod mollusks or micromollusks in the superfamily Oxynooidea, an opisthobranch group.

This family of snails is extremely unusual in that their shells consist of two separate hinged pieces or valves, which are joined by a ligament, and which look nothing like a normal snail shell, but instead look almost exactly like the two hinged valves of a clam, a bivalve mollusk, a very different class of animals.

In the past the Juliidae were known only from fossil shells, and not surprisingly these fossils were therefore interpreted as being the shells of bivalves. Julia, which is the type genus of the family, was named in 1862 by Augustus Addison Gould, who described it as a bivalve genus. Julliidae are known from the Eocene period to the Recent, but they probably first appeared during the Paleocene. (Read more...)

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Chrysomallon squamiferum, common name the scaly-foot gastropod, is a species of deep-sea hydrothermal-vent snail, a marine gastropod mollusc in the family Peltospiridae. This vent-endemic gastropod is known only from deep-sea hydrothermal vents in the Indian Ocean, where it has been found at depths of about 2,400–2,800 m (1.5–1.7 mi). Chrysomallon squamiferum differs greatly from other deep-sea gastropods, even the closely related neomphalines. The shell is of a unique construction, with three layers; the outer layer consists of iron sulfides, the middle layer is equivalent to the organic periostracum found in other gastropods, and the innermost layer is made of aragonite. The foot is also unusual, being armored with iron-mineralised sclerites. The snail's oesophageal gland houses symbiotic gammaproteobacteria from which the snail appears to obtain its nourishment. This species is considered to be one of the most peculiar deep-sea hydrothermal-vent gastropods, and it is the only known extant animal that incorporates iron sulfide into its skeleton (into both its sclerites and into its shell as an exoskeleton). Its heart is, proportionately speaking, unusually large for any animal: the heart comprises approximately 4% of its body volume. (Read more...)

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