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Alcadia Guadaloupensis
''Alcadia guadaloupensis'' is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae. Description (Original description in Latin) The shell is flattened and somewhat angular, showing fine concentric striations. The columella is nodulous at the base. The outer lip is thick and reflexed. The whorls gradually increase in size, and are somewhat swollen above and below. The operculum is brown and horny. Distribution This species occurs in Guadeloupe Guadeloupe (; ; gcf, label=Antillean Creole, Gwadloup, ) is an archipelago and overseas department and region of France in the Caribbean. It consists of six inhabited islands—Basse-Terre, Grande-Terre, Marie-Galante, La Désirade, and the .... References * {{taxonbar, from=Q107038562 guadaloupensis Gastropods described in 1842 Endemic fauna of Guadeloupe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...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] |
Terrestrial Animal
Terrestrial animals are animals that live predominantly or entirely on land (e.g. cats, dogs, ants, spiders), as compared with aquatic animals, which live predominantly or entirely in the water (e.g. fish, lobsters, octopuses), and amphibians, which rely on a combination of aquatic and terrestrial habitats (e.g. frogs and newts). Some groups of insects are terrestrial, such as ants, butterflies, earwigs, cockroaches, grasshoppers and many others, while other groups are partially aquatic, such as mosquitoes and dragonflies, which pass their larval stages in water. Terrestrial animals tend to be more developed and intelligent than aquatic animals. Terrestrial classes The term "terrestrial" is typically applied to species that live primarily on the ground, in contrast to arboreal species, which live primarily in trees. There are other less common terms that apply to specific groups of terrestrial animals: *Saxicolous creatures are rock dwelling. "Saxicolous" is derived from t ... [...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] |
Mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat. The phylum is typically divided into 7 or 8 taxonomic classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurologically advanced of all invertebrates—and either the giant squid or the colossal squid is the largest known invertebrate species. The gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicinidae
Helicinidae is a family of small tropical land snails which have an operculum. They are terrestrial operculate gastropod mollusks in the superfamily Helicinoidea. These snails are not at all closely related to the air-breathing land snails, despite a superficial similarity of the shells. The name "Helicinidae" immediately reminds most people of "Helicidae", the most popular group of land snails including e.g. Helix pomatia, but the important two letters "ni" only from the Latin diminutive of the latter name alluding to superficial similarities of otherwise completely different things. Distribution These snails are found in tropical and subtropical areas but they have an odd distribution: they are restricted to the Caribbean islands and some Indo-Pacific and Pacific islands, as well as the edge of the Asian and Australian continents. Some species are found in the southern United States, from Louisiana to Florida; others in Central and South America. Taxonomy Helicinidae belon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columella (gastropod)
The columella (meaning "little column") or (in older texts) pillar is a central anatomical feature of a coiled snail shell, a gastropod shell. The columella is often only clearly visible as a structure when the shell is broken, sliced in half vertically, or viewed as an X-ray image. The columella runs from the apex of the shell to the midpoint of the undersurface of the shell, or the tip of the siphonal canal in those shells which have a siphonal canal. If a snail shell is visualized as a cone of shelly material which is wrapped around a central axis, then the columella more or less coincides spatially with the central axis of the shell. In the case of shells that have an umbilicus, the columella is a hollow structure. The columella of some groups of gastropod shells can have a number of plications or folds (the columellar fold, plaits or plicae), which are usually visible when looking to the inner lip into the aperture of the shell. These folds can be wide or narrow, prominent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lip (gastropod)
In the shell of gastropod mollusks (a snail shell), the lip is the free margin of the peristome (synonym: peritreme) or aperture (the opening) of the gastropod shell. In dextral (right-handed) shells (most snail shells are right-handed), the right side or outer side of the aperture is known as the outer lip (''labrum''). The left side of the aperture is known as the inner lip or columellar lip (''labium'') if there is a pronounced lip there. In those species where there is no pronounced lip, the part of the body whorl that adjoins the aperture is known as the parietal wall. The outer lip is usually thin and sharp in immature shells, and in some adults (e.g. the land snails ''Helicella'' and '' Bulimulus''). However, in some other land snails and in many marine species the outer lip is ''thickened'' (also called ''callused''), or ''reflected'' (turned outwards). In some other marine species it is curled inwards (''inflected''), as in the cowries such as ''Cypraea''. It can also be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in numerous gastropods, but it is also found in shelled cephalopods including ''Nautilus'', ''Spirula'' and the large extinct subclass of cephalopods known as the ammonites. A spiral shell can be visualized as consisting of a long conical tube, the growth of which is coiled into an overall helical or planispiral shape, for reasons of both strength and compactness. The number of whorls which exist in an adult shell of a particular species depends on mathematical factors in the geometric growth, as described in D'Arcy Wentworth Thompson's classic 1917 book ''On Growth and Form'', and by David Raup. The main factor is how rapidly the conical tube expands (or flares-out) over time. When the rate of expansion is low, such that each subsequent whorl is not that much wider than the previous one, then the adult shell has numerous whorls. When the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guadeloupe
Guadeloupe (; ; gcf, label=Antillean Creole, Gwadloup, ) is an archipelago and overseas department and region of France in the Caribbean. It consists of six inhabited islands—Basse-Terre, Grande-Terre, Marie-Galante, La Désirade, and the two inhabited Îles des Saintes—as well as many uninhabited islands and outcroppings. It is south of Antigua and Barbuda and Montserrat, north of the Commonwealth of Dominica. The region's capital city is Basse-Terre, located on the southern west coast of Basse-Terre Island; however, the most populous city is Les Abymes and the main centre of business is neighbouring Pointe-à-Pitre, both located on Grande-Terre Island. It had a population of 384,239 in 2019.Populations légales 2019: 971 Guadeloupe INSEE Like the other overseas departments, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcadia
''Alcadia'' is a genus of tropical and subtropical land snails with an operculum, terrestrial gastropod mollusks in the family Helicinidae. Species Species within the genus ''Alcadia'' include: * ''Alcadia affinis'' C.B. Adams, 1846 * '' Alcadia bermudezi'' Aguayo & Jaume, 1957"Mollusca" . Diversidad Biológica Cubana, accessed 23 March 2011. * '''' Aguayo & Jaume, 1957 * '' Alcadia concinna'' (Gundlach in Pfeiffer, 1857) * '' |
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