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Leptoxis Carinata
''Leptoxis carinata'', common name the crested mudalia, is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Pleuroceridae. Shell description ''Leptoxis carinata'' has a strong globose shell, with highly variable sculpture. In various creeks and rivers throughout its range, populations may be found with spiral cords, a single carina or keel, variously developed, or lacking sculpture. Distribution This species occurs in unpolluted large creeks and high-gradient rivers in the Atlantic drainages of the United States, from New York to North Carolina. Ecology Habitat ''Leptoxis carinata'' is found in high-gradient streams, generally in the faster flowing riffles and drops, where it clings firmly to large stones and bedrock exposures. Life cycle ''Leptoxis carinata'' is semelparous biennial. This species, unlike softer shelled physid snails, grows very slowly, and has the lowest intrinsic rate of increase (this means that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Guillaume Bruguière
Jean Guillaume Bruguière (19 July 1749 – 3 October 1798) was a French physician, zoologist and diplomat. Biography Bruguière was born in Montpellier on 19 July 1749.Comptes rendus du Congrès national des sociétés savantes: Section des sciences. (1961) page 173. Jean-Guillaume Bruguière (1749-1798) et Guillaume-Antoine Olivier (1756-1814), médecins naturalistes et voyageurs. Jean Théodoridès He was a doctor, connected to the University of Montpellier. He was interested in invertebrates, mostly snails (gastropods). He accompanied the explorer Kerguelen-Trémarec on his first voyage to the Antarctic in 1773. In 1790 he accompanied the entomologist Olivier on an expedition to Persia, but his poor health didn't allow him to continue. In 1792, although he was ill, he visited the Greek archipelago and the Middle East, together with the entomologist Guillaume-Antoine Olivier. He was asked by the French Directoire to try to set up a Franco-Persian alliance, but was unsuccess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrasted with the scientific name for the same organism, which is Latinized. A common name is sometimes frequently used, but that is not always the case. In chemistry, IUPAC defines a common name as one that, although it unambiguously defines a chemical, does not follow the current systematic naming convention, such as acetone, systematically 2-propanone, while a vernacular name describes one used in a lab, trade or industry that does not unambiguously describe a single chemical, such as copper sulfate, which may refer to either copper(I) sulfate or copper(II) sulfate. Sometimes common names are created by authorities on one particular subject, in an attempt to make it possible for members of the general public (including such interested par ... [...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] |
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] |
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] |
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] |
Pleuroceridae
Pleuroceridae, common name pleurocerids, is a family of small to medium-sized freshwater snails, aquatic gilled gastropod mollusks in the superfamily Cerithioidea.These snails have an operculum and typically a robust high-spired shell. Reproduction is iteroparous, and juvenile snails emerge from eggs laid on a firm surface by a gonochoristic female. There is no veliger stage. Distribution As currently defined, this family is confined entirely to eastern North American fresh waters. Similar snails formerly classified with Pleuroceridae, but now assigned to other families are widespread in temperate and tropical parts of Southern and Eastern Asia, and Africa. Most require unpolluted rivers and streams, but a few are adapted to living in lakes or reservoirs. Taxonomy 2005 taxonomy The following two subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005): * Pleurocerinae P. Fischer, 1885 - synonyms: Ceriphasiinae Gill, 1863; Strepomatidae Haldeman, 1864 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semelparous
Semelparity and iteroparity are two contrasting reproductive strategies available to living organisms. A species is considered semelparous if it is characterized by a single reproductive episode before death, and iteroparous if it is characterized by multiple reproductive cycles over the course of its lifetime. Iteroparity can be further divided into continuous iteroparity (primates including humans and chimpanzees) and seasonal iteroparity (birds, dogs, etc.) Some botanists use the parallel terms monocarpy and polycarpy. (See also plietesials.) In truly semelparous species, death after reproduction is part of an overall strategy that includes putting all available resources into maximizing reproduction, at the expense of future life (see § Trade-offs). In any iteroparous population there will be some individuals who die between their first and second reproductive episodes, but unless this is part of a syndrome of programmed death after reproduction, this would not be called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physidae
Physidae, common name the bladder snails, is a monophyletic taxonomic family of small air-breathing freshwater snails, aquatic pulmonate gastropod molluscs in the superfamily Lymnaeoidea .MolluscaBase eds. (2021). MolluscaBase. Physidae Fitzinger, 1833. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=160452 on 2021-06-26 Overview These fresh water snails are present in aquariums and ponds, as well as in wild areas. They are commonly referred to as tadpole snails or pouch snails. They eat algae, diatoms and detritus including dead leaves. The populations are regulated by the abundance of food and space. They are widespread, abundant, and tolerant to pollution. These snails are common in the North Temperate to Arctic Zones and throughout the Americas, in readily accessible habitats such as ditches, ponds, lakes, small streams, and rivers. The family has been recognized since the 19th century, and yet there has been no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Dynamics
Population dynamics is the type of mathematics used to model and study the size and age composition of populations as dynamical systems. History Population dynamics has traditionally been the dominant branch of mathematical biology, which has a history of more than 220 years,Malthus, Thomas Robert. An Essay on the Principle of Population: Library of Economics although over the last century the scope of mathematical biology has greatly expanded. The beginning of population dynamics is widely regarded as the work of Malthus, formulated as the Malthusian growth model. According to Malthus, assuming that the conditions (the environment) remain constant ('' ceteris paribus''), a population will grow (or decline) exponentially. This principle provided the basis for the subsequent predictive theories, such as the demographic studies such as the work of Benjamin Gompertz and Pierre François Verhulst in the early 19th century, who refined and adjusted the Malthusian demographic model. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elimia Virginica
''Elimia virginica'', common names the Piedmont elimia or Virginia river snail, is a species of freshwater snail with an operculum, an aquatic gastropod mollusc in the family Pleuroceridae. Distribution Indigenous distribution ''Elimia virginica'' is native to the United States east of the continental divide. The species occurs in large Atlantic coast rivers in eastern North America, from Massachusetts to Virginia. The northeastern limit of the native range of the species is the lower Connecticut River. The distribution of this species is shrinking in the native Connecticut River, and it is considered rare in Connecticut. Its conservation status in the Connecticut River Watershed is W1 (''"a rare species, with 20 or fewer known occurrences in the watershed states"''). The conservation status of ''Elimia virginica'' according to NatureServe, is as follows: * United States of America – secure. ** Massachusetts – presumed extirpated. ** Connecticut – critically imperile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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