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Pyrgulopsis Avernalis
The Moapa pebblesnail also known as the Muddy Valley turban snail, scientific name ''Pyrgulopsis avernalis'', is a species of small freshwater snail with an operculum, an aquatic gastropod mollusk in the family Hydrobiidae. The natural habitat of this species is springs, and it is currently threatened by habitat loss. This species is endemic to the Moapa Valley, Nevada, United States and the common name refers to the Moapa River in Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N .... Description ''Pyrgulopsis avernalis'' is a small snail that has a height of and ovate conical shell. Its differentiated from other ''Pyrgulopsis'' in that its penial filament has a small lobe and large filament with the penial ornament consisting of a small terminal gland, a gland along the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Augustus Pilsbry
Henry Augustus Pilsbry (7 December 1862 – 26 October 1957) was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century. For much of his career, his authority with respect to the classification of certain substantial groups of organisms was unchallenged: barnacles, chitons, North American terrestrial molluscs, terrestrial mollusks, and others. Biography Pilsbry (frequently misspelled ''Pilsbury'') spent his childhood and youth in Iowa. He was called "Harry" Pilsbry then, and developed an early fascination with the limited variety of mollusks he was able to find. He attended the University of Iowa, and received the Bachelor of Science degree there in 1882, but did not immediately find employment in his field of interest. Instead, Henry Pilsbry worked for publishing firms and newspapers for the next several years, but devoted most of his spare time to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat Loss
Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby reducing biodiversity and species abundance. Habitat destruction is the leading cause of biodiversity loss. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they are major threats to the survival of endangered species. Activities such as harvesting natural resources, industrial production and urbanization are human contributions to habitat destruction. Pressure from agriculture is the principal human cause. Some others include mining, logging, trawling, and urban sprawl. Habitat destruction is currently considered the primary cause of species extinction worldwide. Environmental factors can contribute to habitat destruction more indirectly. Geological processes, climate change, introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropods Described In 1935
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 reproduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrgulopsis
''Pyrgulopsis'' is a genus of freshwater snails with a gill and an operculum, aquatic gastropod mollusks in the family Hydrobiidae. Etymology The name ''Pyrgulopsis'' is composed from ''Pyrgula'', another genus of snail, and ''opsis'' = aspect of. Description Generic characters of the genus ''Pyrgulopsis'' are: the shell is minute, conically turreted, somewhat elongated, imperforate and unicarinate. The apex is acute. The aperture is ovate. The edge of the aperture, called the peritreme, is continuous. The operculum is ovate, thin, corneous and spiral, with polar point well forward and approximating the columella. The jaw is thin and membranaceous. The radula is odontophore, with teeth are arranged in transverse rows, according to the formula 3 + 1 + 3. Formula for denticles of rhachidian: . Distribution The distribution of the genus ''Pyrgulopsis'' includes Western and South-western United States. Snails of species in the genus ''Pyrgulopsis'' occur in fresh water and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moapa River
The Muddy River, formerly known as the Moapa River, is a short river located in Clark County, Nevada, Clark County, in southern Nevada, United States. It is in the Mojave Desert, approximately north of Las Vegas, Nevada, Las Vegas. Geography The Muddy River is approximately long. It begins as a series of thermal springs in the Moapa Valley before continuing on its course to Lake Mead, where it drains into the northern arm of the lake near Overton, Nevada. Before the Hoover Dam's construction, the Muddy River flowed into the Virgin River. Near the town of Glendale, Nevada, Glendale the Muddy River collects the flow from the Meadow Valley Wash, forming the principal drainage system for southeastern Nevada. Moapa National Wildlife Refuge The Moapa Valley area is home to a wide variety of rare and endangered species, including fish, invertebrates, birds, and plants. Three endangered fish inhabit the area: the Moapa dace (''Moapa coriacea''), the Virgin River chub (''Gila seminud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevada
Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the List of U.S. states and territories by area, 7th-most extensive, the List of U.S. states and territories by population, 32nd-most populous, and the List of U.S. states and territories by population density, 9th-least densely populated of the U.S. states. Nearly three-quarters of Nevada's people live in Clark County, Nevada, Clark County, which contains the Las Vegas–Paradise, NV MSA, Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City, Nevada, Carson City. Las Vegas is the largest city in the state. Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moapa Valley
Moapa Valley is an unincorporated town in Clark County, Nevada, United States. As of the 2010 census, it had a population of 6,924. The valley in which the community lies, also named Moapa Valley, is about long and lies roughly northwest to southeast. Geography The Muddy River, formerly called the Moapa River, originates from the Warm Springs Natural Area and flows through the valley before emptying into Lake Mead. The communities of Moapa Town, Logandale and Overton are located in the valley. Logandale is about southeast of Moapa Town, and Overton is about southeast of Logandale. Prior to the creation of Lake Mead, Moapa Valley also included the town of St. Thomas, which was abandoned in 1938 due to the rising lake level. Moapa Valley is at an elevation of above sea level. The United States Census Bureau gives the census-designated place (CDP) of Moapa Valley (which may not coincide exactly with the town boundaries) a total area of , of which is land and , or 0.05%, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spring (hydrology)
A spring is a point of exit at which groundwater from an aquifer flows out on top of Earth's crust (pedosphere) and becomes surface water. It is a component of the hydrosphere. Springs have long been important for humans as a source of fresh water, especially in arid regions which have relatively little annual rainfall. Springs are driven out onto the surface by various natural forces, such as gravity and hydrostatic pressure. Their yield varies widely from a volumetric flow rate of nearly zero to more than for the biggest springs. Formation Springs are formed when groundwater flows onto the surface. This typically happens when the groundwater table reaches above the surface level. Springs may also be formed as a result of karst topography, aquifers, or volcanic activity. Springs also have been observed on the ocean floor, spewing hot water directly into the ocean. Springs formed as a result of karst topography create karst springs, in which ground water travels through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Name
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages. Such a name is called a binomial name (which may be shortened to just "binomial"), a binomen, name or a scientific name; more informally it is also historically called a Latin name. The first part of the name – the '' generic name'' – identifies the genus to which the species belongs, whereas the second part – the specific name or specific epithet – distinguishes the species within the genus. For example, modern humans belong to the genus ''Homo'' and within this genus to the species ''Homo sapiens''. ''Tyrannosaurus rex'' is likely the most widely known binomial. The ''formal'' introduction of this system of naming species is credit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic factors will include the availability of food and the presence or absence of predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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