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Fanshell
The Fanshell (''Cyprogenia stegaria'') is a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels. Historically widespread throughout the Ohio, Cumberland, and Tennessee river systems, this species, native to the United States, now occurs in only a few isolated populations and faces a severe threat to its continued existence. It is federally listed as an ''Endangered'' species under the U.S. Endangered Species Act (ESA) due to a dramatic and ongoing decline in its populations and a significant contraction of its historical range. The International Union for Conservation of Nature (IUCN) lists it as ''Critically Endangered''. As a filter-feeding organism, ''Cyprogenia stegaria'' plays an integral role in its riverine ecosystems, contributing to water clarity and nutrient cycling. Its decline, therefore, represents not only the potential loss of a unique species but also a diminishment of these vital ecological functions. Taxonomy and S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constantine Samuel Rafinesque-Schmaltz
Constantine Samuel Rafinesque-Schmaltz (; 22 October 178318 September 1840) was a French early 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimately settling in Ohio in 1815, where he made notable contributions to botany, zoology, and the study of Mound Builders, prehistoric earthworks in North America. He also contributed to the study of ancient Mesoamerican languages, Mesoamerican linguistics, in addition to work he had already completed in Europe. Rafinesque was an eccentric and erratic genius. He was an autodidact, who excelled in various fields of knowledge, as a zoologist, botanist, writer and Polyglot (person), polyglot. He wrote prolifically on such diverse topics as anthropology, biology, geology, and linguistics, but was honored in none of these fields during his lifetime. Indeed, he was an outcast in the American scientific community and his submissions were automati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incomplete Lineage Sorting
Incomplete lineage sorting (ILS) (also referred to as hemiplasy, deep coalescence, retention of ancestral polymorphism, or trans-species polymorphism) is a phenomenon in evolutionary biology and population genetics that results in discordance between species and gene trees. By contrast, complete lineage sorting results in concordant species and gene trees. ILS occurs in the context of a gene in an ancestral species which exists in multiple alleles. If a speciation event occurs in this situation, either complete lineage sorting will occur, and both daughter species will inherit all alleles of the gene in question, or incomplete lineage sorting will occur, when one or both daughter species inherits a subset of alleles present in the parental species. For example, if two alleles of a gene are present and a speciation event occurs, one of the two daughter species might inherit both alleles, but the second daughter species only inherits one of the two alleles. In this case, incomplete l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Licking River (Kentucky)
The Licking River is a partly navigable, U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed June 13, 2011 tributary of the Ohio River in northeastern Kentucky. The river and its tributaries drain much of the region of northeastern Kentucky between the watersheds of the Kentucky River to the west and the Big Sandy River to the east. The North Fork Licking River, in Pendleton County, Kentucky, is one of its tributaries. The South Fork Licking River, in counties including Harrison County, Kentucky, is another. Origin of name The Native Americans of the area called the river ''Nepernine''. When the explorer Thomas Walker first saw it in 1750, he called it Frederick's River. An earlier name given by hunters and frontiersmen, Great Salt Lick Creek, makes reference to the many saline springs near the river that attracted animals to its salt licks. The origin of the present name is unclear, though likely related to the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt River (Kentucky)
The Salt River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed May 13, 2011 river in the U.S. state of Kentucky that drains . It begins near Parksville, Kentucky, rising from the north slope of Persimmon Knob south of KY 300 between Alum Springs and Wilsonville, and ends at the Ohio River near West Point. Taylorsville Lake is formed from the Salt River, and Guist Creek Lake is also in its drainage basin. Annual flooding swells the normally quiet waters to a rapidly flooding torrent, especially along the Rolling Fork, which runs largely along the base of steep, shaly knobs that mark the boundary between the Pennyroyal Region (a Mississippian limestone plateau) to the west and south and the Outer Bluegrass. (See the Ohio River flood of 1937 at Louisville, for an example.) The Taylorsville Lake Dam, built in the early 1970s, has tamed the worst of the floods and changed the nature of the river downstream. Some f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walhonding River
The Walhonding River is a principal tributary of the Muskingum River,Columbia Gazetteer of North America entry long,Ohio Department of Natural Resources ''A Guide to Ohio Streams.'' [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muskingum River
The Muskingum River ( ; ) is a tributary of the Ohio River, approximately long, in southeastern Ohio in the United States. An important commercial route in the 19th century, it flows generally southward through the eastern hill country of Ohio. Via the Ohio, it is part of the Mississippi River drainage basin, watershed. The river is navigable for much of its length through a series of locks and dams. Course The Muskingum is formed at Coshocton, Ohio, Coshocton in east-central Ohio by the confluence of the Walhonding River, Walhonding and Tuscarawas River, Tuscarawas rivers. It flows in a meandering course southward past Conesville, Ohio, Conesville and Dresden, Ohio, Dresden to Zanesville, Ohio, Zanesville, and then southeastward past South Zanesville, Ohio, South Zanesville, Philo, Ohio, Philo, Gaysport, Ohio, Gaysport, Malta, Ohio, Malta, McConnelsville, Ohio, McConnelsville, Beverly, Ohio, Beverly, Lowell, Ohio, Lowell, Stockport, Ohio, Stockport and Devola, Ohio, Devola. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allegheny River
The Allegheny River ( ; ; ) is a tributary of the Ohio River that is located in western Pennsylvania and New York (state), New York in the United States. It runs from its headwaters just below the middle of Pennsylvania's northern border, northwesterly into New York, then in a zigzag southwesterly across the border and through Western Pennsylvania to join the Monongahela River at the Forks of the Ohio at Point State Park in Downtown Pittsburgh, Pennsylvania. The Allegheny River is, by volume, the main headstream of both the Ohio and Mississippi Rivers. Historically, the Allegheny was considered to be the upper Ohio River by both Native Americans and European settlers. This shallow river has been made navigable upstream from Pittsburgh to East Brady, Pennsylvania, East Brady by a series of locks and dams that were constructed during the early 20th century. A 24-mile-long portion of the upper river in Warren County, Pennsylvania, Warren and McKean County, Pennsylvania, McKean c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ohio River
The Ohio River () is a river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing in a southwesterly direction from Pittsburgh, Pennsylvania, to its river mouth, mouth on the Mississippi River in Cairo, Illinois, Cairo, Illinois. It is the third largest river by discharge volume in the United States and the largest tributary by volume of the Mississippi River. It is also the sixth oldest river on the North American continent. The river flows through or along the border of six U.S. state, states, and its drainage basin includes parts of 14 states. Through its largest tributary, the Tennessee River, the basin includes several states of the southeastern United States. It is the source of drinking water for five million people. The river became a primary transportation route for pioneers during the westward expansion of the early U.S. The lower Ohio River just below Louisville was obstructed by rapids known as the Falls of the Oh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclonaias Tuberculata
''Rotundaria tuberculata'', commonly called the purple wartyback, is a freshwater mussel, an aquatic bivalve mollusk. This species is native to eastern North America, generally in the Mississippi River drainage, where it is wide-ranging. It is still common in many areas, particularly in the southern part of its range, but is being negatively impacted by water pollution and channelization. In the Mississippi River drainage, it is threatened by overgrowth of invasive zebra mussels (''Dreissena polymorpha'') and, in Canada, by predation on juvenile mussels and possibly unsuccessful development of larval glochidia on the invasive round goby The round goby (''Neogobius melanostomus'') is a euryhaline bottom-dwelling species of fish of the family (biology), family Gobiidae. It is native to Central Eurasia, including the Black Sea and the Caspian Sea. Round gobies have established larg ... (''Neogobius melanostomus''). It was formerly classified as the sole species in the genus '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrula Pustulosa
''Cyclonaias pustulosa'', the pimpleback, is a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels. This species is native to North America, where it is widespread and common. It has possibly been extirpated from New York, however, and populations in Pennsylvania are critically imperiled, according to NatureServe. The species was formerly classified within the genus ''Quadrula ''Quadrula'' is a genus of freshwater mussels, Aquatic animal, aquatic bivalve mollusks in the family Unionidae native to rivers of the American Midwest and mid-south. All have thick nacreous shells with well-developed hinge teeth, many also wit ...'', and in 2012 it was moved to ''Rotundaria'' based on genetic evidence. References *Williams, J. D.; Bogan, A. E.; Garner, J. T. (2008). Freshwater mussels of Alabama and the Mobile Basin in Georgia, Mississippi and Tennessee. University of Alabama Press, Tuscaloosa. 908 pp. Unionidae Molluscs of No ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hinge Teeth
Hinge teeth are part of the anatomical structure of the inner surface of a bivalve shell, i.e. the shell of a bivalve mollusk. Bivalves by definition have two valves, which are joined together by a strong and flexible ligament situated on the hinge line at the dorsal edge of the shell. In life, the shell needs to be able to open slightly to allow the foot and siphons to protrude, and then close again, without the valves moving out of alignment with one another. To make this possible, in most cases the two valves are articulated using an arrangement of structures known as hinge teeth (often referred to collectively as the "dentition"). Like the ligament, the hinge teeth are also situated along the hinge line of the shell, in most cases. In most families of bivalves, the two valves of the shell are almost perfectly symmetrical with one another along the hinge line, although the placement and shape of the teeth may differ slightly in the left valve and right valve in order for the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nacre
Nacre ( , ), also known as mother-of-pearl, is an organicinorganic composite material produced by some molluscs as an inner shell layer. It is also the material of which pearls are composed. It is strong, resilient, and iridescent. Nacre is found in some of the most ancient lineages of bivalves, gastropods, and cephalopods. However, the inner layer in the great majority of mollusc shells is porcellaneous, not nacreous, and this usually results in a non-iridescent shine, or more rarely in non-nacreous iridescence such as ''flame structure'' as is found in conch pearls. The outer layer of cultured pearls and the inside layer of pearl oyster and freshwater pearl mussel shells are made of nacre. Other mollusc families that have a nacreous inner shell layer include marine gastropods such as the Haliotidae, the Trochidae and the Turbinidae. Physical characteristics Structure and appearance Nacre is composed of hexagonal platelets, called tablets, of aragonite (a form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
