|
Lunule (bivalve)
A lunule (from the Latin meaning small moon or crescent moon) is an anatomical feature which is found in the exterior surface of the shells of some species of clams, bivalve mollusks, as for example in the family Veneridae and in the genus '' Ascetoaxinus''. The lunule is a well-defined area near the hinge line A hinge line is an imaginary longitudinal line along the dorsal edge of the shell of a bivalve mollusk where the two valves hinge or articulate. The hinge line can easily be perceived in these images of a mussel shell and an ark shell.Invertebrat ... of the shell, anterior to the beaks. Website conchs.org, The Conchological Society of Great Britain and Ireland, Molluscs, Glossary, Advanced glossary of molluscan terminology, Lunule, by Steve Wilkinson, 5 November 201Accessed 2014.12.9 Despite the name, a lunule is not always in the shape of a crescent moon. Details of the lunule are sometimes an important diagnostic feature in identifying a bivalve shell. References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercenaria Campechiensis Valve View
''Mercenaria'' is a genus of edible saltwater clams, marine bivalve molluscs in the family Veneridae, the Venus clams. The genus ''Mercenaria'' includes the quahogs, consisting of ''Mercenaria mercenaria'', the northern quahog or hard clam, and ''M. campechiensis'', the southern quahog. These two species commonly hybridise where their ranges overlap. Mercenaria mercenaria is further subdivided in the marketplace and thence in the kitchen by size: the largest being the quahog or chowder clam, then smaller cherrystones, and smallest littlenecks; some markets also differentiate top necks which are intermediate in size between cherrystones and littlenecks. The smaller clams are eaten raw throughout New England, New York, and New Jersey; the larger clams are more suited for cooking. Other species within the genus include the venus clam ''M. stimpsoni'' found in north Pacific waters. All these species were formerly placed in the related genus ''Venus''. Species The World Regist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusc
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Veneridae
The Veneridae or venerids, common name: Venus clams, are a very large family of minute to large, saltwater clams, marine bivalve molluscs. Over 500 living species of venerid bivalves are known, most of which are edible, and many of which are exploited as food sources. Many of the most important edible species are commonly known (in the USA) simply as "clams". Venerids make up a significant proportion of the world fishery of edible bivalves. The family includes some species that are important commercially, such as (in the USA) the hard clam or quahog, ''Mercenaria mercenaria''. Taxonomy The classification within the family Veneridae has been controversial at least since the 1930s. Molecular approaches show that much of this traditional classification is unnatural. Some common species have been moved between genera (including genera in different subfamilies) because of repeated attempts to bring a more valid organization to the classification or taxonomy of the family, there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascetoaxinus
''Ascetoaxinus'' is a genus of saltwater clams, marine bivalve molluscs in the family Thyasiridae. The shells of species in this genus have a lunule with a scalloped margin. The genus was first described in 2014 by Graham Oliver of the National Museum of Wales and Melissa Frey, curator of invertebrates at the Royal British Columbia Museum Founded in 1886, the Royal British Columbia Museum (sometimes referred to as Royal BC Museum) consists of The Province of British Columbia's natural and human history museum as well as the British Columbia Provincial Archives. The museum is loca .... The genus consists of the following species: *'' Ascetoaxinus quatsinoensis'' Oliver and Frey, 2014 *'' Ascetoaxinus ovoidea'' (Dall, 1890), formerly known as '' Cryptodon ovoideus'' Dall, 1890 References External links * Images of ''Ascetoaxinus quatsinoensis'hereanhere Thyasiridae Bivalve genera {{Bivalve-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hinge Line
A hinge line is an imaginary longitudinal line along the dorsal edge of the shell of a bivalve mollusk where the two valves A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ... hinge or articulate. The hinge line can easily be perceived in these images of a mussel shell and an ark shell.Invertebrate Paleobiology on-line syllabus on Bivalves, by Dr. Burt Carter, Georgia Southwestern State University, at: http://itc.gsw.edu/faculty/bcarter/paleo/labs/moll/biv2.htm The hinge teeth, structures which control the articulation of the valves, are often but not always situated along the hinge line. References Mollusc shells {{bivalve-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chionopsis Intapurpurea Valve View
''Chionopsis'', is a genus of saltwater clam, a marine bivalve mollusc 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 esti ... in the family Veneridae, the venus clams. Species Species within this genus include: * '' Chionopsis amathusia'' (Philippi, 1844) * '' Chionopsis crenata'' (Gmelin, 1791) * '' Chionopsis crenifera'' (G. B. So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve Anatomy
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed of calcium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
