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Cantharidus Opalus Opalus
''Cantharidus opalus'', common name the opal top shell or in the Māori language matangongore, is a species of large sea snail, a marine gastropod mollusc in the family Trochidae, the top snails.Rosenberg, G. (2012). Cantharidus opalus (Martyn, 1784). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=590656 on 2012-11-27 Description The length of the shell varies between 23 mm and 45 mm. The large, imperforate shell has an elevated conical shape. It is angular at the periphery, solid, but not very thick. Its spiral sculpture, not conspicuous, subobsolete. It is obsoletely distantly spirally grooved. These number about 7 on the penultimate whorl, mostly indistinct, crossed by more or less distinct oblique growth lines . The base of the shell contains about 5 spiral separated narrow ridges, often inconspicuous. The colour is whitish, tinged with blue on the body whorl and yellowish or pinkish on the spire, all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Martyn (zoologist)
Thomas Martyn (probably 1760 – 1816) was an English zoologist, conchologist and entomologist Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach .... He should not be confused with the botanist of the same name. Life Little is known about Thomas Martyn's life and nothing about his parents, his wife and his children. It is believed that he was born in 1760 in Coventry. Later he lived at several addresses in London. At 10 Great Marlborough Street, Westminster he established an academy for the painting of Natural History. Besides English, Martyn spoke French and Latin. Works In 1784, Martyn started his major work, ''The Universal Conchologist'', which he completed and published in London in 1784, dedicating it to the King. His publications included: * ''Hints of important Uses to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Whorl
The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the body whorl, or last whorl, is the most recently formed and largest whorl (or revolution) of a spiral or helical shell, terminating in the aperture. It is called the "body whorl" because most of the body of the soft parts of the animal fits into this whorl. The proportional size of the body whorl in gastropod shells differs greatly according to the actual shell morphology. For shells in which the rate of whorl expansion of each revolution around the axis is very high, the aperture and the body whorl are large, and the shell tends to be low spired. The shell of the abalone is a good example of this kind of shell. The opposite tendency can sometimes create a high spire with very little whorl increase per revolution. In these instances, e.g. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cantharidus
''Cantharidus'', common name the kelp shells, is a genus of sea snails, marine gastropod molluscs of the family Trochidae, the top shells.Rosenberg, G.; Bouchet, P. (2013). Cantharidus Montfort, 1810. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=204763 on 2014-01-12 Description The shell has an ovate-conic or pyramidal shape. It is imperforate, smooth or spirally sculptured outside, brilliantly iridescent within. The colors are generally bright and variegated. The aperture is less than half the length of shell, longer than wide, ovate. The columella is usually more or less folded or toothed near the base. The central tooth of the radula has a body with broadly expanded supporting wings, a narrowed peduncle or neck, which bears a simple cusp. This peduncle has on each side delicate wings. The lateral teeth number five on each side and have as peculiarity that they increase in size from the inner to the outer one. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HarperCollins
HarperCollins Publishers LLC is one of the Big Five English-language publishing companies, alongside Penguin Random House, Simon & Schuster, Hachette, and Macmillan. The company is headquartered in New York City and is a subsidiary of News Corp. The name is a combination of several publishing firm names: Harper & Row, an American publishing company acquired in 1987—whose own name was the result of an earlier merger of Harper & Brothers (founded in 1817) and Row, Peterson & Company—together with Scottish publishing company William Collins, Sons (founded in 1819), acquired in 1989. The worldwide CEO of HarperCollins is Brian Murray. HarperCollins has publishing groups in the United States, Canada, the United Kingdom, Australia, New Zealand, Brazil, India, and China. The company publishes many different imprints, both former independent publishing houses and new imprints. History Collins Harper Mergers and acquisitions Collins was bought by Rupert Murdoch's News Corpora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs ... [...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] |
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where the head-foot part of the body of the animal emerges for locomotion, feeding, etc. The term ''aperture'' is used for the main opening in gastropod shells, scaphopod shells, and also for ''Nautilus'' and ammonite shells. The word is not used to describe bivalve shells, where a natural opening between the two shell valves in the closed position is usually called a ''gape''. Scaphopod shells are tubular, and thus they have two openings: a main anterior aperture and a smaller posterior aperture. As well as the aperture, some gastropod shells have additional openings in their shells for respiration; this is the case in some Fissurellidae (keyhole limpets) where the central smaller opening at the apex of the shell is called an orifice, and in the Haliotidae (abalones) where the row of respiratory openings in the shell are also called orifices. In gastropods In some prosobranch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (anatomy)
In anatomy, a suture is a fairly rigid joint between two or more hard elements of an organism, with or without significant overlap of the elements. Sutures are found in the skeletons or exoskeletons of a wide range of animals, in both invertebrates and vertebrates. Sutures are found in animals with hard parts from the Cambrian period to the present day. Sutures were and are formed by several different methods, and they exist between hard parts that are made from several different materials. Vertebrate skeletons The skeletons of vertebrate animals (fish, amphibians, reptiles, birds, and mammals) are made of bone, in which the main rigid ingredient is calcium phosphate. Cranial sutures The skulls of most vertebrates consist of sets of bony plates held together by cranial sutures. These sutures are held together mainly by Sharpey's fibers which grow from each bone into the adjoining one. Sutures in the ankles of land vertebrates In the type of crurotarsal ankle which is found ... [...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] |
Protoconch
A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called "nucleus". The protoconch may sometimes consist of several whorls, but when this is the case, the whorls show no growth lines. The whorls of the adult shell, which are formed after the protoconch, are known as the teleoconch. The teleoconch starts forming when the larval gastropod becomes a juvenile, and the protoconch may dissolve. Quite often there is a visible line of demarcation where the protoconch ends and the teleoconch begins, and there may be a noticeable change in sculpture, or a sudden appearance of sculpture at that point. In some gastropod groups (such as the Architectonicidae), the teleoconch whorls spiral in the opposite direction to the protoconch. In those cases, the shell is called heterostrophic. In species which ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spire (mollusc)
A spire is a part of the coiled shell of molluscs. The spire consists of all of the whorls except for the body whorl. Each spire whorl represents a rotation of 360°. A spire is part of the shell of a snail, a gastropod mollusc, a gastropod shell, and also the whorls of the shell in ammonites, which are fossil shelled cephalopods. In textbook illustrations of gastropod shells, the tradition (with a few exceptions) is to show most shells with the spire uppermost on the page. The spire, when it is not damaged or eroded, includes the protoconch (also called the nuclear whorls or the larval shell), and most of the subsequent teleoconch whorls (also called the postnuclear whorls), which gradually increase in area as they are formed. Thus the spire in most gastropods is pointed, the tip being known as the "apex". The word "spire" is used, in an analogy to a church spire or rock spire, a high, thin, pinnacle. The "spire angle" is the angle, as seen from the apex, at which a spire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
