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Astraea Heliotropium
''Astraea heliotropium'', common name the sunburst star turban or the circular saw shell, is a large sea snail, a marine gastropod mollusc of the family Turbinidae, the turbans and star snails.WoRMS (2010). ''Astraea heliotropium'' (Martyn, 1784). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=404992 on 2011-03-08 This large species was brought to Europe for the first time by the famous Captain Cook. Shell description The height of the shell is up to 60 mm, and the width is up to 120 mm. The large shell has a depressed-conic shape. Below widely it is umbilicate and concave. The spire is dome-shaped, and consists of 5 convex whorls. The suture is rendered zigzag by the prominent compressed triangular recurved vaulted spines which arm the acutely carinated periphery. The whorls above and below contain numerous spiral series of granules. The wide umbilicus is deep, and coarsely obliquely striate within. The a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Department Of Conservation (New Zealand)
The Department of Conservation (DOC; Māori language, Māori: ''Te Papa Atawhai'') is the public service department of New Zealand charged with the conservation of New Zealand's natural and historical heritage. An advisory body, the New Zealand Conservation Authority, New Zealand Conservation Authority (NZCA) is provided to advise DOC and its ministers. In addition there are 15 conservation boards for different areas around the country that provide for interaction between DOC and the public. Functions and history Overview The department was formed on 1 April 1987, as one of several reforms of the public service, when the ''Conservation Act 1987'' was passed to integrate some functions of the Department of Lands and Survey, the New Zealand Forest Service, Forest Service and the New Zealand Wildlife Service, Wildlife Service. This act also set out the majority of the department's responsibilities and roles. As a consequence of Conservation Act all Crown land in New Zealand ... [...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 fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropods Described In 1784
Gastropods (), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and from the land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, land snails and slugs. The class Gastropoda is a diverse and highly successful class of mollusks within the phylum Mollusca. It 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic Fauna Of New Zealand
Endemism is the state of a species being found only 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 also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or becomin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astraea (gastropod)
''Astraea'' is a genus of medium to large sea snails, marine (ocean), marine gastropod mollusks in the family Turbinidae, the turban snails.Bouchet, P. (2012). Astraea Röding, 1798. Accessed through: World Register of Marine Species aWoRMS taxon detailson 2012-03-15 Etymology The Latin genus ''Astraea'' means ''star'', with reference to the star-shape of these snails, also commonly called ''star shells''. Description Shells of species within this genus can reach a size of about . They have the appearance of a smooth conical shell. The outer edges of the coiled Whorl (mollusc), whorls are quite flattened, with prominent axial sculpture. Below widely, it is umbilicate and concave. Species Extant species within this genus include: *''Astraea heliotropium'' (Martyn, 1784) Fossil records This genus is known in the fossil records from the Paleocene to the Quaternary (age range: from 61.7 to 0.0 million years ago). Fossils of species within this genus have been found in the sedimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur William Baden Powell
Arthur William Baden Powell (4 April 1901 – 1 July 1987) was a New Zealand malacologist, naturalist and palaeontologist, a major influence in the study and classification of New Zealand molluscs through much of the 20th century. He was known to his friends and family by his third name, "Baden". Biography Early life The name Baden had been a given name in a Powell family since 1731, when Susannah Powell née Thistlethwayte (1696–1762) gave to her child (1731–1792) the maiden name of her mother, Susannah Baden (1663–1692). The name Baden, particularly when associated with the surname Powell, became famous in 1900–1901, the year Arthur William Baden Powell was born, because of the siege of Mafeking, the most famous British action in the Second Boer War, which turned the British commander of the besieged, Robert Baden-Powell, into a national hero. Throughout the British Empire, babies were named after him. No family connection has yet been established between Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
Endemism is the state of a species being found only 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 also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peristome (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 e ... [...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 (bivalve), 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 (mollusc), apex of the shell is called an orifice, and in the Haliotidae (abalone) where the row of respiratory openings in the shell are also called orifices. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral or whorled 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 Cone (geometry), conical tube, the growth of which is coiled into an overall Helix, 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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Martyn (zoologist)
Thomas Martyn (probably 1760 – 1816) was an English zoologist, conchologist and entomologist. There is a botanist of the same name who lived in the same period. Life Little is known about Thomas Martyn's life, and nothing is known 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 be derived from Aerostatic Globes. With a Print of an Aerostatic Globe … originally designed in 1783'', 1784. * ''The Universal Conchologist, exhibiting the figure of every known Shell'', with second title ''Figures of non-descript Shells c ... [...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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
