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Anacithara Brevicostata
''Anacithara brevicostata'' is a species of sea snail, a marine gastropod mollusk in the family Horaiclavidae.WoRMS (2015). Anacithara brevicostata Hedley, 1922. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=432942 on 2016-12-18 Description The length of the shell attains 4.5 mm, its diameter 2 mm. (Original description) The small, thin shell has an elongate-ovate shape. Its colour is pale buff, with a narrow subsutural baud. It contains six rounded whorls, including the two whorls in the protoconch, which is smooth, turbinate, and slightly tilted. The ribs are rather prominent, rounded and broader than their interstices. They number nine on the penultimate whorl and on the body whorl ten.;These are spaced more widely than those above, commencing at the suture and terminating rather abruptly at the periphery. The spirals are even, comparatively coarse, and close-set threads, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Hedley
Charles Hedley (27 February 1862 – 14 September 1926) was a naturalist, specifically a malacologist. Born in Britain, he spent most of his life in Australia. He was the winner of the 1925 Clarke Medal. Early life Hedley was born in the vicarage at Masham, Yorkshire, England, the son of the Rev. Canon Thomas Hedley and his wife Mary, ''née'' Bush. On account of delicate health Hedley had only two years at Eastbourne College, but his education was continued by his father, a fellow of Trinity College, Cambridge. He was mainly educated in the south of France; from boyhood he collected mollusc shells, and was greatly influenced by a French work on molluscan anatomy. In France he met George French Angas who gave him a letter of introduction to Dr. George Bennett of Sydney. Exploring in Oceania In 1881 Hedley went to New Zealand and in September 1882 to Sydney. He was suffering from asthma and after trying the dry interior found he was in better health when near the sea. He took u ... [...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] |
Anacithara
''Anacithara'' is a genus of sea snails, marine gastropod mollusks in the family Horaiclavidae.Bouchet, P. (2015). Anacithara Hedley, 1922. In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=432392 on 2016-12-17 This genus was previously classified under the subfamily Mangeliinae, but transferred to Crassispirinae by Kilburn in 1994 In 2011 it was brought into the family Horaiclavidae by Bouchet P., Kantor Yu.I., Sysoev A. & Puillandre N. in their publication "A new operational classification of the Conoidea" Bouchet P., Kantor Yu.I., Sysoev A. & Puillandre N. (2011). "A new operational classification of the Conoidea". ''Journal of Molluscan Studies'' 77: 273-308. . Description This genus consists of small claviform shells (3–10 mm) which resemble ''Eucithara'' Fischer, 1883 (family Mangeliidae) in their upper whorls and sculpture, but differ in their wide aperture, devoid of teeth on eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queensland
) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_date = Colony of Queensland , established_title2 = Separation from New South Wales , established_date2 = 6 June 1859 , established_title3 = Federation , established_date3 = 1 January 1901 , named_for = Queen Victoria , demonym = , capital = Brisbane , largest_city = capital , coordinates = , admin_center_type = Administration , admin_center = 77 local government areas , leader_title1 = Monarch , leader_name1 = Charles III , leader_title2 = Governor , leader_name2 = Jeannette Young , leader_title3 = Premier , leader_name3 = Annastacia Palaszczuk ( ALP) , legislature = Parliament of Queensland , judiciary = Supreme Court of Queensland , national_representation = Parliament of Australia , national_representation_type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
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] |
Siphonal Canal
The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is drawn into the mantle cavity and over the gill and which serves as a chemoreceptor to locate food. Siphonal canals allow for active transport of water to sensory organs inside the shell. Organisms without siphonal canals in their shells rely on passive or diffuse transport or water into their shell. Those with siphonal canals have a direct inhalant stream of water that interacts with sensory organs to detect concentration and direction of a stimulus, such as food or mates. In certain groups of carnivorous snails, where the siphon is particularly long, the structure of the shell has been modified in order to house and protect the soft structure of the siphon. Thus the siphonal canal is a semi-tubular extension of the aperture of the shell th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varix (mollusc)
A varix () is an anatomical feature of the shell of certain sea snails, marine gastropod molluscs. Gastropods whose shells have varices are primarily families and species within the taxonomic groups Littorinimorpha and Neogastropoda. The varix is a thickened axial ridge, a subcylindrical protrusion, in the shell which exists in some families of marine gastropods. It is an important shell character in generic classification. A varix is located at intervals around the whorl, and is formed by considerable thickening of the outer lip during a resting stage in the growth of the shell. In other words, in gastropods whose shells have varices, the shells are characterised by episodic growth - the shell grows in spurts, and during the resting phase the varix forms. In many gastropod whose shells have varices, for example the Cassinae, the varix is essentially merely a thickening and swelling of the shell at that point. But in some genera within the family Muricidae, such as ''Chicoreu ... [...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] |
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] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...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] |
Horaiclavidae
Horaiclavidae is a family of predatory sea snails, marine gastropod mollusks in the superfamily Conoidea. In 2011 this family was split off from the family Pseudomelatomidae (formerly the subfamily Crassispirinae McLean, 1971) by Bouchet P., Kantor Yu.I., Sysoev A. & Puillandre N. in their publication "A new operational classification of the Conoidea". It forms a clade together with the family Clavatulidae. It has many characters in common with the family Pseudomelatomidae, except the smaller shell with a low spire, the short siphonal canal and a weak or absent spiral sculpture. The radular formula is 1-0-0-0-1, but some species in this family lack a radula. Genera Genera within the family Horaiclavidae include: * '' Anacithara'' Hedley, 1922 * '' Anguloclavus'' Shuto, 1983 * '' Aoteadrillia'' Powell, 1942 * '' Asperosculptura'' Ardovini, Poppe & Tagaro, 2021 * '' Austrocarina'' Laseron, 1954 * '' Austrodrillia'' Hedley, 1918 * ''Buchema'' Corea, 1934 * '' Carinapex'' Dall, 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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