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Clavatula Helena
''Clavatula helena'' is a species of sea snail, a marine gastropod mollusk in the family Clavatulidae. Description The size of an adult shell varies between 30 mm and 40 mm. The fusiform shell is moderately long. The ground color of the shell is yellow, superimposed with blotches and streaks of chestnut brown. The space between the sutures is brown in the anterior half. The teleoconch is flattened with a narrow keel posterior to the broad, anal sinus. The anterior half of the teleoconch has between 8 and 12 feeble axial ribs. All over the spire are very fine growth lines. The periphery of the body whorl is well rounded. The aperture is elongately oval. The thick outer lip is notched at the anal sinus. The parietal wall shows a very thick callus. The siphonal canal is very short. Distribution This marine species occurs in Jeffrey's Bay - Tsitsikamma, South Africa References * Kilburn, R.N. (1985). ''Turridae (Mollusca: Gastropoda) of southern Africa and Mozam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Bartsch
Paul Bartsch (14 August 1871 Tuntschendorf, Silesia – 24 April 1960 McLean, Virginia) was an American malacologist and carcinologist. He was named the last of those belonging to the "Descriptive Age of Malacology". Early life Bartsch emigrated with his parents to the U.S.A in 1880, first to Missouri and then to Burlington, Iowa. As a child, he took up jobs in his spare time in several employments. He soon took an interest in nature, first by keeping a small menagerie at home, and during his high school years, collecting birds and preparing skins. He established a natural-history club in his home with a little museum and a workshop. By the time he went to the University of Iowa in 1893, he had collected 2,000 skins. Among his professors at the university were the University of Iowa were the geologist Samuel Calvin, botanists Thomas H. Macbride and Bohumil Shimek, and the zoologist Charles C. Nutting. He graduated from the university with a B.S. in 1896, and M.S. in 1899, a ... [...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] |
Endemic Molluscs Of South Africa
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] |
Tsitsikamma
The Tsitsikamma National Park is a protected area on the Garden Route, Western Cape and Eastern Cape, South Africa. It is a coastal reserve well known for its indigenous forests, dramatic coastline, and the Otter Trail. On 6 March 2009 it was amalgamated with the Wilderness National Park and various other areas of land to form the Garden Route National Park. The park covers an long stretch of coastline. Nature's Valley is at the western end of the park, and the main accommodation is at Storms River Mouth. Near the park is the Bloukrans Bridge, the world's highest bridge bungee jump at . The word "Tsitsikamma" originates from the Khoekhoe language ''tse-tsesa'', meaning "clear", and ''gami'', meaning "water", probably referring to the clear water of the Tsitsikamma River. Other meanings are 'place of much water' and 'waters begin'. Camps Storms River Various amenities, including a restaurant, shop, chalets, campsite and caravan park, information centre, adventure boo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeffrey's Bay
Jeffreys Bay ( af, Jeffreysbaai, nicknamed J-bay) is a town of 27,107 inhabitants as of the 2011 census in the Eastern Cape province of South Africa. It Is the seat of the Kouga municipality and is famous amongst surfers as a surf capital due to the right-hand point break at Supertubes Beach. The town is situated just off the N2 Highway, about 75 kilometres southwest of Port Elizabeth. History Jeffreys Bay is named after the senior partner of the firm Jeffrey & Glendinnings that opened a store in 1849 on the location where the town is today. Jeffrey is believed to be the first person to have settled there. In the late 1960s and early 1970s, Jeffreys Bay was known as a hippie hangout, where the now-burgeoning surf community originated. Jeffreys Bay has grown from a sleepy little fishing town over the past few years and is one of the fastest expanding urban areas in the country. Jeffreys Bay as a surfing destination was made famous by Bruce Brown's movie "The Endless Summer" ... [...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] |
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] |
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] |
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] |
Teleoconch
The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group. Shell layers The gastropod shell has three major layers secreted by the mantle. The calcareous central layer, tracum, is typically made of calcium carbonate precipitated into an organic matrix known as conchiolin. The outermost layer is the periostra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (gastropod)
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 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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