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Splendrillia Lucida
''Splendrillia lucida'' is a species of sea snail, a marine gastropod mollusk in the family Drilliidae. Description The length of the shell attains 8 mm, its diameter 3 mm. (Original description) The shell is acuminately fusiform, very smooth and glittering. It is white, slightly and irregularly marbled with pale brown here and there between the ribs and especially behind the outer lip. The suture is distinct. The protoconch is blunt and rounded, almost like that of ''Pyramidella'' in character. The shell contains 8 to 9 whorls. The two first are smooth and embryonal, the others divided with a deeply incised groove beneath the suture, longitudinally, thickly, distantly ribbed. The body whorl contains 9 ribs, transversely striated at its base, gibbous posteriorly, with a rather considerable smooth space behind the marginal varix. Next the suture the upper part of the ribs, cut off by the deep spiral groove, have the appearance of a row of granules. The columella and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), 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 reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), 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 binomial nomenclature, 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 specifi ... [...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 ''C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andaman Islands
The Andaman Islands () are an archipelago in the northeastern Indian Ocean about southwest off the coasts of Myanmar's Ayeyarwady Region. Together with the Nicobar Islands to their south, the Andamans serve as a maritime boundary between the Bay of Bengal to the west and the Andaman Sea to the east. Most of the islands are part of the Andaman and Nicobar Islands, a Union Territory of India, while the Coco Islands and Preparis Island are part of the Yangon Region of Myanmar. The Andaman Islands are home to the Andamanese, a group of indigenous people that includes a number of tribes, including the Jarawa and Sentinelese. While some of the islands can be visited with permits, entry to others, including North Sentinel Island, is banned by law. The Sentinelese are generally hostile to visitors and have had little contact with any other people. The government protects their right to privacy. History Etymology In the 13th century, the name of Andaman appears in Late M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bay Of Bengal
The Bay of Bengal is the northeastern part of the Indian Ocean, bounded on the west and northwest by India, on the north by Bangladesh, and on the east by Myanmar and the Andaman and Nicobar Islands of India. Its southern limit is a line between Sangaman Kanda, Sri Lanka, and the north westernmost point of Sumatra, Indonesia. It is the largest water region called a bay in the world. There are countries dependent on the Bay of Bengal in South Asia and Southeast Asia. During the existence of British India, it was named as the Bay of Bengal after the historic Bengal region. At the time, the Port of Kolkata served as the gateway to the Crown rule in India. Cox's Bazar, the longest sea beach in the world and Sundarbans, the largest mangrove forest and the natural habitat of the Bengal tiger, are located along the bay. The Bay of Bengal occupies an area of . A number of large rivers flow into the Bay of Bengal: the Ganges– Hooghly, the Padma, the Brahmaputra– Yamuna, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Persian Gulf
The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a mediterranean sea in Western Asia. The body of water is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.United Nations Group of Experts on Geographical NameWorking Paper No. 61, 23rd Session, Vienna, 28 March – 4 April 2006. accessed October 9, 2010 It is connected to the Gulf of Oman in the east by the Strait of Hormuz. The Shatt al-Arab river delta forms the northwest shoreline. The Persian Gulf has many fishing grounds, extensive reefs (mostly rocky, but also coral), and abundant pearl oysters, however its ecology has been damaged by industrialization and oil spills. The Persian Gulf is in the Persian Gulf Basin, which is of Cenozoic origin and related to the subduction of the Arabian Plate under the Zagros Mountains. The current floo ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptadrillia Quisqualis
''Leptadrillia quisqualis'' is a species of sea snail, a marine gastropod mollusk in the family Drilliidae. Description The shell grows to a length of 11 mm. The white shell is obtusely angulated, smooth above the angle, which is nodose by the termination of short longitudinal ribs. Distribution This species occurs in the demersal zone of the Pacific Ocean off Nicaragua. ''Clathurella quisqalis'' (Hinds, 1843) has also been described from Darnley Island, Torres Straits The Torres Strait (), also known as Zenadh Kes, is a strait between Australia and the Melanesian island of New Guinea. It is wide at its narrowest extent. To the south is Cape York Peninsula, the northernmost extremity of the Australian ma ....Brazier, J. 1876. ''A list of the Pleurotomidae collected during the Chevert expedition, with the description of the new species''. Proceedings of the Linnean Society of New South Wales 1: 151–162/ref> References Tucker, J.K. 2004 ''Catalog of recent an ... [...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 pros ... [...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, promine ... [...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 whorl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Snail
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell. Definition Determining whether some gastropods should be called sea snails is not always easy. Some species that live in brackish water (such as certain neritids) can be listed as either freshwater snails or marine snails, and some species that live at or just above the high tide level (for example species in the genus '' Truncatella'') are sometimes considered to be sea snails and sometimes listed as land snails A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known .... Anatomy Sea snails are a very large group o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramidella
''Pyramidella'' is a genus of minute to medium-sized sea snails, marine gastropod mollusk in the subfamily Pyramidellinae of the family Pyramidellidae, the pyrams and their allies. ''Pyramidella'' is the type genus of the family Pyramidellidae. Nomenclature The generic name ''Pyramidella'' Lamarck, 1799, has been validated under the Plenary Powers of the ICZN , Opinion 386 (1955). The name ''Obeliscus'' Anonymus, 1797 Obeliscus.html" ;"title=" ''Obeliscus"> ''Obeliscus'' Gray, 1847has also been used for this genus, whereas the name ''Pyramidella'' was used for the genus now known as ''Otopleura'' Fischer, 1885. General description The shell has an elongate-conic shape, slightly striated. The many Whorl (mollusc), whorls of the teleoconch are usually inflated and regularly increasing. They are longitudinally ribbed or smooth. The semioval Aperture (mollusc), aperture is entire, widened at its base and rounded in front. .The columella has one to three folds. The sharp outer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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