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Nassarius Speciosus
''Nassarius speciosus'', common name the purple-lipped dogwhelk or the splendid nassa, is a species of sea snail, a marine gastropod mollusc in the family Nassariidae, the nassa mud snails or dog whelks. Description The length of the shell varies between 20 mm and 35 mm. The shell is small and robust, featuring strong, widely spaced axial ribs crossed by finer, closely spaced spiral cords. The whorls are shouldered, with the ribs creating nodules along the shoulder. On the latter part of the body whorl, the ribs become weaker. The aperture has a distinct siphonal notch, and the inner lip shows a well-developed callus that extends over both the columella and parietal region. The outer lip has a subterminal external thickening and low internal ridges. The shell is whitish to buff, with paler axial ribs. The aperture and callus are white, while the siphonal notch is a dark purplish-brown when fresh. The surface of a living shell is often covered by a khaki-brown, perios ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Adams (zoologist)
Arthur Adams (1820 in Gosport, Hampshire – 1878) was an England, English physician and natural history, naturalist. Adams was assistant surgeon Royal Navy on board HMS Samarang (1822), HMS ''Samarang'' during the survey of the islands of the East Indian Archipelago, Eastern Archipelago, from 1843 to 1846. He edited the ''Zoology of the voyage of H.M.S. Samarang'' (1850). Adam White (zoologist), Adam White collaborated with him in the descriptions of the Crustacean, Crustacea from the voyage. In 1857, during the Second Opium War, Second China War whilst serving as Surgeon on HMS Actaeon (1831), HMS ''Actaeon'', he was present at the storming of Guangzhou, Canton and awarded the Second China War Medal, China War Medal. He retired as Staff Surgeon aboard flagship HMS Royal Adelaide (1828), HMS ''Royal Adelaide'' at Plymouth in 1870. He was a prolific malacology, malacologist who described "hundreds of new species, most of them unillustrated and insufficiently diagnosed". He ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nassarius
''Nassarius'', common name nassa mud snails (USA) or dog whelks (UK), is a genus of minute to medium-sized sea snails, marine gastropod molluscs in the family Nassariidae.Bouchet, P.; Gofas, S. (2010). Nassarius Duméril, 1806. In: Bouchet, P.; Gofas, S.; Rosenberg, G. (2010) World Marine Mollusca database. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138235 on 2010-11-30 They are scavengers. Etymology The name is derived from the Latin word "nassa", meaning a wickerbasket with a narrow neck, for catching fish. ''Nassarius'' would then mean "someone who uses such a wickerbasket for catching fish". Ecology Distribution and habitat Species within this genus are found worldwide. These snails usually live on mud flats or sand flats, intertidally or subtidally. Life habits Most ''Nassarius'' species are very active scavengers, feeding on crabs and carrion as dead fish, etc. They often burrow into marine substrates a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transkei
Transkei ( , meaning ''the area beyond Great Kei River, [the river] Kei''), officially the Republic of Transkei (), was an list of historical unrecognized states and dependencies, unrecognised state in the southeastern region of South Africa from 1976 to 1994. It was, along with Ciskei, a Bantustan for the Xhosa people, and operated as a nominally independent parliamentary democracy. Its capital was Mthatha, Umtata (renamed Mthatha in 2004). Transkei represented a significant precedent and historic turning point in South Africa's policy of apartheid and "separate development"; it was the first of four territories to be declared independence, independent of South Africa. Throughout its existence, it remained an internationally unrecognised, diplomatically isolated, politically unstable ''de facto'' one-party state, which at one point broke relations with South Africa, the only country that acknowledged it as a legal entity. In 1994, it was reintegrated into its larger neighbour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namibia
Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the northeast, approximating a quadripoint, Zimbabwe lies less than 200 metres (660 feet) away along the Zambezi, Zambezi River near Kazungula, Zambia. Namibia's capital and largest city is Windhoek. Namibia is the driest country in sub-Saharan Africa, and has been inhabited since prehistoric times by the Khoekhoe, Khoi, San people, San, Damara people, Damara and Nama people. Around the 14th century, immigration, immigrating Bantu peoples arrived as part of the Bantu expansion. From 1600 the Ovambo people#History, Ovambo formed kingdoms, such as Ondonga and Oukwanyama. In 1884, the German Empire established rule over most of the territory, forming a colony known as German South West Africa. Between 1904 and 1908, German troops waged a punitive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agulhas Bank Complex Marine Protected Area
The Agulhas Bank Complex Marine Protected Area is an offshore marine protected area on the continental shelf lying approximately 39 nautical miles southeast of Cape Agulhas off the Western Cape in the Exclusive Economic Zone of South Africa. History The MPA was proclaimed by the Minister of Environmental Affairs, in terms of sections 48A(2) and 86(1)(a), (b), (c) and (d) of the National Environmental Management: Protected Areas Act, 57 of 2003. Purpose A marine protected area (MPA) is defined by the IUCN as "A clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values". The Agulhas banks have supported economically important fisheries for more than a century. This MPA is intended to protect spawning aggregations of several economically important fish, including the endangered Red steenbras, the largest seabream, a long liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
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 b ... [...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 (mollusc), 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 (mollusc), aperture of the shell. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Callus (mollusc)
A callus is an anatomical feature that exists in some mollusk shells, a thickened area of shell material that can partly or completely cover the umbilicus, or can be located as a coating on the body whorl near the aperture of the shell (i.e. a parietal callus or columellar callus). It is a hardened deposit of enamel, which varies in coloration and size depending on the species A funiculus (plural: funiculi) is a narrow ridge of callus spiraling from the upper lip into the umbilicus. A callus exists in the shells of various species of gastropods (snails) and also in the shells of several species of ''Nautilus'', a cephalopod. A callum is an anatomical feature of some mature bivalve shells of species in the family Pholadidae Pholadidae, known as piddocks or angelwings, are a family (biology), family of bivalve molluscs similar to a clam. Background Piddocks are unique in that each side of their shells is divided into 2 or 3 separate sections. Furthermore, one of the ..., ... [...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 (mollusc), 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 ... [...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] |
Common Name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrasted with the scientific name for the same organism, which is often based in Latin. A common name is sometimes frequently used, but that is not always the case. In chemistry, IUPAC defines a common name as one that, although it unambiguously defines a chemical, does not follow the current systematic naming convention, such as acetone, systematically 2-propanone, while a vernacular name describes one used in a lab, trade or industry that does not unambiguously describe a single chemical, such as copper sulfate, which may refer to either copper(I) sulfate or copper(II) sulfate. Sometimes common names are created by authorities on one particular subject, in an attempt to make it possible for members of the general public (including s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
