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Daphnella Grundifera
''Daphnella grundifera'' is a species of sea snail, a marine gastropod mollusk in the family Raphitomidae. Description The length of the shell attains 5.2 mm, its diameter 3.3 mm. (Original description) The small, biconic, white shell has a brown rounded sinusigera protoconch consisting of three whorls, followed by three subsequent whorls. The suture is appressed, minutely crenulated by the ends of the axial sculpture in front of it. The anal sulcus is wide and only moderately deep. The fasciole is wide, sculptured with retractively arcuate, sharp, elevated lines. The other axial sculpture consists of well-marked incremental lines, and faint narrow indications of obsolete ribbing. The spiral sculpture consists of a single strong peripheral keel, about eight slender low threads with wider interspaces in front of it, minutely crenulate by the axial sculpture, and much closer fine threading on the siphonal canal. The base is moderately rounded. The columella is straight and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Healey Dall
William Healey Dall (August 21, 1845 – March 27, 1927) was an American naturalist, a prominent malacologist, and one of the earliest scientific explorers of interior Alaska. He described many mollusks of the Pacific Northwest of America, and was for many years America's preeminent authority on living and fossil mollusks. Dall also made substantial contributions to ornithology, zoology, physical and cultural anthropology, oceanography and paleontology. In addition he carried out meteorological observations in Alaska for the Smithsonian Institution. Biography Early life Dall was born in Boston, Massachusetts. His father Charles Henry Appleton Dall, (1816–86), a Unitarian minister, moved in 1855 to India as a missionary. His family however stayed in Massachusetts, where Dall's mother Caroline Wells Healey was a teacher, transcendentalist, reformer, and pioneer feminist. In 1862, Dall's father, on one of his few brief visits home, brought his son in contact with some natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sculpture (mollusc)
Sculpture is a feature of many of the shells of mollusks. It is three-dimensional ornamentation on the outer surface of the shell, as distinct from either the basic shape of the shell itself or the pattern of colouration, if any. Sculpture is a feature found in the shells of gastropods, bivalves, and scaphopods. The word "sculpture" is also applied to surface features of the aptychus of ammonites, and to the outer surface of some calcareous opercula of marine gastropods such as some species in the family Trochidae. Sculpture can be concave or convex, incised into the surface or raised from it. Sometimes the sculpture has microscopic detailing. The term "sculpture" refers only to the calcareous outer layer of shell, and does not include the proteinaceous periostracum, which is in some cases textured even when the underlying shell surface is smooth. In many taxa, there is no sculpture on the shell surface at all, apart from the presence of fine growth lines. The sculpture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnella
''Daphnella'' is a genus of sea snails, marine gastropod mollusks in the family Raphitomidae. Not to be confused with ''Daphnella'' Baird, 1850, a synonym of ''Diaphanosoma'' Fischer, 1850 belonging to the Sididae, a family of ctenopods. Description This genus is well characterised by a small, thin shell, elongate-ovate form, a sharp outer lip, the position of the sinus on the line of the advancing suture, and by the reduction of the siphonal canal. The protoconch has a sinusigerid (or diagonally cancellate) structure. The surface is usually striated. The spire is elevated, the body whorl is elongated. The early whorls of the teleoconch show a nodulous sculpture produced by strong axial riblets and strong spiral lirations. These axial riblets disappear on the body whorl, while the spiral lirations remain. The aperture is oblong-oval, slightly channelled in front. The columella is simple. The outer lip is slightly thickened in the adult. Species Species within the genus ''Daphne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuba
Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbean Sea, Gulf of Mexico, and Atlantic Ocean meet. Cuba is located east of the Yucatán Peninsula (Mexico), south of both the American state of Florida and the Bahamas, west of Hispaniola ( Haiti/Dominican Republic), and north of both Jamaica and the Cayman Islands. Havana is the largest city and capital; other major cities include Santiago de Cuba and Camagüey. The official area of the Republic of Cuba is (without the territorial waters) but a total of 350,730 km² (135,418 sq mi) including the exclusive economic zone. Cuba is the second-most populous country in the Caribbean after Haiti, with over 11 million inhabitants. The territory that is now Cuba was inhabited by the Ciboney people from the 4th millennium BC with the Gua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guadeloupe
Guadeloupe (; ; gcf, label=Antillean Creole, Gwadloup, ) is an archipelago and overseas department and region of France in the Caribbean. It consists of six inhabited islands—Basse-Terre, Grande-Terre, Marie-Galante, La Désirade, and the two inhabited Îles des Saintes—as well as many uninhabited islands and outcroppings. It is south of Antigua and Barbuda and Montserrat, north of the Commonwealth of Dominica. The region's capital city is Basse-Terre, located on the southern west coast of Basse-Terre Island; however, the most populous city is Les Abymes and the main centre of business is neighbouring Pointe-à-Pitre, both located on Grande-Terre Island. It had a population of 384,239 in 2019.Populations légales 2019: 971 Guadeloupe INSEE Like the other overseas departments, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgia (U
Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the country in the Caucasus ** Kingdom of Georgia, a medieval kingdom ** Georgia within the Russian Empire ** Democratic Republic of Georgia, established following the Russian Revolution ** Georgian Soviet Socialist Republic, a constituent of the Soviet Union * Related to the US state ** Province of Georgia, one of the thirteen American colonies established by Great Britain in what became the United States ** Georgia in the American Civil War, the State of Georgia within the Confederate States of America. Other places * 359 Georgia, an asteroid * New Georgia, Solomon Islands * South Georgia and the South Sandwich Islands Canada * Georgia Street, in Vancouver, British Columbia, Canada * Strait of Georgia, British Columbia, Canada United K ... [...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] |
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, prominent ... [...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] |
Anal Sulcus
The anal sulcus, also called the anal sinus or anal canal, in Gastropods is a notch, a shelly tube at the top of the aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt .... It is the first notch close to the suture. It houses the anal siphon through which the snail expels water and waste products. The anal sulcus can be described, according to the species, as well-defined, weakly defined, shallow, sharp, wide, narrow or inverted U-shaped. In some species, such as in the Murex family, the anal sulcus is absent. The anal sulcus can be linked on the edges to a fasciole, a spiral band on the shell, formed by successive growth lines. It can also have a subsutural callus (such as in Clathrodrillia callianira). References Gastropod anatomy Mollusc shells {{gastropod-stub ... [...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] |
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