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Uvanilla Olivacea
''Uvanilla olivacea'', common name the blood-spotted star shell, is a species of sea snail, a marine gastropod mollusk in the family Turbinidae, the turban snails. Distribution This species is found from La Paz in the Gulf of California southwards to Oaxaca, in Mexico.Keen M. (1971). Sea shells of Tropical West America. Marine mollusks from Baja California to Perú. (2nd edit.). Stanford University Press pp. 1064, at p. 356. Description The shell is greenish brown and roughly an equilateral triangle in profile with a slightly wavy thickened edge on the bottom of the whorl and sculpture consisting of fine diagonal spiral ridges. The single most striking feature is a brilliant spot of reddish-orange at the base of the umbilical pit which is bordered by a dark brown to black outer edge. Average height is 55 mm, and average diameter is 65 mm. The acute, imperforate shell has a conic shape. Its color pattern is olive-green or brownish. The 6–7 whorls are slightly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod Shell
The gastropod shell is part of the body of a Gastropoda, 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 (mollusc), 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 (mollusc), mantle. The calcareous central layer, tracum, is typically made of calcium carbonate precipitated into an organic matrix known as c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilicus (mollusc)
The umbilicus of a shell is the axially aligned, hollow cone-shaped space within the whorls of a coiled mollusc shell. The term umbilicus is often used in descriptions of gastropod shells, i.e. it is a feature present on the ventral (or under) side of many (but not all) snail shells, including some species of sea snails, land snails, and freshwater snails. The word is also applied to the depressed central area on the planispiral coiled shells of ''Nautilus'' species and fossil ammonites. (These are not gastropods, but shelled cephalopods.) In gastropods The spirally coiled whorls of gastropod shells frequently connect to each other by their inner sides, during the natural course of its formation. This results in a more or less solid central axial pillar, known as the columella. The more intimate the contact between the concave side of the whorls is, the more solid the columella becomes. On the other hand, if this connection is less intense, a hollow space inside the whorls may re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uvanilla
''Uvanilla'' is a genus of sea snails, marine gastropod mollusks in the family Turbinidae Turbinidae, the turban snails, are a family of small to large marine gastropod molluscs in the superfamily Trochoidea.Bouchet, P. (2014). Turbinidae Rafinesque, 1815. Accessed through: World Register of Marine Species at http://www.marinespecies ..., the turban snails. Species Species within the genus ''Uvanilla'' include: * '' Uvanilla babelis'' (P. Fischer, 1874) * '' Uvanilla buschii'' (Philippi, 1844) * '' Uvanilla olivacea'' (W. Wood, 1828) * '' Uvanilla unguis'' (W. Wood, 1828) ;Species brought into synonymy: * ''Uvanilla heimburgi'' Dunker, 1882: synonym of '' Astralium heimburgi'' (Dunker, 1882) References * Keen M. (1971) ''Sea shells of tropical West America. Marine mollusks from Baja California to Perú'', ed. 2. Stanford University Press. 1064 pp. * Alf A. & Kreipl K. (2011) ''The family Turbinidae. Subfamilies Turbininae Rafinesque, 1815 and Prisogasterinae Hickman & M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intertidal
The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of Marine habitat, habitats with various species of Marine life, life, such as seastars, Sea urchin, sea urchins, and many species of coral with regional differences in biodiversity. Sometimes it is referred to as the ''littoral zone'' or ''shore, seashore'', although those can be defined as a wider region. The well-known area also includes steep rocky Cliff, cliffs, sandy Beach, beaches, Bog, bogs or wetlands (e.g., vast Mudflat, mudflats). The area can be a narrow strip, as in Pacific island, Pacific islands that have only a narrow tidal range, or can include many meters of shoreline where shallow beach slopes interact with high tidal excursion. The peritidal zone is similar but somewhat wider, extending from above the highest tide level to below the lowest. Organisms in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilicus (mollusc)
The umbilicus of a shell is the axially aligned, hollow cone-shaped space within the whorls of a coiled mollusc shell. The term umbilicus is often used in descriptions of gastropod shells, i.e. it is a feature present on the ventral (or under) side of many (but not all) snail shells, including some species of sea snails, land snails, and freshwater snails. The word is also applied to the depressed central area on the planispiral coiled shells of ''Nautilus'' species and fossil ammonites. (These are not gastropods, but shelled cephalopods.) In gastropods The spirally coiled whorls of gastropod shells frequently connect to each other by their inner sides, during the natural course of its formation. This results in a more or less solid central axial pillar, known as the columella. The more intimate the contact between the concave side of the whorls is, the more solid the columella becomes. On the other hand, if this connection is less intense, a hollow space inside the whorls may re ... [...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] |
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] |
Suture (anatomy)
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperforate
For postage stamps, separation is the means by which individual stamps are made easily detachable from each other. Methods of separation include: # perforation: cutting rows and columns of small holes # rouletting: small horizontal and vertical cuts # diecutting: cut paper to shape using a metal die—used for self-adhesive stamps. Early years In the early years, from 1840 until 1850, all stamps were issued imperforate, and had to be cut from the sheet with scissors or knife. This was time-consuming and error-prone (as mangled stamps of the era attest). Once reliable separation equipment became available, nations switched rapidly. Imperforate stamps have been issued occasionally since then, either because separation equipment was temporarily unavailable (in newborn nations for instance), to makers of automatic stamp vending equipment (the United States did this in the 1900s and 1910s), as novelties for stamp collectors (particularly when stamps are issued in souvenir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uvanilla Olivacea 001
''Uvanilla'' is a genus of sea snails, marine gastropod mollusks in the family Turbinidae, the turban snails. Species Species within the genus ''Uvanilla'' include: * ''Uvanilla babelis'' (P. Fischer, 1874) * ''Uvanilla buschii'' (Philippi, 1844) * ''Uvanilla olivacea'' (W. Wood, 1828) * ''Uvanilla unguis'' (W. Wood, 1828) ;Species brought into synonymy: * ''Uvanilla heimburgi'' Dunker, 1882: synonym of ''Astralium heimburgi ''Astralium heimburgi'' is a species of sea snail, a marine gastropod mollusk in the family Turbinidae, the turban snails.Bouchet, P. (2012). ''Astralium heimburgi''. Accessed through: World Register of Marine Species at http://www.marinespec ...'' (Dunker, 1882) References * Keen M. (1971) ''Sea shells of tropical West America. Marine mollusks from Baja California to Perú'', ed. 2. Stanford University Press. 1064 pp. * Alf A. & Kreipl K. (2011) ''The family Turbinidae. Subfamilies Turbininae Rafinesque, 1815 and Prisogasterinae Hickman & McLea ... [...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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