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Parietal Callus
A parietal callus is a feature of the shell anatomy of some groups of snails, i.e. gastropods. It is a thickened calcareous deposit which may be present on the parietal wall of the aperture of the adult shell. The parietal wall is the margin of the aperture and part of the wall of the body whorl that is closest to the columella. The callus is often smooth and glossy, but can also be decorated with raised ribs or wrinkles. This feature is found in such marine families as Ranellidae (pictured), Cassidae, Nassariidae, Ringiculidae and others. It is also found in some families of land snails, terrestrial pulmonates. The callus is often "glazed", to help the animal slide in and out of the shell more easily. When the callus covers of 50% of the surface area of the ventral part of the shell, it is called an "extreme parietal callus". See also * Gastropod shell * Aperture (mollusc) The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the she ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Semicassis Pyrum (base)
''Semicassis pyrum'', common name the "pear bonnet" or "common helmet", is a species of large sea snail, a marine gastropod mollusc in the family Cassidae The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonnet snails. These are marine gastropod mollusks in the superfamily Tonnoidea and the clade Littorinimorpha.Gofas ..., the helmet shells, bonnet shells and their allies. References * Powell A. W. B., William Collins Publishers Ltd, Auckland 1979 * Cassidae Taxa named by Jean-Baptiste Lamarck Gastropods described in 1822 {{Cassidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cymatium Pileare
Cymatium (from Greek κυμάτιον "small wave"), the uppermost molding at the top of the cornice in the classical order, is made of the s-shaped cyma molding (either ''cyma recta'' or ''cyma reversa''), combining a concave cavetto with a convex ovolo. It is characteristic of Ionic columns and can appear as part of the entablature, the epistyle or architrave, which is the lintel or beam that rests on the capitals of columns, and the capital itself. Often the cymatium is decorated with a palmette or egg-and-dart ornament on the surface of the molding. The heights of the parts of the capital are to be so regulated that three of the nine parts and a half, into which it was divided, lie below the level of the astragal on the top of the shaft. The remaining parts are for the cymatium, abacus, and channel. The projection of the cymatium beyond the abacus is not to be greater than the size of the diameter of the eye f the voluteIn the case of a concave-convex profile, a distinction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gastropod Shell
The gastropod shell is part of the body of many gastropods, including snails, 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, ostracum, is typically made of calcium carbonate (CaCO3) precipitated into an organic matrix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Snail
A snail is a shelled gastropod. The name is most often applied to land snails, terrestrial molluscs, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastropoda that have a coiled gastropod shell, shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also numerous species of sea snails and freshwater snails. Gastropods that naturally lack a shell, or have only an internal shell, are mostly called ''slugs'', and land snails that have only a very small shell (that they cannot retract into) are often called ''semi-slugs''. Snails have considerable human relevance, including Snails as food, as food items, as pests, and as vectors of disease, and their shells are used as decorative objects and are incorporated into jewellery. The snail has also had some cultural significance, tending t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Gastropod
Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and from the land. There are many thousands of species of sea snails and sea slug, slugs, as well as freshwater snails, freshwater limpets, land snails and slugs. The class Gastropoda is a diverse and highly successful class of mollusks within the phylum Mollusca. It contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Furongian, Late Cambrian. , 721 family (taxonomy), families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently neontology, extant living fossil, with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcareous'' is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically in relation to such structures as the operculum (gastropod), operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate Test (biology), tests of, often, more-or-less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous organisms, as are the Calcarea, calcareous sponges (Calcarea), that have spicules which are made of calcium carbonate. Additionally, reef-building corals, or Scleractinia, are calcareous organisms that form their rigid skeletal structure th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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] [Amazon] |
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] [Amazon] |
Ranellidae
The Ranellidae, common name the triton shells or tritons, are a taxonomic family of small to very large predatory sea snails, marine gastropod mollusks in the order Littorinimorpha. Distribution The Tritons are principally equatorial in their geographical distribution, and belong more especially to the Asiatic fauna. Those with the siphonal canal very much produced are obtained from deep water. The cancellated forms are from sand, in deep water; and those covered with an epidermis are chiefly from sandy mud, in from six to thirty fathoms. Subfamilies According to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, the family Ranellidae consisted of two subfamilies: *Ranellinae Gray, 1854 - synonyms: Agrobuccininae Kilias, 1973; Simpulidae Dautzenberg, 1900; Gyrineinae Higo & Goto, 1993 (n.a.) *Cymatiinae Iredale, 1913 (1854) - synonyms: Tritoniidae H. Adams & A. Adams, 1853 (inv.); Neptunellinae Gray, 1854; Lampusiidae Newton, 1891; Lotoriidae Harris, 1897; Septidae D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cassidae
The Cassidae are a taxonomic family of medium-sized, large, and sometimes very large sea snails commonly called helmet snails or bonnet snails. These are marine gastropod mollusks in the superfamily Tonnoidea and the clade Littorinimorpha.Gofas, S. (2010). Cassidae. 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=22999 on 2011-01-19 About 60 species comprise the family Cassidae; an example is '' Cypraecassis rufa''. Nomenclature Despite its incorrect formation (the correct one would be Cassididae, based on the genitive form of Cassis), the ICZN has placed the name Cassidae Latreille, 1825 on the official list of family names, therefore avoiding homonymy with Cassididae Stephens, 1831 (based on Cassida Linnaeus, 1758, a chrysomelid beetle); Opinion 1023 (1974, Bulletin of Zoological Nomenclature 31: 127–129). Distribution Species of thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Nassariidae
The Nassariidae, Nassa mud snails (US), or dog whelks (UK) are a taxonomic family of small to medium-sized snails, mostly marine gastropod mollusks in the clade Neogastropoda. These snails have rounded shells with a high spire, an oval aperture, and a siphonal notch. This family of snails is found worldwide. These snails are found mostly in shallow water, on sandy or muddy substrates, often intertidally, but sometimes in deep water. They can be present in very large numbers in suitable habitat. Nassariidae are primarily active and lively scavengers. Subtaxa , the World Register of Marine Species accepts the following 48 genera, arranged within 7 subfamilies. Anentominae E. E. Strong, Galindo & Kantor, 2017 * '' Anentome'' Cossmann, 1901 * ''Clea Clea is a female given name. Clea may refer to: People with the given name * Clea DuVall (born 1977), actress * Clea Hoyte (born 1981), West Indies cricketer * Clea Koff (born 1972), British-born American forensic ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ringiculidae
Ringiculidae are a family (biology), family of small deep water sea snails, marine (ocean), marine gastropod mollusks or micromollusks in the informal group Lower Heterobranchia.Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International Journal of Malacology, 47(1-2). ConchBooks: Hackenheim, Germany. . . 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278 Ringiculidae is the only family within the superfamily Ringiculoidea. The shells of species in this family superficially resemble minute versions of the shells of the Cassinae. Genera Genera in the family Ringiculidae include:Arthur William Baden Powell, Powell A. W. B., ''New Zealand Mollusca'', HarperCollins, William Collins Publishers Ltd, Auckland, New Zealand 1979 * Genus † ''Avellana (gastropod), Avellana'' d'Orbigny, 1842 * Genus ''Microglyphis'' W. H. Dall, Dall, 1902 * Genus ''Pseudori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
