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Streptoneura
Prosobranchia was a large taxonomic subclass of sea snails, land snails and freshwater snails. This taxon of gastropods dates back to the 1920s. It has however been proven to be polyphyletic (consisting of more than one lineage of descent). Generally speaking in biology taxonomy is required to reflect phylogeny, in other words the classification of a group must reflect its evolutionary descent, as far as that is known, so the taxon Prosobranchia is no longer considered suitable to be used. One can still encounter this subclass used as if it is still valid in many texts and websites. Although Prosobranchia is no longer generally accepted as a taxon by people who study living Mollusca, still the term prosobranch is legitimately used as an anatomically descriptive adjective or noun, and the taxon Prosobranchia is still sometimes used by paleontologists. ''Prosobranch'' means ''gills in front'' (of the heart). In contrast ''opisthobranch'' means ''gills behind'' (and to the right o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prosobranchia
Prosobranchia was a large taxonomic subclass of sea snails, land snails and freshwater snails. This taxon of gastropods dates back to the 1920s. It has however been proven to be polyphyletic (consisting of more than one lineage of descent). Generally speaking in biology taxonomy is required to reflect phylogeny, in other words the classification of a group must reflect its evolutionary descent, as far as that is known, so the taxon Prosobranchia is no longer considered suitable to be used. One can still encounter this subclass used as if it is still valid in many texts and websites. Although Prosobranchia is no longer generally accepted as a taxon by people who study living Mollusca, still the term prosobranch is legitimately used as an anatomically descriptive adjective or noun, and the taxon Prosobranchia is still sometimes used by paleontologists. ''Prosobranch'' means ''gills in front'' (of the heart). In contrast ''opisthobranch'' means ''gills behind'' (and to the right of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protobranchia
Protobranchia is a subclass of bivalve molluscs. It contains the extant orders Nuculanida, Nuculida, and Solemyida. These are deep water clams of a small and primitive order with a taxodont hinge (composed of many similar, small teeth), generally with a central ligament pit, large labial palps which are used in deposit feeding and the gills used only for respiration, the anterior and posterior adductor muscles are nearly equal in size, a foot which is divided sagittally and longitudinally with papillate margins. The foot in Protobranchia clams is without a true byssus gland, although they frequently have a nonhomologous byssal gland in the heel. The byssal gland in these clams does not produce threads as in Pteriomorphia. 2010 Taxonomy In 2010 a new proposed classification system for the Bivalvia was published in by Bieler, Carter & Coan revising the classification of the Bivalvia, including the subclass Protobranchia. Subclass: Protobranchia Order: Nuculanida *Superfa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cowry
Cowrie or cowry () is the common name for a group of small to large sea snails, ocean, marine Gastropoda, gastropod Mollusca, mollusks in the family Cypraeidae, the cowries. The term ''porcelain'' derives from the old Italian language, Italian term for the cowrie shell (''porcellana'') due to their similar appearance. Shells of certain species have historically been used as currency in several parts of the world, as well as being used, in the past and present, very extensively in jewelry, and for other decorative and ceremonial purposes. The cowrie was the shell most widely used worldwide as shell money. It is most abundant in the Indian Ocean, and was collected in the Maldive Islands, in Sri Lanka, along the Indian Malabar coast, in Borneo and on other East Indian islands, in Maluku Islands, Maluku in the Pacific, and in various parts of the African coast from Ras Hafun to Mozambique. Cowrie shell money was important in the trade networks of Africa, South Asia, and East Asia. ... [...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] |
Dorsum (biology)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axis, anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of 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 about such structures as the operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate tests of often more or less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous, as are calcareous sponges ( Porifera), that have spicules which are made of calcium carbonate. In botany ''Calcareous grassland'' is a form of grassland characteristic of soils containing much calcium carbonate from underlying chalk or limestone rock. In medicine The term is used in pathology, for example i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corneous
Corneous is a biological and medical term meaning horny, in other words made out of a substance similar to that of horns and hooves in some mammals. The word is generally used to describe natural or pathological anatomical structures made out of a hard layer of protein. In mammals this protein would usually be keratin. The word corneous is also often used to describe the operculum of a snail, a gastropod mollusc. Not all gastropods have opercula, but in the great majority of those that do have one, the operculum is corneous. (However in several genera within a few families including the marine Naticidae and the terrestrial Pomatiidae, the operculum is primarily calcareous, in other words mostly made of calcium carbonate.) Corneous opercula are made out of the protein conchiolin. References Corneousat dictionary.com Dictionary.com is an online dictionary whose domain was first registered on May 14, 1995. The primary content on Dictionary.com is a proprietary dictionary bas ... [...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] |
Naturalis Biodiversity Center - RMNH
Naturalis Biodiversity Center ( nl, Nederlands Centrum voor Biodiversiteit Naturalis) is a national museum of natural history and a research center on biodiversity in Leiden, Netherlands. It was named the European Museum of the Year 2021. Although its current name and organization are relatively recent, the history of Naturalis can be traced back to the early 1800s. Its collection includes approximately 42 million specimens, making it one of the largest natural history collections in the world. History The beginnings of Naturalis go back to the creation of the Rijksmuseum van Natuurlijke Historie (abbreviated RMNH, National Museum of Natural History) by Dutch King William I on August 9, 1820. In 1878, the geological and mineralogical collections of the museum were split off into a separate museum, remaining distinct until the merger of the Rijksmuseum van Natuurlijke Historie with the Rijksmuseum van Geologie en Mineralogie (abbreviated RGM) in 1984, to form the Nationaal Natu ... [...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] |
Whelk
Whelk (also known as scungilli) is a common name applied to various kinds of sea snail. Although a number of whelks are relatively large and are in the family Buccinidae (the true whelks), the word ''whelk'' is also applied to some other marine gastropod species within several families of sea snails that are not very closely related. Many have historically been used, or are still used, by humans and other animals as food. In a reference serving of whelk, there are of food energy, 24 g of protein, 0.34 g of fat, and 8 g of carbohydrates. Dogwinkles, a predatory species, were used in antiquity to make a rich red dye that improves in color as it ages. True whelks are carnivorous, and feed on annelids, crustaceans, mussels and other molluscs, drilling holes through shells to gain access to the soft tissues. Whelks use chemoreceptors to locate their prey. Usage The common name "whelk" is also spelled ''welk'' or even ''wilk''. The species, genera and families re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volutidae
''Volutidae'', common name volutes, are a taxonomic family of predatory sea snails that range in size from 9 mm to over 500 mm. They are marine gastropod mollusks. Most of the species have no operculum. Distribution This family of sea snails are found mainly in tropical seas, though some species also inhabit the waters of the polar circles. Shell description The shell of species such as ''Melo amphora'' can grow as large as 50 cm (19.7 inches) in length.Poutiers, J. M. (1998). Gastropods in: FAO Species Identification Guide for Fishery Purposes: The living marine resources of the Western Central Pacific Volume 1. Seaweeds, corals, bivalves and gastropods. Rome, FAO, 1998. page 597. Volutes are distinguished by their distinctively marked spiral shells (to which the family name refers, ''voluta'' meaning "scroll" in Latin). The shells have an elongated aperture in their first whorl and an inner lip characterised by a number of deep plaits. The elaborate decorations of the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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