|
Euspira Heros
''Euspira heros'', the northern moon snail, is a species of large sea snail in the family Naticidae.Gofas, S.; Bouchet, P.; Rosenberg, G. (2015). Euspira heros (Say, 1822). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=160315 on 2015-06-21 This large snail is rather uncommon intertidally, but is much more common subtidally. This species, like all moon snails, feeds voraciously on clams and other snails. Description The shell of this species is globular and can, under the right conditions, grow up to long. The operculum is large, ear-shaped in outline, and is corneous and somewhat transparent. On beaches where the shell of this species washed up commonly, the operculum will usually also be found washed up in the drift line. Distribution The distribution of ''Euspira heros'' falls within the range: 51.5°N to 33°N; 76°W to 65°W. This western Atlantic species occurs in: * Canada: Labrador, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Say
Thomas Say (June 27, 1787 – October 10, 1834) was an American entomologist, conchologist, and Herpetology, herpetologist. His studies of insects and shells, numerous contributions to scientific journals, and scientific expeditions to Florida, Georgia, the Rocky Mountains, Mexico, and elsewhere made him an internationally known naturalist. Say has been called the father of American descriptive entomology and American conchology. He served as librarian for the Academy of Natural Sciences of Philadelphia, curator at the American Philosophical Society (elected in 1817), and professor of natural history at the University of Pennsylvania. Early life and education Born in Philadelphia into a prominent Religious Society of Friends, Quaker family, Thomas Say was the great-grandson of John Bartram, and the great-nephew of William Bartram. His father, Dr. Benjamin Say, was brother-in-law to another Bartram son, Moses Bartram. The Say family had a house, "The Cliffs" at Gray's Ferry Bridge, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neverita Lewisii
''Neverita lewisii'' (previously known as ''Polinices lewisii'', ''Lunatia lewisii'', ''Euspira lewisii''), common name Lewis's moon snail, is a species of large operculated sea snail. It is a predatory marine gastropod in the family Naticidae, the moon snails.Bouchet, P. (2012). Lunatia lewisii (Gould, 1847). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=584785 on 2012-08-16 Traditionally, this species was assigned to either the genus '' Lunatia'', the genus ''Polinices'' or the genus ''Euspira''. Recently, it was assigned to the genus ''Neverita'' based on molecular data.Huelsken, T., Tapken, D., Dahlmann, T., Wägele, H., Riginos, C., Hollmann, M. (2012). Systematics and phylogenetic species delimitation within Polinices s.l. (Caenogastropoda: Naticidae) based on molecular data and shell morphology. Organisms Diversity & Evolution. DOI10.1007/s13127-012-0111-5 This is the largest species in the family. Distributio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radula
The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the molluscs, and is found in every class of mollusc except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs. The arrangement of teeth ( denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other molluscs. Other predatory marine snails ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Countersink
A countersink (symbol: ⌵) is a conical hole cut into a manufactured object, or the cutter used to cut such a hole. A common use is to allow the head of a countersunk bolt, screw or rivet, when placed in the hole, to sit flush with or below the surface of the surrounding material (by comparison, a counterbore makes a flat-bottomed hole that might be used with a socket-head capscrew). A countersink may also be used to remove the burr left from a drilling or tapping operation thereby improving the finish of the product and removing any hazardous sharp edges. The basic geometry of a countersink (cutter) inherently can be applied to the plunging applications described above (axial feed only) and also to other milling applications (sideways traversal). Therefore, countersinks overlap in form, function, and sometimes name with chamfering endmills (endmills with angled tips). Regardless of the name given to the cutter, the surface being generated may be a conical chamfer (plunging ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bays, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infralittoral
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas that are permanently submerged — known as the ''foreshore'' — and the terms are often used interchangeably. However, the geographical meaning of ''littoral zone'' extends well beyond the intertidal zone to include all neritic waters within the bounds of continental shelves. Etymology The word ''littoral'' may be used both as a noun and as an adjective. It derives from the Latin noun ''litus, litoris'', meaning "shore". (The doubled ''t'' is a late-medieval innovation, and the word is sometimes seen in the more classical-looking spelling ''litoral''.) Description The term has no single definition. What is regarded as the full extent of the littoral zone, and the way the littoral zone is divided into subregions, varies in different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the Atlanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basionym
In the scientific name of organisms, basionym or basyonym means the original name on which a new name is based; the author citation of the new name should include the authors of the basionym in parentheses. The term "basionym" is used in both botany and zoology. In zoology, alternate terms such as original combination or protonym are sometimes used instead. Bacteriology uses a similar term, basonym, spelled without an ''i''. Although "basionym" and "protonym" are often used interchangeably, they have slightly different technical definitions. A basionym is the ''correct'' spelling of the original name (according to the applicable nomenclature rules), while a protonym is the ''original'' spelling of the original name. These are typically the same, but in rare cases may differ. Use in botany The term "basionym" is used in botany only for the circumstances where a previous name exists with a useful description, and the '' International Code of Nomenclature for algae, fungi, and plants' ... [...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] |
Subtidal
The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated environment for marine life, from plankton up to large fish and corals, while physical oceanography sees it as where the oceanic system interacts with the coast. Definition (marine biology), context, extra terminology In marine biology, the neritic zone, also called coastal waters, the coastal ocean or the sublittoral zone, refers to that zone of the ocean where sunlight reaches the ocean floor, that is, where the water is never so deep as to take it out of the photic zone. It extends from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 meters (660 feet). Above the neritic zone lie the intertidal (or eulittoral) and supralittoral zones; below it the continental slope begi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_torquata_002.jpg "Click for more on -> Operculum (gastropod)")
