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Linckia Columbiae
''Linckia columbiae'' is a species of starfish in the family Ophidiasteridae. It is found in the East Pacific where it ranges from California (USA) to northwest Peru, including offshore islands such as the Galápagos.James, M.J., eds. (1991). ''Galápagos Marine Invertebrates: Taxonomy, Biogeography, and Evolution in Darwin's Islands.'' pp. 349. Topics in Geobiology. Common names include fragile star, Pacific comet sea star and variable sea star. Description ''Linckia columbiae'' can grow to 10 cm (4 in) across and varies greatly in colour and shape and even the number of rays. Writing in 1904, Monks stated, "In over 400 specimens examined not more than four were symmetrical, and no two were alike ... The normal number of rays is five, but some specimens have only one, while others have four, six, seven or even nine." The disc is small with one or two madreporites, usually oval and variable in size. The long cylindrical rays have blunt, triangular points that turn up ... [...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] |
Linckia Guildingi
''Linckia guildingi'', also called the common comet star, Guilding's sea star or the green Linckia, is a species of sea star reported from the shallow waters of the tropical Pacific Ocean, Indian Ocean, Atlantic Ocean and the Caribbean Sea. Taxonomy Recent studies have indicated that ''Linckia guildingi'' may represent several cryptic species. Examination of the mtDNA showed that there are two clades within ''L. guildingi''. The divergence between these implies that they separated over a million years ago. Distribution This species was described from St Vincent's, (Saint Vincent (Antilles)) in the Caribbean Sea. Description ''L. guildingi'' has a small disc and usually 5 (occasionally 4 or 6) long cylindrical arms. The upper surface appears smooth but is in fact rough to the touch with low, firm nodules. Though this starfish is often green, it comes in a range of colours including various shades of brown, blue and dull red. Biology ''L. guildingi'' sometimes exhibits autotomy, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tube Feet
Tube feet (technically podia) are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on brittle stars, and have only a feeding function in feather stars. They are part of the water vascular system. Structure and function Tube feet function in locomotion, feeding, and respiration. The tube feet in a starfish are arranged in grooves along the arms. They operate through hydraulic pressure. They are used to pass food to the oral mouth at the center, and can attach to surfaces. A starfish that is inverted turns one arm over and attaches it to a solid surface, and levers itself the right way up. Tube feet allow these different types of animals to stick to the ocean floor and move slowly. Each tube foot consists of two parts: the ampulla and the podium. The ampulla is a water-filled sac contained in the body of the animal that contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autotomy
Autotomy (from the Greek language, Greek ''auto-'', "self-" and ''tome'', "severing", wikt:αὐτοτομία, αὐτοτομία) or self-amputation, is the behaviour whereby an animal sheds or discards one or more of its own appendages, usually as a self-preservation, self-defense mechanism to elude a predation, predator's grasp or to distract the predator and thereby allow escape. Some animals have the ability to regeneration (biology), regenerate the lost body part later. Autotomy has multiple evolutionary origins and is thought to have evolved at least nine times independently in animalia. The term was coined in 1883 by Léon Fredericq, Leon Fredericq. Vertebrates Reptiles and amphibians Some lizards, salamanders and tuatara when caught by the tail will shed part of it in attempting to escape. In many species the detached tail will continue to wriggle, creating a deceptive sense of continued struggle, and distracting the predator's attention from the fleeing prey animal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocos Island
Cocos Island ( es, Isla del Coco) is an island in the Pacific Ocean administered by Costa Rica, approximately southwest of the Costa Rican mainland. It constitutes the 11th of the 13 districts of Puntarenas Canton of the Province of Puntarenas. With an area of approximately , the island is more or less rectangular in shape. It is the southernmost point of geopolitical North America if non-continental islands are included. The entirety of Cocos Island has been designated a Costa Rican National Park since 1978, and has no permanent inhabitants other than Costa Rican park rangers. Surrounded by deep waters with counter-currents, Cocos Island is admired by scuba divers for its populations of hammerhead sharks, rays, dolphins and other large marine species. The wet climate and oceanic qualities give Cocos an ecological character that is not shared with either the Galápagos Archipelago or any of the other islands (for example, Malpelo, Gorgona or Coiba) in the eastern Pacific O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarion Island
Isla Clarión, formerly called Santa Rosa, is the second largest, westernmost and most remote of Mexico's Revillagigedo Islands. The island is located west of Socorro Island and over from the Mexican mainland. It has an area of and three prominent peaks. The westernmost and tallest peak, ''Monte Gallegos'', is high. The central peak is called ''Monte de la Marina'', , and the eastern peak Pico de la Tienda . The coasts are backed by perpendicular cliffs, high, with the exception of the middle part of the southern coast in the vicinity of ''Bahía Azufre'' (Sulphur Bay), which is the location of a small military garrison with a contingent of 9 soldiers. Two small and at least temporarily brackish pools are the only source of fresh water; even these may dry up in summers with little rain. Clarion can only be reached by sea, which from Mexico takes 30 hours. History No signs to indicate prehistoric human activity have ever been found on Clarión Island. It was visited in l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulf Of California
The Gulf of California ( es, Golfo de California), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Bermejo''), is a marginal sea of the Pacific Ocean that separates the Baja California Peninsula from the Mexico, Mexican mainland. It is bordered by the states of Baja California, Baja California Sur, Sonora, and Sinaloa with a coastline of approximately . Rivers that flow into the Gulf of California include the Colorado River, Colorado, Fuerte River, Fuerte, Mayo River (Mexico), Mayo, Sinaloa River, Sinaloa, Sonora River, Sonora, and the Yaqui River, Yaqui. The surface of the gulf is about . Maximum depths exceed because of the complex geology, linked to plate tectonics. The gulf is thought to be one of the most diverse seas on Earth and is home to more than 5,000 species of micro-invertebrates. Parts of the Gulf of California are a UNESCO World Heritage Site. Geography History The marine expeditions of Fortún ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Pedro Bay (California)
San Pedro Bay is an inlet on the Pacific Ocean coast of southern California, United States. It is the site of the Port of Los Angeles and the Port of Long Beach, which together form the fifth-busiest port facility in the world (behind the ports of Shanghai, Singapore, Hong Kong, and Shenzhen) and the busiest in the Americas. The Los Angeles community of San Pedro borders a small portion of the western side of the bay, and shares the name. The city of Long Beach borders the port on the eastern side of the bay. The northern part of the bay, which is the largest part of the port, is bordered by the Los Angeles neighborhood of Wilmington. Seabed Most of the bay is between deep. The seabed near Long Beach has experienced considerable subsidence as a result of oil extraction in the Wilmington Field from the 1950s onward. This helped the Port of Long Beach surpass the Port of Los Angeles as the leading port in the United States for a time in the 1980s and 1990s, since the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambulacrum (anatomy)
In zoology, an ambulacrum is an elongated area of the shell of an echinoderm in which a row of tube feet are arranged. It is pluralized as ''ambulacra''. The area on the shell between ambulacra is known as an interambulacrum Ambulacral is a term typically used in the context of anatomical parts of the phylum Echinodermata or class Asteroidea and Edrioasteroidea. Echinoderms can have ambulacral parts that include ossicles, plates, spines, and suckers. For example, se .... References Echinoderm anatomy {{echinoderm-anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starfish
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish live on the seabed in all the world's oceans, from warm, tropical zones to frigid, polar regions. They are found from the intertidal zone down to abyssal depths, at below the surface. Starfish are marine invertebrates. They typically have a central disc and usually five arms, though some species have a larger number of arms. The aboral or upper surface may be smooth, granular or spiny, and is covered with overlapping plates. Many species are brightly coloured in various shades of red or orange, while others are blue, grey or brown. Starfish have tube feet operated by a hydraulic system and a mouth at the centre of the oral or lower surface. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madreporite
The madreporite is a light colored calcareous opening used to filter water into the water vascular system of echinoderms. It acts like a pressure-equalizing valve. It is visible as a small red or yellow button-like structure, looking like a small wart, on the aboral surface of the central disk of a sea star or sea urchin or the oral surface of Ophiuroidea. Close up, it is visibly structured, resembling a "madrepore" (stone coral, Scleractinia) colony. From this, it derives its name. The water vascular system of the sea star consists of a series of seawater-filled ducts that function in locomotion and feeding and respiration. Its main parts are the madreporite, the stone canal, the ring canal, the radial canals, the lateral canals, and the tube feet. The sieve-like madreporite allows entry of seawater into the stone canal, which connects to the ring canal around the mouth. Five or more radial canals extend from the ring canal, one in each arm above the ambulacral groove. From th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_(19185438555).jpg "Click for more on -> Clarion Island")
