Task: Question Answering
Input (English): Context: The giant oarfish ("Regalecus glesne") is a species of oarfish of the family Regalecidae. It is an oceanodromous species with a worldwide distribution, excluding polar regions. Other common names include Pacific oarfish, king of herrings, ribbonfish, and streamer fish., Brackish water or briny water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak". Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms)., Seahorse is the name given to 54 species of small marine fishes in the genus Hippocampus. "Hippocampus" comes from the Ancient Greek word "hippos" meaning "horse" and "kampos" meaning "sea monster". The word "seahorse" can also be written as two separate words (sea horse), or hyphenated (sea-horse). Having a head and neck suggestive of a horse, seahorses also feature segmented bony armour, an upright posture and a curled prehensile tail., The ghost knifefishes are a family, Apteronotidae, of ray-finned fishes in the order Gymnotiformes. These fish can be found in the freshwater of Panama and South America., An electric fish is any fish that can generate electric fields. A fish that can generate electric fields is said to be "electrogenic" while a fish that has the ability to detect electric fields is said to be "electroreceptive". Most electrogenic fish are also electroreceptive. Electric fish species can be found both in the ocean and in freshwater rivers of South America (Gymnotiformes) and Africa (Mormyridae). Many fish such as sharks, rays and catfishes can detect electric fields and are thus electroreceptive, but they are not classified as electric fish because they cannot generate electricity. Most common bony fish (teleosts), including most fish kept in aquaria or caught for food, are neither electrogenic nor electroreceptive., Total dissolved solids (TDS) is a measure of the combined content of all inorganic and organic substances contained in a liquid in molecular, ionized or micro-granular (colloidal sol) suspended form. Generally the operational definition is that the solids must be small enough to survive filtration through a filter with two-micrometer (nominal size, or smaller) pores. Total dissolved solids are normally discussed only for freshwater systems, as salinity includes some of the ions constituting the definition of TDS. The principal application of TDS is in the study of water quality for streams, rivers and lakes, although TDS is not generally considered a primary pollutant (e.g. it is not deemed to be associated with health effects) it is used as an indication of aesthetic characteristics of drinking water and as an aggregate indicator of the presence of a broad array of chemical contaminants., Venezuela, officially the Bolivarian Republic of Venezuela, is a federal republic located on the northern coast of South America. It is bordered by Colombia on the west, Brazil on the south, Guyana on the east, and the islands of Trinidad and Tobago to the north-east. Venezuela's territory covers around with an estimated population . Venezuela is considered a state with extremely high biodiversity (currently ranks 7th in the world's list of nations with the most number of species), with habitats ranging from the Andes Mountains in the west to the Amazon Basin rain-forest in the south, via extensive "llanos" plains and Caribbean coast in the center and the Orinoco River Delta in the east., Table salt or common salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in its natural form as a crystalline mineral is known as rock salt or halite. Salt is present in vast quantities in seawater, where it is the main mineral constituent. The open ocean has about of solids per litre, a salinity of 3.5%., An iceberg or ice mountain is a large piece of freshwater ice that has broken off a glacier or an ice shelf and is floating freely in open water. It may subsequently become frozen into pack ice (one form of sea ice). As it drifts into shallower waters, it may come into contact with the seabed, a process referred to as seabed gouging by ice. Almost 91% of an iceberg is below the surface of the water. , The banded knifefish ("Gymnotus carapo") is a knifefish native to South America., The black ghost knifefish ("Apteronotus albifrons") is a tropical fish belong to the ghost knifefish family (Apteronotidae). They originate in freshwater habitats in South America where ranging from Venezuela to the ParaguayParaná River, including the Amazon Basin. They are popular in aquaria. The fish is all black except for two white rings on its tail, and a white blaze on its nose, which can occasionally extend into a stripe down its back. It moves mainly by undulating a long fin on its underside. It will grow to a maximum length of . It does not have scales., Photocorynus spiniceps is a species of anglerfish in the family Linophrynidae. It is in the monotypic genus "Photocorynus"., An eel is any fish belonging to the order Anguilliformes, which consists of four suborders, 20 families, 111 genera and about 800 species. Most eels are predators. The term "eel" (originally referring to the European eel) is also used for some other similarly shaped fish, such as electric eels and spiny eels, but these are not members of the Anguilliformes order., The Gymnotiformes are a group of teleost bony fishes commonly known as the Neotropical or South American knifefish . They have long bodies and swim using undulations of their elongated anal fin . Found exclusively in fresh water , these mostly nocturnal fish are capable of producing electric fields for navigation , communication , and , in the case of the electric eel ( Electrophorus electricus ) , attack and defense . A few species are familiar to the aquarium trade , such as the black ghost knifefish ( Apteronotus albifrons ) , the glass knifefish ( Eigenmannia virescens ) , and the banded knifefish ( Gymnotus carapo ) ., A sea is a large body of salt water that is surrounded in whole or in part by land. More broadly, "the sea" is the interconnected system of Earth's salty, oceanic watersconsidered as one global ocean or as several principal oceanic divisions. The sea moderates Earth's climate and has important roles in the water cycle, carbon cycle, and nitrogen cycle. Although the sea has been traveled and explored since prehistory, the modern scientific study of the seaoceanographydates broadly to the British "Challenger" expedition of the 1870s. The sea is conventionally divided into up to five large oceanic sectionsincluding the International Hydrographic Organization's four named oceans (the Atlantic, Pacific, Indian, and Arctic) and the Southern Ocean; smaller, second-order sections, such as the Mediterranean, are known as "seas"., A glacier (or ) is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries. Glaciers slowly deform and flow due to stresses induced by their weight, creating crevasses, seracs, and other distinguishing features. They also abrade rock and debris from their substrate to create landforms such as cirques and moraines. Glaciers form only on land and are distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water., The Paraná River is a river in south Central South America, running through Brazil, Paraguay, and Argentina for some . It is second in length only to the Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the Tupi language and means "like the sea" (that is, "as big as the sea"). It merges first with the Paraguay River and then farther downstream with the Uruguay River to form the Río de la Plata and empties into the Atlantic Ocean., Actinopterygii , or the ray-finned fishes, constitute a class or subclass of the bony fishes., The electric eel ("Electrophorus electricus") is an electric fish, and the only species in its genus. Despite the name, it is not an eel, but rather a knifefish., A stream is a body of water with a current, confined within a bed and banks. Depending on its location or certain characteristics, a stream may be referred to as a "bayou", "beck", "branch", "brook", "burn", "creek", "crick", "ghyll", "gill", "kill", "lick", "mill race", "race", "rill", "river", "rivulet", "run", "runnel", "streamage", "syke", or "wash"., Anglerfishes are fish of the teleost order Lophiiformes . They are bony fish named for their characteristic mode of predation, in which a fleshy growth from the fish's head (the esca or illicium) acts as a lure., Glass knifefishes are fishes in the family Sternopygidae in the order Gymnotiformes. Species are also known as rattail knifefishes., Fresh water is naturally occurring water on Earth's surface in ice sheets, ice caps, glaciers, icebergs, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and brackish water although it does include mineral-rich waters such as chalybeate springs. The term "sweet water" (from Spanish "agua dulce") has been used to describe fresh water in contrast to salt water. The term fresh water does not have the same meaning as potable water. Much of the surface fresh water and ground water is unsuitable for drinking without some form of purification because of the presence of chemical or biological contaminants., The Triassic is a geologic period and system which spans 50.9 million years from the end of the Permian Period million years ago (Mya), to the beginning of the Jurassic Period Mya. The Triassic is the first period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic was named in 1834 by Friedrich von Alberti, after the three distinct rock layers ("tri" meaning "three") that are found throughout Germany and northwestern Europered beds, capped by marine limestone, followed by a series of terrestrial mud- and sandstonescalled the "Trias"., The ocean sunfish or common mola ("Mola mola") is the heaviest known bony fish in the world. It has an average adult weight between . The species is native to tropical and temperate waters around the globe. It resembles a fish head with a tail, and its main body is flattened laterally. Sunfish can be as tall as they are long when their dorsal and ventral fins are extended., A fish is any member of a group of organisms that consist of all gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Tetrapods emerged within lobe-finned fishes, so cladistically they are fish as well. However, traditionally fish are rendered obsolete or paraphyletic by excluding the tetrapods (i.e., the amphibians, reptiles, birds and mammals which all descended from within the same ancestry). Because in this manner the term "fish" is defined negatively as a paraphyletic group, it is not considered a formal taxonomic grouping in systematic biology. The traditional term pisces (also ichthyes) is considered a typological, but not a phylogenetic classification., Groundwater (or ground water) is the water present beneath Earth's surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from, and eventually flows to, the surface naturally; natural discharge often occurs at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology., The teleosts or Teleostei (Greek: "teleios", "complete" + "osteon", "bone") are by far the largest infraclass in the class Actinopterygii, the ray-finned fishes, and make up 96 percent of all fish. This diverse group arose in the Triassic period and members are arranged in about 40 orders and 448 families. Over 26,000 species have been described. Teleosts range from giant oarfish, measuring or more, and ocean sunfish weighing over , to the minute male anglerfish "Photocorynus spiniceps", just long. As well as torpedo-shaped fish built for speed, teleosts can be flattened vertically or horizontally, be elongated cylinders or take specialised shapes as in anglerfish and seahorses. Teleosts dominate the seas from pole to pole and inhabit the ocean depths, estuaries, rivers, lakes and even swamps., Subject: gymnotiformes, Relation: taxon_rank, Options: (A) branch (B) class (C) family (D) form (E) genus (F) group (G) infraclass (H) order (I) series (J) species (K) subclass
Output (English): order