|
Long Tom (fish)
Needlefish (family Belonidae) or long toms are piscivorous fishes primarily associated with very shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments (e.g., ''Strongylura''), while a few genera are confined to freshwater rivers and streams, including '' Belonion'', ''Potamorrhaphis'', and ''Xenentodon''. Needlefish closely resemble North American freshwater gars (family Lepisosteidae) in being elongated and having long, narrow jaws filled with sharp teeth, and some species of needlefishes are referred to as gars or garfish despite being only distantly related to the true gars. In fact, the name "garfish" was originally used for the needlefish ''Belone belone'' in Europe and only later applied to the North American fishes by European settlers during the 18th century. Description Needlefish are slender, ranging from in length. They have a single dorsal fin, placed far back on the body, almost op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tylosurus Crocodilus
The houndfish (''Tylosurus crocodilus'') is a game fish of the family Belonidae. It is the largest member of its family, growing up to in length and in weight. It is also often called the crocodile needlefish. Description While the houndfish has no spines, its dorsal fin has 21–25 soft rays, and its anal fin has 19–22. They are also known to have 80–86 vertebrae. A key way of distinguishing the houndfish from other members of the genus ''Tylosurus'' is that the houndfish's teeth point anteriorly when the fish is a juvenile. The teeth of other species are straight at all ages.Collette, B.B. 1999 Belonidae. Needlefishes. p. 2151-2161. In: K.E. Carpenter and V.H. Niem (eds.) FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 4. Bony fishes part 2 (Mugilidae to Carangidae). FAO, Rome. The houndfish also has a more stout, cylindrical body and a shorter head than other needlefishes. They have dark blue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lepisosteidae
Gars are members of the family Lepisosteidae, which are the only surviving members of the Ginglymodi, an ancient holosteian group of ray-finned fish, which first appeared during the Triassic, over 240 million years ago. Gars comprise seven living species of fish in two genera that inhabit fresh, brackish, and occasionally marine waters of eastern North America, Central America and Cuba in the Caribbean, though extinct members of the family were more widespread. Gars have elongated bodies that are heavily armored with ganoid scales, and fronted by similarly elongated jaws filled with long, sharp teeth. Gars are sometimes referred to as "garpike", but are not closely related to pike, which are in the fish family Esocidae. All of the gars are relatively large fish, but the alligator gar (''Atractosteus spatula'') is the largest; the alligator gar often grows to a length over and a weight over , and specimens of up to in length have been reported. Unusually, their vascularised sw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Needlefish Is Being Cleaned By Labroides Phthirophagus
Needlefish (family Belonidae) or long toms are piscivorous fishes primarily associated with very shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments (e.g., ''Strongylura''), while a few genera are confined to freshwater rivers and streams, including '' Belonion'', '' Potamorrhaphis'', and ''Xenentodon''. Needlefish closely resemble North American freshwater gars (family Lepisosteidae) in being elongated and having long, narrow jaws filled with sharp teeth, and some species of needlefishes are referred to as gars or garfish despite being only distantly related to the true gars. In fact, the name "garfish" was originally used for the needlefish ''Belone belone'' in Europe and only later applied to the North American fishes by European settlers during the 18th century. Description Needlefish are slender, ranging from in length. They have a single dorsal fin, placed far back on the body, almost o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Refraction
In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and water waves also experience refraction. How much a wave is refracted is determined by the change in wave speed and the initial direction of wave propagation relative to the direction of change in speed. For light, refraction follows Snell's law, which states that, for a given pair of media, the ratio of the sines of the angle of incidence ''θ1'' and angle of refraction ''θ2'' is equal to the ratio of phase velocities (''v''1 / ''v''2) in the two media, or equivalently, to the refractive indices (''n''2 / ''n''1) of the two media. :\frac =\frac=\frac Optical prisms and lenses use refraction to redirect light, as does the human eye. The refractive index of materials varies with the wavel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snell's Window
Snell's window (also called Snell's circle or optical man-hole) is a phenomenon by which an underwater viewer sees everything above the surface through a cone of light of width of about 96 degrees. This phenomenon is caused by refraction of light entering water, and is governed by Snell's Law. The area outside Snell's window will either be completely dark or show a reflection of underwater objects by total internal reflection. Underwater photographers sometimes compose photographs from below such that their subjects fall inside Snell's window, which backlights and focuses attention on the subjects. Image formation Under ideal conditions, an observer looking up at the water surface from underneath sees a perfectly circular image of the entire above-water hemisphere—from horizon to horizon. Due to refraction at the air/water boundary, Snell's window compresses a 180° angle of view above water to a 97° angle of view below water, similar to the effect of a fisheye lens. The br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalopod
A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology. Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two, only distantly related, extant subclasses: Coleoidea, which includes octopuses, squid, and cuttlefish; and Nautiloidea, represented by ''Nautilus'' and ''Allonautilus''. In the Coleoidea, the molluscan shell has been internalized or is absent, whereas in the Nautiloidea, the external shell remains. About 800 living species of cephalopods have been ident ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krill
Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian Norwegian, Norwayan, or Norsk may refer to: *Something of, from, or related to Norway, a country in northwestern Europe * Norwegians, both a nation and an ethnic group native to Norway * Demographics of Norway *The Norwegian language, including ... word ', meaning "small fry of fish", which is also often attributed to species of fish. Krill are considered an important trophic level connection – near the bottom of the food chain. They feed on phytoplankton and (to a lesser extent) zooplankton, yet also are the main source of food for many larger animals. In the Southern Ocean, one species, the Antarctic krill, ''Euphausia superba'', makes up an estimated biomass (ecology), biomass of around 379,000,000 tonnes, making it among the species with the largest total biomass. Over half of this biomass is eaten by whales, Pinniped, seals, pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Needlefish2
Needlefish (family Belonidae) or long toms are piscivorous fishes primarily associated with very shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments (e.g., ''Strongylura''), while a few genera are confined to freshwater rivers and streams, including '' Belonion'', '' Potamorrhaphis'', and ''Xenentodon''. Needlefish closely resemble North American freshwater gars (family Lepisosteidae) in being elongated and having long, narrow jaws filled with sharp teeth, and some species of needlefishes are referred to as gars or garfish despite being only distantly related to the true gars. In fact, the name "garfish" was originally used for the needlefish ''Belone belone'' in Europe and only later applied to the North American fishes by European settlers during the 18th century. Description Needlefish are slender, ranging from in length. They have a single dorsal fin, placed far back on the body, almost o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuna
A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max length: , weight: ) up to the Atlantic bluefin tuna (max length: , weight: ), which averages and is believed to live up to 50 years. Tuna, opah and mackerel sharks are the only species of fish that can maintain a body temperature higher than that of the surrounding water. An active and agile predator, the tuna has a sleek, streamlined body, and is among the fastest-swimming pelagic fish – the yellowfin tuna, for example, is capable of speeds of up to . Greatly inflated speeds can be found in early scientific reports and are still widely reported in the popular literature. Found in warm seas, the tuna is commercially fished extensively as a food fish, and is popular as a bluewater game fish. As a result of overfishing, some tuna species, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anal Fin
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles. Their principal function is to help the fish swim. Fins located in different places on the fish serve different purposes such as moving forward, turning, keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to lu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Cephalopod")
.png "Click for more on -> Anal Fin")