|
Galaxias Paucispondylus
The alpine river galaxias (''Galaxias paucispondylus'') is a galaxiid of the genus '' Galaxias'', found only in mid to high elevation streams flowing from the Southern Alps of New Zealand. It grows to a length of up to 11 cm. Alpine galaxias are speckled olive-green over a light brown base. The single large dorsal fin is rounded, and set back two thirds of the body length, the anal fin a little further back. The caudal fin is large and slightly forked. Like all galaxiids it lacks scales and has a thick, leathery skin covered with mucus. They are non-diadromous and therefore do not have a marine phase and are not part of the whitebait Whitebait is a collective term for the immature fry of fish, typically between long. Such young fish often travel together in schools along coasts, and move into estuaries and sometimes up rivers where they can be easily caught using fine-m ... catch. References * NIWA June 2006 alpine galaxias Endemic freshwater fish of New Ze ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerald Stokell
Gerald Stokell (20 June 1890 – 10 July 1972) was a New Zealand amateur ichthyologist.Journal of the Royal Society of New Zealanp 324/ref> Early life Stokell was born at Prebbleton, near Christchurch, New Zealand, on 20 June 1890 to Edmund Stokell and Jane (Née Pasche). He lived there for his whole life. He attended Broadfields Primary School, and was a keen trout angler. Interest in freshwater fish A keen angler, Stokell wrote a series of studies on trout in Lake Ellismere. Through this interest in angling, he also came across native fish species, but was unable to identify them due to a lack of published information. From 1938 onwards he began publishing papers on them, describing species and detangling the many names that had accrued. He described 10 species that are still accepted, although others turned out to be junior synonyms. Species described * ''Galaxias paucispondylus'' (1938) alpine galaxias * '' Gobiomorphus breviceps'' (1939) upland bully * '' Galaxias prognathu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxiid
The Galaxiidae are a family of mostly small freshwater fish in the Southern Hemisphere. The majority live in Southern Australia or New Zealand, but some are found in South Africa, southern South America, Lord Howe Island, New Caledonia, and the Falkland Islands. One galaxiid species, the common galaxias (''Galaxias maculatus''), is probably the most widely naturally distributed freshwater fish in the Southern Hemisphere. They are coolwater species, found in temperate latitudes, with only one species known from subtropical habitats. Many specialise in living in cold, high-altitude upland and lowland (freshwater ecology), upland rivers, streams, and lakes. Some galaxiids live in fresh water all their lives, but many have a partially marine lifecycle. In these cases, larvae are hatched in a river, but are washed downstream to the ocean, later returning to rivers as juveniles to complete their development to full adulthood. This pattern differs from that of salmon, which only return ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxias
''Galaxias'' is a genus of small freshwater fish in the family (biology), family Galaxiidae, and are frequently referred to as the galaxiids. These highly adaptable fish are typically found at temperate latitudes across the Southern Hemisphere. Galaxiids are fish scale, scaleless and somewhat tubular in body form, ranging from very slender to quite bulky. They are somewhat torpedo-shaped, with the dorsal fin, dorsal and anal fins positioned close to the tail. They are generally small, with typical adults ranging between in total length, with some stocky species attaining around . The largest, ''Galaxias argenteus'', has been recorded at , although is a more typical adult length. Species The 46 recognized species in this genus are: * ''Galaxias aequipinnis'' Tarmo Ain Raadik, Raadik, 2014 (East Gippsland Galaxias) * ''Galaxias anomalus'' Gerald Stokell, Stokell, 1959 (Roundhead Galaxias) * ''Galaxias arcanus'' Raadik, 2014 (Riffle Galaxias) * ''Galaxias argenteus'' Johann Fri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Alps (New Zealand)
The Southern Alps (; officially Southern Alps / Kā Tiritiri o te Moana) is a mountain range extending along much of the length of New Zealand's South Island, reaching its greatest elevations near the range's western side. The name "Southern Alps" generally refers to the entire range, although separate names are given to many of the smaller ranges that form part of it. The range includes the South Island's Main Divide, which separates the water catchments of the more heavily populated eastern side of the island from those on the west coast. Politically, the Main Divide forms the boundary between the Marlborough, Canterbury and Otago regions to the southeast and the Tasman and West Coast regions to the northwest. Names The Māori name of the range is , meaning "the Mirage of the Ocean". The English explorer James Cook bestowed the name ''Southern Alps'' on 23 March 1770, admiring their "prodigious height". p. 384. They had previously been noted by Abel Tasman in 1642, whose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through convergent evolution they have independently evolved external superficial fish-like body plans adapted to their marine environments, including most numerously fish, but also mammals such as cetaceans (whales, dolphins, and porpoises), and even extinct ancient marine reptiles such as various known species of ichthyosaurs. Most species have only one dorsal fin, but some have two or three. Wildlife biologists often use the distinctive nicks and wear patterns which develop on the dorsal fins of large cetaceans to identify individuals in the field. The bony or cartilaginous bones that support the base of the dorsal fin in fish are called ''pterygiophores''. Functions The main purpose of the dorsal fin is to stabilize the animal against rollin ... [...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] |
Caudal 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] |
Scale (zoology)
In most biological nomenclature, a scale ( grc, λεπίς, lepís; la, squāma) is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran (butterfly and moth) species, scales are plates on the surface of the insect wing, and provide coloration. Scales are quite common and have evolved multiple times through convergent evolution, with varying structure and function. Scales are generally classified as part of an organism's integumentary system. There are various types of scales according to shape and to class of animal. Fish scales File:Ganoid scales.png, Ganoid scales on a carboniferous fish ''Amblypterus striatus'' File:Denticules cutanés du requin citron Negaprion brevirostris vus au microscope électronique à balayage.jpg, Placoid scales on a lemon shark (''Negaprion brevirostris'') File:RutilusRutilusScalesLateralLine.JPG, Cycloid scales on a common roach (''Rutilus rutilus'') Fish scales are dermally derived, specifically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucus
Mucus ( ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It is a viscous colloid containing inorganic salts, antimicrobial enzymes (such as lysozymes), immunoglobulins (especially IgA), and glycoproteins such as lactoferrin and mucins, which are produced by goblet cells in the mucous membranes and submucosal glands. Mucus serves to protect epithelial cells in the linings of the respiratory, digestive, and urogenital systems, and structures in the visual and auditory systems from pathogenic fungi, bacteria and viruses. Most of the mucus in the body is produced in the gastrointestinal tract. Amphibians, fish, snails, slugs, and some other invertebrates also produce external mucus from their epidermis as protection against pathogens, and to help in movement and is also produced in fish to line the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diadromous
Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear. Fish migrations involve movements of schools of fish on a scale and duration larger than those arising during normal daily activities. Some particular types of migration are ''anadromous'', in which adult fish live in the sea and migrate into fresh water to spawn; and ''catadromous'', in which adult fish live in fresh water and migrate into salt water to spawn. Marine forage fish often make large migrations between their spawning, feeding and nursery grounds. Movements are associated with ocean currents and with the availability of food in different areas at different times of year. The migratory movements ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> Anal Fin")
.jpg "Click for more on -> Scale (zoology)")
