Lamprey (sometimes also called, inaccurate, lamprey eels ) is an ancient line of jawless fish from the order of Petromyzontiformes, placed in the Cyclostomata superclass. Adult Lamprey can be characterized by mouth-toothed like a funnel. The common name "lamprey" may be derived from Latin lampetra , which may mean "stone licker" ( lambere "to lick" petra "stone" ), although its etymology is uncertain.
There are about 38 species of lampreys known. "Parasitic," carnivorous species are the most famous, and eat by washing into the flesh of other fish to suck their blood; but only 18 lampley species are involved in this lifestyle (more precisely known as "micro predation"). Of the 18 species of parasites, nine are anadromous (some of them also have a freshwater population), and nine live exclusively in freshwater. Also all non-parasitic forms are freshwater species. Lamprey carnivores also attach themselves to larger animals to get a free ride. Adults of non-carnivorous species do not feed; they live from the reserves obtained as ammocoetes (larvae), which they obtain by filtration.
Video Lamprey
Distribution
Lamprey lives mostly in coastal waters and is fresh, although some species (eg Geotria australis , Petromyzon marinus , and Entosphenus tridentatus ) cover significant distances in open oceans, as evidenced by the lack of reproductive isolation among populations. Some species are found in lakes that are locked on land. They are found in temperate regions except in Africa. Their larvae ( ammocoetes ) have low tolerance to high water temperatures, which may explain why they are not distributed in the tropics.
Lamprey distribution may be affected by overfishing and pollution. In England, at the time of the Conquest, lampreys were found as far upstream on the Thames as Petersham. Reduction of pollution on the River Thames and Rivers has led to recent sightings in London and Chester-le-Street.
Distribution may also be affected by dams and other construction projects that disrupt migration routes, blocking access to spawning grounds. In contrast, artificial channel development has exposed new habitats to colonization especially in North America where sea lampreys have become significantly introduced pests on the Great Lakes. Active control programs to control lampreys were modified due to concerns about the quality of drinking water in some areas.
Maps Lamprey
Biology
Superficial adults resemble eels because they have an unformed and elongated body, and can range from 13 to 100 cm (5 to 40 inches) in length. Lack of paired fins, adult lamprey has large eyes, one nostril at the top of the head, and seven gills on each side of the head. Pharynx is divided; the abdomen forms a breathing tube that is isolated from the mouth by a valve called a velum.
This is an adaptation to how adults feed, by preventing body fluids from falling out of the gills or interfering with gas exchange, which occurs by pumping water in and out of the gill pocket rather than carrying it through the mouth. Near the gills there is the eye, which is not well developed and buried beneath the skin inside the larvae. The eyes complete their development during metamorphosis, and are covered by thin and transparent skin layers that become opaque in preservatives. Their teeth consist of meshwork of keratin filaments and other proteins.
The unique morphological characteristics of lampreys, such as the skeleton of their cartilage, suggest they are taxon brothers (see cladistics) of all living jawed vertebrates (gnathostomes), and are usually considered the most basic baseball groups. Instead of a true vertebra, they have a series of cartilage structures called arcualia arranged on a notochord. Hagfish, which resemble lampreys, has traditionally been regarded as the taxon brothers of the true vertebrates (lampreys and gnathostomes) but DNA evidence suggests that they are actually taxon brothers of lampreys.
Research has shown that lamprey is one of the most energy-efficient swimmers. Their swimming movement produces low pressure zones around their bodies, which are attractive rather than pushing their bodies through water.
The last lamprey ancestor's ancestor seems to have specialized to eat the blood and body fluids of other fish after metamorphosis. They attach their mouths to the animal's target body, then use three horny plates (laminae) on the tip of their piston-like tongue, one transverse and two longitudinally placed, to scrape through the surface tissue until they reach the body fluid. Teeth on their verbal discs are the main ones used to help animals attach themselves to their prey. The tooth has a hollow core to provide space for the replacement gear that grows under the old one. Some forms of genuine blood supply have evolved into species that feed on blood and flesh, and some that have become special for meat eating and may even invade host internal organs. The tissue feeder may also involve teeth on an oral disc in the tissue excision. As a result meat feeders have smaller buccal glands because they do not need to produce anticoagulants continuously and the mechanisms to prevent solids entering the bag of branches can potentially block the gills. A study of gastric contents of some lampreys has shown the residual intestines, fins and spine of its prey. Although attacks on humans do occur, they generally will not attack humans except starvation.
The parasitic form has given rise to non-parasitic species, and the "giant" individual among the small American lightrey has sometimes been observed, leading to the hypothesis that sometimes individual members of non-parasitic forms return to the parasitic lifestyles of their ancestors.
Research on marine lampreys has revealed that adult males sexually use a special heat-producing tissue in the form of a ridge of fat cells near the anterior dorsal fin to stimulate women. After attracting women with pheromones, the heat that women detect through body contact will encourage spawning.
Lamprey provides valuable insights into the adaptive immune system, as they have adaptive immunity that evolves convergently with T cell-functioning cells and B cells seen in higher vertebrates. Lamprey leukocytes express variable surface lymphocyte receptor (VLR) resulting from somatic recombination from the leucine-rich gene segment gene in a gene-independent reactivation.
North Lamprey (Petromyzontidae) has the highest number of chromosomes (164-174) between vertebrates.
Lamprey dragon larvae ( Geotria australis ) also have very high tolerance for free iron in their bodies, and have well-developed biochemical systems for the detoxification of large quantities of these metal ions.
Lamprey is the only verterbrate that still exists to have four eyes. Most lampreys have two additional parietal eyes: pineal and parapineal (exceptions are members of Mordacia ).
Life cycle
Adults spawn sand nests, gravel and pebbles in clean rivers, and after hatching from eggs, young larvae - called ammocoetes - will drift downstream with the current until it reaches soft and smooth deposits on silt beds, where they will hide in mud, mud and detritus, taking existence as a filter feeder, collecting detritus, algae, and microorganisms. The eyes of larvae have not developed, but are able to distinguish changes in lighting. Ammocoetes can grow from 3-4 inches (8-10 cm) to about 8 inches (20 cm). Many species change color during the diurnal cycle, becoming dark during the day and pale at night. The skin also has photoreceptors, the cells are light sensitive, mostly concentrated in the tail, which helps them to remain buried. Lamprey can spend up to eight years as ammocoetes, whereas species such as the Arctic lamprey can only spend one to two years as larvae, before undergoing a metamorphosis that generally lasts 3-4 months, but may vary between species. When morphed, they do not eat.
Moving water rates across all of the ammocoetes fittings are among the lowest recorded in suspended animals, and therefore they need nutrient-rich water to meet their nutritional needs. While most suspension feeders (invertebrates) develop in waters containing less than 1 mg of organic solids per liter (& gt; 1 mg/l), ammocoetes requires a minimum of 4 mg/l, with concentrations in their habitat measured up to 40 mg/l.
During lamprey metamorphosis loses both the gallbladder and the bile ducts, and the endostyle turns into the thyroid gland.
Some species, including those that do not parasite and do not feed even after metamorphosis, live in fresh water for their entire life cycle, lay eggs and die shortly after morphed. Conversely, many species are anadromous and migrate into the sea, starting to prey on other animals while still swimming downstream after their metamorphosis gives them eyes, teeth, and mouth sucking. Those who are anadromous are parasites, feeding on fish or marine mammals.
Lamprey anadromous spent up to four years at sea before migrating back to the fresh water where they lay their eggs. Adults make nests (called redds) by moving stones, and females release thousands of eggs, sometimes up to 100,000. Men, intertwined with females, fertilize eggs simultaneously. Being semelparous, both adults die after the egg is fertilized.
Classification
Taxonomists place lampreys and hagfish in the Vertebrate subphylum of the Chordata phylum, which also includes subvertila subphyla Tunicata (sea-squirts) and fish-like Cephalochordata (lancelet or Amphioxus). Recent molecular and morphological phylogenetic studies place lampreys and hagfish in the Agnatha superclass or Agnathostomata (both mean without jaws). Other vertebrate superclasses are Gnathostomata (jaw mouth) and include Chondrichthyes (shark) classes, Osteichthyes (bony fish), Amphibia, Reptilia, Aves, and Mammals.
Some researchers have classified lampreys as the only surviving representatives of the Linnean Cephalaspidomorphi class. Cephalaspidomorpha is sometimes given as a subclass of Cephalaspidomorphi. Fossil evidence now shows lampreys and cephalaspids acquiring their common character with convergent evolution. Thus, many newer works, such as the fourth edition of Fishes of the World, classify lampreys in a separate group called Hyperoartia or Petromyzontida, but whether this is actually a contentious clade. Namely, it has been suggested that non-lamprey "Hyperoartia" is actually closer to jawed vertebrates.
The debate about their systematics though, lampreys is a sequence of Petromyzontiformes . Sometimes still visible is the alternative spell "Petromyzoniformes" , based on the argument that the genus of its kind is Petromyzon and not "Petromyzonta" or similar. Throughout much of the 20th century, both names were used quite a lot indiscriminately, even by the same authors in subsequent publications. In the mid-1970s, ICZN was called to fix one name or another, and after much debate had to solve the problem by voting. Thus, in 1980, the spelling with "t" prevailed, and in 1981, it became official that all higher-level taxa based on Petromyzon should start with "Petromyzont-".
The following taxonomy is based on treatments by FishBase as of April 2012 with the phylogeny composed by Mikko Haaramo. In that order there are 10 genera that live in three families. Two of the latter are monotypic at the level of the genus today, and in one of them a living species is recognized (though it may be a mysterious species complex):
Fossil record
Lamprey's fossils are rare because cartilage does not fossilize like bones. The first lampley fossils originally found in Early Carbon limestone, marine sediments in North America: Mayomyzon pieckoensis and Hardistiella montanensis of Mississippian Mazon Creek lagerstÃÆ'¤tte > and the Lime sequence of Bear Gulch. None of the lamprey fossils found to date have been over 10 cm (3.9 inches), and all Paleozoic forms have been found in marine sediments.
In the June 22, 2006 edition of Nature, Mee-mann Chang and colleagues reported on the fossil lamprey of the Inner Mongolia Yixian Formation. The new species, morphologically similar to Carbon and other shapes, are named Mesomyzon mengae ("Lampilla Mesozoic Meng Qingwen").
A well-preserved fossil shows a well-developed oral suction disk, a relatively long dental tool showing branch baskets, seven gill pockets, gill arches, and even gill filament impression, and about 80 miomeres of muscles. Unlike North American fossils, the habitat is almost certainly fresh water.
Months later, lampley fossils even older than the Mazon Creek genera were reported from the rocks of Witteberg Group near Grahamstown, in the Eastern Cape of South Africa. This species, Priscomyzon riniensis , is very similar to the lampreys found today.
Use in research
Lamprey has been studied extensively because his relatively simple brain is thought to be in many ways to reflect the structure of the ancestral brain of early vertebrates. Beginning in the 1970s, Sten Grillner and his colleagues at the Karolinska Institute in Stockholm followed from extensive work in Lamprey started by Carl Rovainen in the 1960s who used lampreys as a model system to find out the basic principles of motor control in vertebrates. start in the spinal cord and work towards the brain.
In a series of studies by Rovainen and his disciple James Buchanan, the cells that form the neural circuits within the spinal cord are capable of producing rhythmic motor patterns that underlie swimming are examined. Note that there are still details missing in the networking scheme despite the claims of Grillner that the network is characterized (Parker 2006, 2010). The spinal cord circuits are controlled by specific locomotor areas in the brain stem and midbrain, and these areas are in turn controlled by higher brain structures, including basal ganglia and texts.
In a study of lamprey tectum published in 2007, they found electrical stimulation may cause eye movement, lateral bending motion, or swimming activity, and the type, amplitude, and direction of movement vary as a function of the location within the stimulated tone. This finding is interpreted as consistent with the idea that the trigger produces a drive aimed at the goal at the lamprey.
Lampreys are used as model organisms in biomedical research, in which their large reticulocospital axons are used to investigate synaptic transmission. The lamprey's axon is very large and allows for the microinjection of substances for experimental manipulation.
They are also capable of full functional recovery after complete spinal cord transection. Another feature is the ability to remove several genes from their somatic cell lineage, about 20% of their DNA, which is important during embryo delopment, but which in humans can cause problems such as cancer later on, after they serve them. aim. How genes intended for targeted removal are unknown.
In human culture
As food
Lamprey has long been used as food for humans. They were greatly appreciated by the ancient Romans. During the Middle Ages, they were widely eaten by the upper classes throughout Europe - especially during Lent time when meat eating was forbidden, because of the flavor and texture of their flesh. King Henry I of England admitted to loving lamprey that he often ate it until he was dissolved in life and ill health with his doctor's advice about their wealth, and was said to have died from eating the "lamprey ranks". Whether or not pampering lamprey really causes his death is not clear.
On March 4, 1953, the coronation cake of Queen Elizabeth II was made by the Royal Air Force using lampreys.
In southeastern Europe (Portugal, Spain, and France), half of northern Finland and Latvia (where lampreys are routinely sold in supermarkets), larger lampreys are still a precious delicacy. Sea lamprey is the most sought-after species in Portugal and one of the two that can legally bear the commercial name "lamprey" ( lampreia ): the other is Lampyra fluviatilis , lamprey river Europe, both according to Portaria (Government Regulation No. 587/2006, from 22 June). Overfishing has reduced their numbers in those parts. Lamprey is also consumed in Sweden, Russia, Lithuania, Estonia, Japan, and South Korea. In Finland, they are commonly sold pickles in vinegar.
Mucus and serum from several lamprey species, including lamprey Caspian ( Caspiomyzon wagneri ), lamprey river ( Lampetra fluviatilis and L. planeri ), and lamprey sea ​​( Petromyzon marinus ), is known to be toxic, and requires a thorough cleaning before cooking and consumption.
In England, lampreys are commonly used as bait, usually as dead bait. The northern spears, altars, and chubs can all be captured in lamprey. Frozen Lamprey can be purchased from most bait and tackle shops.
As pest
Sea lamprey has become a major pest in the Great Lakes of North America. It is generally believed that they gained access to the lake through canals during the early 20th century, but this theory is controversial. They are considered as invasive species, have no natural enemies in the lake, and prey on many species of commercial value, such as lake trout.
Lamprey is now commonly found in rivers that feed the lake, and is controlled with special barriers to prevent upstream movement of adults, or by the application of toxins called lampricides, which are harmless to most other aquatic species; However, the programs are complicated and expensive, and do not eliminate lampreys from the lake, but only keep them in check.
New programs are being developed, including the use of male sterilized sterilized males with methods similar to sterile insect techniques. Finally, important pheromones for lamprey migration behavior have been isolated, their chemical structures determined, and their impact on lamprey behavior are studied, in laboratory and in the wild, and active efforts are being made for chemical resources and to overcome regulatory considerations that may allow this strategy to proceed.
The control of the marine lamprey on the Great Lakes was conducted by the US Fish and Wildlife Agency and the Canadian Department of Fisheries and Marine, and was coordinated by the Great Lakes Fisheries Commission. Lake Champlain, bordered by New York, Vermont, and Quebec, and the Finger Lakes of New York is also home to a high population of sea lamprey that ensures control. Lake Champlain's lamprey control program is managed by the New York State Department of Environmental Conservation, the Vermont Fish and Wildlife Department, and the US Fish and Wildlife Service. The Lake New York lake light control program is fully managed by the New York State Department of Environmental Conservation.
In folklore
In folklore, lamprey is called a "nine-eyed eel". The name comes from seven external gill slits which, together with one nostril and one eye, line each side of the lamprey's head. Likewise, the German word for lamprey is Neunauge , meaning "nine eyes", and in Japanese they are called yatsume-unagi (????, "eight eels "), which does not include the nostrils of the count.
In the literature
Vedius Pollio keeps a lamprey pool where the slave who expels his displeasure will be cast as food. On one occasion, Vedius was punished by Augustus for trying to do it in his presence:
... one of his slaves has broken the crystal cup. Vedius ordered him to be confiscated and then put to death, but in an unusual way. He orders him to be thrown into the big lamprey that is in his fish pond. Who would not have thought he was doing this for display? But it was not because of cruelty. The boy slipped from the kidnapper's hand and fled to Augustus's feet without asking anything but another way to die - he did not want to be eaten. Augustus was moved by the novelty of cruelty and ordered him to be released, all crystal mugs to be solved before his eyes, and fish ponds to be filled...
This incident was included in the plot plot 2003 Pompeii by Robert Harris in the incident of Ampliatus feeding the boy to his lamprey.
Lucius Licinius Crassus was ridiculed by Gnaeus Domitius Ahenobarbus (cos 54 BC) for weeping over the death of his pet lamprey:
So when Domitius told Crassus the orator, Did you not cry because of the lamprey death you stored in your fish pond? - Are not you, Crassus told him again, burying three wives without ever shedding tears? - Plutarch, In Animal Intelligence , 976a
The story is also found in Aelian (Various Histories VII, 4) and Macrobius (Saturnalia III.15.3). These include by Hugo von Hofmannsthal in Sura Chandos:
And in my mind I compare myself from time to time with Crassus's orator, who reported that he grew so enamored with the benign lamprey - a foolish, apathetic fish, red-eyed in his ornamental pond - that it became talk of the city; and when one day in the Domitius Senate denounced him for shedding tears on the death of this fish, trying to make him look stupid, Crassus replied, "So I have done for the death of my fish as you had during death not your first or second wife. " I do not know how often this Crassus with its lamprey comes into my mind as a reflection of my Mirror of Self, reflected in the abyss of centuries.
In the series of George R. R. Martin novels, A Song of Ice and Fire, Lord Wyman Manderly is mockingly called "Lord Lamprey" by his subjects in reference to his rumored proximity to lamprey pie and his striking obesity.
Source of the article : Wikipedia
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