Pufferfish

Pufferfish

Overview
Tetraodontidae is a family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of primarily marine and estuarine fish of the Tetraodontiformes
Tetraodontiformes
The Tetraodontiformes are an order of highly derived ray-finned fish, also called the Plectognathi. Sometimes these are classified as a suborder of the Perciformes...

order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

. The family includes many familiar species which are variously called pufferfish, balloonfish, blowfish, bubblefish, globefish, swellfish, toadfish, toadies, honey toads, sugar toads, and sea squab. They are morphologically similar to the closely related porcupinefish
Porcupinefish
Porcupinefish are fish of the family Diodontidae, , also commonly called blowfish ....

, which have large external spines (unlike the thinner, hidden spines of Tetraodontidae, which are only visible when the fish has puffed up).
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Encyclopedia
Tetraodontidae is a family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of primarily marine and estuarine fish of the Tetraodontiformes
Tetraodontiformes
The Tetraodontiformes are an order of highly derived ray-finned fish, also called the Plectognathi. Sometimes these are classified as a suborder of the Perciformes...

order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

. The family includes many familiar species which are variously called pufferfish, balloonfish, blowfish, bubblefish, globefish, swellfish, toadfish, toadies, honey toads, sugar toads, and sea squab. They are morphologically similar to the closely related porcupinefish
Porcupinefish
Porcupinefish are fish of the family Diodontidae, , also commonly called blowfish ....

, which have large external spines (unlike the thinner, hidden spines of Tetraodontidae, which are only visible when the fish has puffed up). The scientific name refers to the four large teeth, fused into an upper and lower plate, which are used for crushing the shells of crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s and mollusks, their natural prey.

(Maple) Puffer fish are generally believed to be the second–most poisonous vertebrate
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...

 in the world, after the Golden Poison Frog
Golden Poison Frog
Phyllobates terribilis, the Golden Poison Frog or the Golden Dart Frog, is a poison dart frog endemic to the Pacific coast of Colombia. The optimal habitat of P. terribilis is the rainforest with high rain rates , altitude between 100–200 m, temperature of at least 26 °C, and relative humidity...

. Certain internal organs, such as liver, and sometimes their skin are highly toxic to most animals when eaten, but nevertheless the meat of some species is considered a delicacy in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 (as 河豚, pronounced as fugu
Fugu
is the Japanese word for pufferfish and the dish prepared from it, normally species of genus Takifugu, Lagocephalus, or Sphoeroides, or porcupinefish of the genus Diodon. Fugu can be lethally poisonous due to its tetrodotoxin; therefore, it must be carefully prepared to remove toxic parts and to...

), Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

 (as bok), and China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 (as 河豚 he2 tun2) when prepared by chefs who know which part is safe to eat and in what quantity.

The tetraodontidae contains at least 189 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of puffers in 19 genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

. They are most diverse in the tropics and relatively uncommon in the temperate zone and completely absent from cold waters
Polar region
Earth's polar regions are the areas of the globe surrounding the poles also known as frigid zones. The North Pole and South Pole being the centers, these regions are dominated by the polar ice caps, resting respectively on the Arctic Ocean and the continent of Antarctica...

. They are typically small to medium in size, although a few species can reach lengths of greater than 100 centimetres (39.4 in).

Ecology and life history


Although most species live in inshore and estuarine waters, 29 species spend their entire life cycles in freshwater. These species are found in disjunct tropical regions of South America (1 species), Central Africa (3 species) and Southeast Asia (25 species).

Natural defenses


The puffer's unique and distinctive natural defenses help compensate for their slow locomotion. Puffers move by combining pectoral, dorsal
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

, anal, and caudal fins. This makes them highly maneuverable but very slow, and therefore comparatively easy predation targets. Their tail fin is mainly used as a rudder, but it can be used for a sudden evasive burst of speed that shows none of the care and precision of their usual movements. The puffer's excellent eyesight combined with this speed burst is the first and most important defense against predators. Their back up defense mechanism, used if they are successfully pursued, is to fill their extremely elastic stomach
Stomach
The stomach is a muscular, hollow, dilated part of the alimentary canal which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects , and molluscs. It is involved in the second phase of digestion, following mastication .The stomach is...

s with water (or air when outside the water) until they are much larger and almost spherical
Sphere
A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...

 in shape. Even if they are not visible when the puffer is not inflated, all puffers have pointed spines, so a hungry predator may suddenly find itself facing an unpalatable pointy ball rather than a slow, tasty fish. Predators which don't heed this warning (or who are "lucky" enough to catch the puffer suddenly, before or during inflation) may die from choking, and predators that do manage to swallow the puffer may find their stomachs full of tetrodotoxin
Tetrodotoxin
Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...

, making puffers an unpleasant, possibly lethal, choice of prey. This neurotoxin is found primarily in the ovaries
Ovary
The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...

 and liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...

, although smaller amounts exist in the intestines and skin
Skin
-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...

, as well as trace amounts in muscle. It does not always have a lethal effect on large predators, such as sharks, but it can kill humans.

Not all puffers are necessarily poisonous; Takifugu oblongus, for example, is a fugu
Fugu
is the Japanese word for pufferfish and the dish prepared from it, normally species of genus Takifugu, Lagocephalus, or Sphoeroides, or porcupinefish of the genus Diodon. Fugu can be lethally poisonous due to its tetrodotoxin; therefore, it must be carefully prepared to remove toxic parts and to...

 puffer that is not poisonous, and toxin level varies wildly even in fish that are. A puffer's neurotoxin is not necessarily as toxic to other animals as it is to humans, and puffers are eaten routinely by some species of fish, such as lizardfish and tiger shark
Tiger shark
The tiger sharks, Galeocerdo cuvier, is a species of requiem shark and the only member of the genus Galeocerdo. Commonly known as sea tigers, tiger sharks are relatively large macropredators, capable of attaining a length of over . It is found in many tropical and temperate waters, and is...

s. Also, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese fish farmers have grown nonpoisonous puffers by controlling their diet.

Puffers are able to move their eyes independently, and many species can change the color or intensity of their patterns in response to environmental changes. In these respects they are somewhat similar to the terrestrial chameleon
Chameleon
Chameleons are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a...

. Although most puffers are drab, many have bright colors and distinctive markings and make no attempt to hide from predators. This is likely an example of aposematism
Aposematism
Aposematism , perhaps most commonly known in the context of warning colouration, describes a family of antipredator adaptations where a warning signal is associated with the unprofitability of a prey item to potential predators...

.

Reproduction


Many marine puffers have a pelagic, or open-ocean, life stage. Spawning occurs after males slowly push females to the water surface or join females already present. The eggs are spherical and buoyant. Hatching occurs after roughly four days. The fry are tiny, but under magnification have a shape that is usually reminiscent of a puffer fish. They have a functional mouth and eyes, and must eat within a few days. Brackish water puffers may breed in bays in a similar manner to marine species, or may breed more similarly to the fresh water species, in cases where they have moved far enough upriver.

Reproduction in fresh water species varies quite a bit. The dwarf puffers court with males following females, possibly displaying the crests and keels unique to this subgroup of species. After the female accepts his advances, she will lead the male into plants, moss or another form of cover, where she can release eggs for fertilization. The male may help her by rubbing against her side. This has been observed in captivity, and they are the only commonly captive spawned puffer species.

Target-group puffers have also been spawned in aquariums, and follow a similar courting behavior, minus the crest/keel display. However, eggs are laid on a flat piece of slate or other smooth hard material, to which they adhere. The male will guard them until they hatch, carefully blowing water over them regularly to keep the eggs healthy. His parenting is finished when the young hatch, and the fry are on their own.

Information on breeding of specific species is very limited. T. Nigroviridis, the Green Spotted Puffer, has recently been artificially spawned under captive conditions. It is believed to spawn in bays in a similar manner to salt water species, as their sperm were found to be motile only at full marine salinities, but actual wild breeding has never been observed.

Evolution


The Tetraodontids have been estimated to diverge from diodontids between 89 and 138 million years ago. There are four major clades and these diverged during the Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 between 80 and 101 million years ago.

Poisoning


Pufferfish can be lethal if not served properly. Puffer poisoning usually results from consumption of incorrectly prepared puffer soup, fugu chiri, or occasionally from raw puffer meat, sashimi fugu
Fugu
is the Japanese word for pufferfish and the dish prepared from it, normally species of genus Takifugu, Lagocephalus, or Sphoeroides, or porcupinefish of the genus Diodon. Fugu can be lethally poisonous due to its tetrodotoxin; therefore, it must be carefully prepared to remove toxic parts and to...

. While chiri is much more likely to cause death, sashimi fugu often causes intoxication, light-headedness, and numbness of the lips, and is often eaten for this reason. Puffer's (tetrodotoxin
Tetrodotoxin
Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...

) poisoning deadens the tongue and lips, and induces dizziness and vomiting, followed by numbness and prickling over the body, rapid heart rate, decreased blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...

, and muscle paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

. The toxin paralyzes diaphragm
Thoracic diaphragm
In the anatomy of mammals, the thoracic diaphragm, or simply the diaphragm , is a sheet of internal skeletal muscle that extends across the bottom of the rib cage. The diaphragm separates the thoracic cavity from the abdominal cavity and performs an important function in respiration...

 muscles and stops the person who has ingested it from breathing. People who live longer than 24 hours typically survive, although possibly after a coma
Coma
In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...

 lasting several days. Some people claim to have remained fully conscious throughout the coma, and can often recount events that occurred while they were supposedly unconscious. The paralysis reduces oxygen demands of the body dramatically, but because the toxin does not cross the blood-brain barrier, neural activity in the brain and from the eyes and ears are generally intact. In Voodoo, puffer's poison must be part of the mixture given to the victim to make them a "zombie
Zombie
Zombie is a term used to denote an animated corpse brought back to life by mystical means such as witchcraft. The term is often figuratively applied to describe a hypnotized person bereft of consciousness and self-awareness, yet ambulant and able to respond to surrounding stimuli...

", most likely because the paralysis and pseudo-comatose effect simulate the death
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

 portion of traditional zombie creation.

It is not believed that puffers produce toxins themselves, as puffer fish kept in tanks or fish farms are totally free of either toxin. The gastric contents of shellfish prey are believed to carry the toxins or their precursors, which are stored in the puffers organs.

Saxitoxin
Saxitoxin
Saxitoxin is a neurotoxin naturally produced by certain species of marine dinoflagellates and cyanobacteria Saxitoxin (STX) is a neurotoxin naturally produced by certain species of marine dinoflagellates (Alexandrium sp., Gymnodinium sp., Pyrodinium sp.) and cyanobacteria Saxitoxin (STX) is a...

, the cause of paralytic shellfish poisoning
Paralytic shellfish poisoning
Paralytic shellfish poisoning is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks . These shellfish are filter feeders and, therefore, accumulate toxins produced by microscopic algae, such as...

 and red tide
Red tide
Red tide is a common name for a phenomenon also known as an algal bloom , an event in which estuarine, marine, or fresh water algae accumulate rapidly in the water column and results in discoloration of the surface water. It is usually found in coastal areas...

 can also be found in certain puffers.

Philippines


Locally Called the Butete only a few have mastered the art of making butete. Many people have died some thinking it is buriring a local pufferfish good for human consumption.

Thailand


Pufferfish, called pakpao in Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...

, are usually consumed by mistake. They are often cheaper than other fish, and because they contain inconsistent levels of toxins between fish and season, there is little awareness or monitoring of the danger. Consumers are regularly hospitalized and some even die from the poisoning.

Florida


Cases of neurological symptoms, including numbness and tingling of the lips and mouth, have been reported to rise after the consumption of puffers caught in the area of Titusville, Florida
Titusville, Florida
Titusville is a city in Brevard County, Florida in the United States. It is the county seat of Brevard County. Nicknamed Space City, USA, Titusville is on the Indian River, west of Merritt Island and the Kennedy Space Center and south-southwest of the Canaveral National Seashore...

. The symptoms generally resolve within hours to days, although one affected individual required intubation
Intubation
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic or rubber tube into the trachea to maintain an open airway or to serve as a conduit through which to administer certain drugs...

 for 72 hours. As a result, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

 banned the harvesting of puffers from certain bodies of water.

Poisoning treatment


Treatment consists of supportive care and intestinal decontamination with gastric lavage
Gastric lavage
Gastric lavage, also commonly called stomach pumping or Gastric irrigation, is the process of cleaning out the contents of the stomach. It has been used for over 200 years as a means of eliminating poisons from the stomach. Such devices are normally used on a person who has ingested a poison or...

 and activated charcoal. Case reports suggest that anticholinesterases such as edrophonium
Edrophonium
Edrophonium is a readily reversible acetylcholinesterase inhibitor. It prevents breakdown of the neurotransmitter acetylcholine and acts by competitively inhibiting the enzyme acetylcholinesterase, mainly at the neuromuscular junction...

 may be effective.

See also

  • Fugu
    Fugu
    is the Japanese word for pufferfish and the dish prepared from it, normally species of genus Takifugu, Lagocephalus, or Sphoeroides, or porcupinefish of the genus Diodon. Fugu can be lethally poisonous due to its tetrodotoxin; therefore, it must be carefully prepared to remove toxic parts and to...

    , the Japanese dish containing puffers meat, famous for its potent toxicity
    Tetrodotoxin
    Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...

  • Neurotoxin
    Neurotoxin
    A neurotoxin is a toxin that acts specifically on nerve cells , usually by interacting with membrane proteins such as ion channels. Some sources are more general, and define the effect of neurotoxins as occurring at nerve tissue...

  • Tetrodotoxin
    Tetrodotoxin
    Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...

  • Shimonoseki
    Shimonoseki, Yamaguchi
    is a city located in Yamaguchi Prefecture, Japan. It is at the southwestern tip of Honshū, facing the Tsushima Strait and also Kitakyushu across the Kanmon Straits....


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