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Centipede (Kaki seratus)Scientific classification Kingdom: AnimaliaPhylum: ArthropodaSubphylum: MyriapodaClass: ChilopodaLatreille, 1817
Centipedes (from Latin prefix centi-, "hundred", and pes, pedis, "foot") are arthropods belonging to the class Chilopoda of the subphylum Myriapoda, an arthropod group which also includes Millipedes and other multi-legged creatures. Centipedes are elongated metameric creatures with one pair of legs per body segment. Centipedes are known to be highly venomous, and often inject paralyzing venom. Despite the name, centipedes can have a varying number of legs, ranging from 30 to 354. Centipedes always have an odd number of pairs of legs. Therefore, no centipede has exactly 100 legs. A key trait uniting this group is a pair of venom claws or forcipules formed from a modified first appendage. Centipedes are predominantly carnivorous.
Their size can range from a few millimetres in the smaller lithobiomorphs and geophilomorphs to about 30 cm (12 in) in the largest scolopendromorphs. Centipedes can be found in a wide variety of environments. They normally have a drab coloration combining shades of brown and red. Cavernicolous (cave-dwelling) and subterranean species may lack pigmentation, and many tropical scolopendromorphs have bright aposematic colours.
Worldwide, an estimated 8,000 species of centipedes are thought to exist, of which 3,000 have been described. Centipedes have a wide geographical range, where they even reach beyond the Arctic Circle. They are found in an array of terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, therefore causing them to rapidly lose water.Ac cordingly, they are found in soil and leaf litter, under stones and dead wood, and inside logs. Centipedes are among the largest terrestrial invertebrate predators, and often contribute significantly to the invertebrate predatory biomass in terrestrial ecosystems. Only one species, Scolopendra cataracta, is known to be amphibious and is believed to hunt aquatic or amphibious invertebrates
DescriptionCentipedes have a rounded or flattened head, bearing a pair of antennae at the forward margin. They have a pair of elongated mandibles, and two pairs of maxillae. The first pair of maxillae form the lower lip, and bear short palps. The first pair of limbs stretch forward from the body to cover the remainder of the mouth. These limbs, or maxillipeds, end in sharp claws and include venom glands that help the animal to kill or paralyze its prey.Many species of centipedes lack eyes, but some possess a variable number of ocelli, which are sometimes clustered together to form true compound eyes. However, these eyes are only capable of discerning light and dark, and have no true vision. In some species, the first pair of legs at the head end of the centipede acts as sense organs similar to antennae, but unlike the antennae of most other animals, theirs point backwards. Unusual sense organs found in some groups are the organs of Tömösváry. These are located at the base of the antennae, and consist of a disc-like structure with a central pore surrounded by sensory cells. They are probably used for sensing vibrations, and may even provide a sense of hearing.Forcipules are a unique feature found only in centipedes and in no other arthropods. The forcipules are modifications of the first pair of legs, forming a pincer-like appendage always found just behind the head.[8] Forcipules are not true mouthparts, although they are used in the capture of prey items, injecting venom and holding onto captured prey. Venom glands run through a tube almost to the tip of each forcipule.Behind the head, the body consists of 15 or more segments. Most of the segments bear a single pair of legs, with the maxillipeds projecting forward from the first body segment, and the final two segments being small and legless. Each pair of legs is slightly longer than the pair immediately in front of it, ensuring that they do not overlap, so reducing the chance that they will collide with each other while moving swiftly. In extreme cases, the last pair of legs may be twice the length of the first pair. The final segment bears a telson and includes the openings of the reproductive organs.As predators, centipedes mainly use their antennae to seek out their prey. The digestive tract forms a simple tube, with digestive glands attached to the mouthparts. Like insects, centipedes breathe through a tracheal system, typically with a single opening, or spiracle on each body segment. They excrete waste through a single pair of malpighian tubules.Scolopendra gigantea, also known as the Amazonian giant centipede, is the largest existing species of centipede in the world, reaching over 30 cm (12 in) in length. It is known to eat lizards, frogs, birds, mice, and even bats, catching them in midflight, as well as rodents and spiders.
LifecycleCentipede reproduction does not involve copulation. Males deposit a spermatophore for the female to take up. In one clade, this spermatophore is deposited in a web, and the male undertakes a courtship dance to encourage the female to engulf his sperm. In other cases, the males just leave them for the females to find. In temperate areas, egg laying occurs in spring and summer, but in subtropical and tropical areas, little seasonality to centipede breeding is apparent. A few species of parthenogenetic centipedes are known.The Lithobiomorpha and Scutigeromorpha lay their eggs singly in holes in the soil, and the female fills the holes with soil and leaves them. The number of eggs laid ranges from about 10 to 50. Time of development of the embryo to hatching is highly variable and may take from one to a few months. Time of development to reproductive period is highly variable within and among species. For example, it can take 3 years for S. coleoptrata to achieve adulthood, whereas under the right conditions, lithobiomorph species may reach a reproductive period in 1 year. In addition, centipedes are relatively long-lived when compared to insects. For example, the European Lithobius forficatus may live for 5 to 6 years,[10] and the wide-ranging Scolopendra subspinipes can live for over 10 years. The combination of a small number of eggs laid, long gestation period, and long time of development to reproduction has led authors to label lithobiomorph centipedes as K-selected.Females of the Geophilomorpha and Scolopendromorpha show far more parental care. The eggs, 15 to 60 in number, are laid in a nest in the soil or in rotten wood. The female stays with the eggs, guarding and licking them to protect them from fungi. The female in some species stays with the young after they have hatched, guarding them until they are ready to leave. If disturbed, the female either abandons the eggs or eats them; abandoned eggs tend to fall prey to fungi rapidly. Some species of Scolopendromorpha are matriphagic, meaning the offspring eat their mother.
EcologyCentipedes are predominantly generalist predators, which means they have adapted to eat a variety of different available prey. Examination of centipede gut contents suggests that plant material is an unimportant part of their diets, although centipedes have been observed to eat vegetable matter when starved during laboratory experiments.Centipedes are mostly nocturnal. Studies on their activity rhythms confirm this, although a few observations of centipedes active during the day have been made, and one species, Strigamia chinophila, is diurnal. What centipedes actually eat is not well known because of their cryptic lifestyles and thorough mastication of food. Laboratory feeding trials support that they will feed as generalists, taking almost anything that is soft-bodied and in a reasonable size range. Earthworms may provide the bulk of diets for geophilomorphs, since they burrow through the soil and earthworm bodies would be easily pierced by their venom claws. Geophilomorphs probably cannot subdue earthworms larger than themselves, so smaller earthworms may be a substantial proportion of their diet.Scolopendromorphs, given their size, are able to feed on vertebrates, in addition to invertebrates. They have been observed eating reptiles, amphibians, small mammals, bats, and birds. Springtails may provide a large proportion of lithobiomorph diets. Little is known about scutigeromorph or craterostigmomorph diets. All centipedes are potential intraguild predators. Centipedes and spiders may frequently prey on one another.Many larger animals prey upon centipedes, such as mongooses, mice, salamanders, beetles and snakes. They form an important item of diet for many species and the staple diet of some such as the African ant Amblyopone pluto, which feeds solely on geophilomorph centipedes, and the South African Cape black-headed snake Aparallactus capensis.Centipede defences include their speed and venomous forcipules, as well as the secretion of defensive chemicals. Geophilomorph centipedes can secrete sticky substances that generate toxic hydrogen cyanide and benzoic acid from microscopic glands on their undersides. Similarly, lithobiomorph centipedes secrete a sticky substance from glands in the rear-most two pairs of legs.Water regulation is an important aspect of centipede ecology, since they lose water rapidly in dry conditions and are found in moist microhabitats. Water loss is a result of centipedes lacking a waxy covering of their exoskeleton and excreting waste nitrogen as ammonia, which requires extra water. Centipedes deal with water loss through a variety of adaptations. Geophilomorphs lose water less rapidly than lithobiomorphs, though they have a greater surface area to volume ratio. This may be because geophilomorphs have a more heavily sclerotized pleural membrane. Spiracle shape, size, and ability to constrict also have an influence on rate of water loss. In addition, the number and size of coxal pores may be variables affecting centipede water balance.Centipedes live in many different habitat types—forest, savannah, prairie, and desert, to name a few. Some geophilomorphs are adapted to littoral habitats, where they feed on barnacles. Species of all orders excluding the Craterostigmomorpha have adapted to caves. Centipede densities have been recorded as high as 600/m2 and biomass as high as 500 mg/m2 wet weight. Small geophilomorphs attain highest densities, followed by small lithobiomorphs. Large lithobiomorphs attain densities of 20/m2. One study of scolopendromorphs records Scolopendra morsitans in a Nigerian savannah at a density of 0.16/m2 and a biomass of 140 mg/m2 wet weigh
UsesAs foodAs a food item, certain large-sized centipedes are consumed in China, usually skewered and grilled or deep fried. They are often seen in street vendor's stalls in large cities, including Donghuamen and Wangfujing markets in Beijing.Also in China, as well as in Laos, Thailand, and Cambodia, large centipedes are kept in liquor for a period of time. This custom is allegedly part of the traditional Chinese medicine. Said to have medicinal properties and to be reinvigorating,[20] the liquor with the centipede submerged in it is consumed as a special drink.
Hazards to humansSome species of centipedes can be hazardous to humans because of their bite. Although a bite to an adult human is usually very painful and may cause severe swelling, chills, fever, and weakness, it is unlikely to be fatal. Bites can be dangerous to small children and those with allergies to bee stings. The venomous bite of larger centipedes can induce anaphylactic shock in such people. Smaller centipedes are generally incapable of piercing human skin.Even nonvenomous centipedes are considered frightening by humans due to their dozens of legs moving at the same time and their tendency to dart swiftly out of the darkness towards one's feet.[23] A 19th-century Tibetan poet warned his fellow Buddhists, "if you enjoy frightening others, you will be reborn as a centipede
Centipedes (from Latin prefix centi-, "hundred", and pes, pedis, "foot") are arthropods belonging to the class Chilopoda of the subphylum Myriapoda, an arthropod group which also includes Millipedes and other multi-legged creatures. Centipedes are elongated metameric creatures with one pair of legs per body segment. Centipedes are known to be highly venomous, and often inject paralyzing venom. Despite the name, centipedes can have a varying number of legs, ranging from 30 to 354. Centipedes always have an odd number of pairs of legs. Therefore, no centipede has exactly 100 legs. A key trait uniting this group is a pair of venom claws or forcipules formed from a modified first appendage. Centipedes are predominantly carnivorous.
Their size can range from a few millimetres in the smaller lithobiomorphs and geophilomorphs to about 30 cm (12 in) in the largest scolopendromorphs. Centipedes can be found in a wide variety of environments. They normally have a drab coloration combining shades of brown and red. Cavernicolous (cave-dwelling) and subterranean species may lack pigmentation, and many tropical scolopendromorphs have bright aposematic colours.
Worldwide, an estimated 8,000 species of centipedes are thought to exist, of which 3,000 have been described. Centipedes have a wide geographical range, where they even reach beyond the Arctic Circle. They are found in an array of terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, therefore causing them to rapidly lose water.Ac cordingly, they are found in soil and leaf litter, under stones and dead wood, and inside logs. Centipedes are among the largest terrestrial invertebrate predators, and often contribute significantly to the invertebrate predatory biomass in terrestrial ecosystems. Only one species, Scolopendra cataracta, is known to be amphibious and is believed to hunt aquatic or amphibious invertebrates
DescriptionCentipedes have a rounded or flattened head, bearing a pair of antennae at the forward margin. They have a pair of elongated mandibles, and two pairs of maxillae. The first pair of maxillae form the lower lip, and bear short palps. The first pair of limbs stretch forward from the body to cover the remainder of the mouth. These limbs, or maxillipeds, end in sharp claws and include venom glands that help the animal to kill or paralyze its prey.Many species of centipedes lack eyes, but some possess a variable number of ocelli, which are sometimes clustered together to form true compound eyes. However, these eyes are only capable of discerning light and dark, and have no true vision. In some species, the first pair of legs at the head end of the centipede acts as sense organs similar to antennae, but unlike the antennae of most other animals, theirs point backwards. Unusual sense organs found in some groups are the organs of Tömösváry. These are located at the base of the antennae, and consist of a disc-like structure with a central pore surrounded by sensory cells. They are probably used for sensing vibrations, and may even provide a sense of hearing.Forcipules are a unique feature found only in centipedes and in no other arthropods. The forcipules are modifications of the first pair of legs, forming a pincer-like appendage always found just behind the head.[8] Forcipules are not true mouthparts, although they are used in the capture of prey items, injecting venom and holding onto captured prey. Venom glands run through a tube almost to the tip of each forcipule.Behind the head, the body consists of 15 or more segments. Most of the segments bear a single pair of legs, with the maxillipeds projecting forward from the first body segment, and the final two segments being small and legless. Each pair of legs is slightly longer than the pair immediately in front of it, ensuring that they do not overlap, so reducing the chance that they will collide with each other while moving swiftly. In extreme cases, the last pair of legs may be twice the length of the first pair. The final segment bears a telson and includes the openings of the reproductive organs.As predators, centipedes mainly use their antennae to seek out their prey. The digestive tract forms a simple tube, with digestive glands attached to the mouthparts. Like insects, centipedes breathe through a tracheal system, typically with a single opening, or spiracle on each body segment. They excrete waste through a single pair of malpighian tubules.Scolopendra gigantea, also known as the Amazonian giant centipede, is the largest existing species of centipede in the world, reaching over 30 cm (12 in) in length. It is known to eat lizards, frogs, birds, mice, and even bats, catching them in midflight, as well as rodents and spiders.
LifecycleCentipede reproduction does not involve copulation. Males deposit a spermatophore for the female to take up. In one clade, this spermatophore is deposited in a web, and the male undertakes a courtship dance to encourage the female to engulf his sperm. In other cases, the males just leave them for the females to find. In temperate areas, egg laying occurs in spring and summer, but in subtropical and tropical areas, little seasonality to centipede breeding is apparent. A few species of parthenogenetic centipedes are known.The Lithobiomorpha and Scutigeromorpha lay their eggs singly in holes in the soil, and the female fills the holes with soil and leaves them. The number of eggs laid ranges from about 10 to 50. Time of development of the embryo to hatching is highly variable and may take from one to a few months. Time of development to reproductive period is highly variable within and among species. For example, it can take 3 years for S. coleoptrata to achieve adulthood, whereas under the right conditions, lithobiomorph species may reach a reproductive period in 1 year. In addition, centipedes are relatively long-lived when compared to insects. For example, the European Lithobius forficatus may live for 5 to 6 years,[10] and the wide-ranging Scolopendra subspinipes can live for over 10 years. The combination of a small number of eggs laid, long gestation period, and long time of development to reproduction has led authors to label lithobiomorph centipedes as K-selected.Females of the Geophilomorpha and Scolopendromorpha show far more parental care. The eggs, 15 to 60 in number, are laid in a nest in the soil or in rotten wood. The female stays with the eggs, guarding and licking them to protect them from fungi. The female in some species stays with the young after they have hatched, guarding them until they are ready to leave. If disturbed, the female either abandons the eggs or eats them; abandoned eggs tend to fall prey to fungi rapidly. Some species of Scolopendromorpha are matriphagic, meaning the offspring eat their mother.
EcologyCentipedes are predominantly generalist predators, which means they have adapted to eat a variety of different available prey. Examination of centipede gut contents suggests that plant material is an unimportant part of their diets, although centipedes have been observed to eat vegetable matter when starved during laboratory experiments.Centipedes are mostly nocturnal. Studies on their activity rhythms confirm this, although a few observations of centipedes active during the day have been made, and one species, Strigamia chinophila, is diurnal. What centipedes actually eat is not well known because of their cryptic lifestyles and thorough mastication of food. Laboratory feeding trials support that they will feed as generalists, taking almost anything that is soft-bodied and in a reasonable size range. Earthworms may provide the bulk of diets for geophilomorphs, since they burrow through the soil and earthworm bodies would be easily pierced by their venom claws. Geophilomorphs probably cannot subdue earthworms larger than themselves, so smaller earthworms may be a substantial proportion of their diet.Scolopendromorphs, given their size, are able to feed on vertebrates, in addition to invertebrates. They have been observed eating reptiles, amphibians, small mammals, bats, and birds. Springtails may provide a large proportion of lithobiomorph diets. Little is known about scutigeromorph or craterostigmomorph diets. All centipedes are potential intraguild predators. Centipedes and spiders may frequently prey on one another.Many larger animals prey upon centipedes, such as mongooses, mice, salamanders, beetles and snakes. They form an important item of diet for many species and the staple diet of some such as the African ant Amblyopone pluto, which feeds solely on geophilomorph centipedes, and the South African Cape black-headed snake Aparallactus capensis.Centipede defences include their speed and venomous forcipules, as well as the secretion of defensive chemicals. Geophilomorph centipedes can secrete sticky substances that generate toxic hydrogen cyanide and benzoic acid from microscopic glands on their undersides. Similarly, lithobiomorph centipedes secrete a sticky substance from glands in the rear-most two pairs of legs.Water regulation is an important aspect of centipede ecology, since they lose water rapidly in dry conditions and are found in moist microhabitats. Water loss is a result of centipedes lacking a waxy covering of their exoskeleton and excreting waste nitrogen as ammonia, which requires extra water. Centipedes deal with water loss through a variety of adaptations. Geophilomorphs lose water less rapidly than lithobiomorphs, though they have a greater surface area to volume ratio. This may be because geophilomorphs have a more heavily sclerotized pleural membrane. Spiracle shape, size, and ability to constrict also have an influence on rate of water loss. In addition, the number and size of coxal pores may be variables affecting centipede water balance.Centipedes live in many different habitat types—forest, savannah, prairie, and desert, to name a few. Some geophilomorphs are adapted to littoral habitats, where they feed on barnacles. Species of all orders excluding the Craterostigmomorpha have adapted to caves. Centipede densities have been recorded as high as 600/m2 and biomass as high as 500 mg/m2 wet weight. Small geophilomorphs attain highest densities, followed by small lithobiomorphs. Large lithobiomorphs attain densities of 20/m2. One study of scolopendromorphs records Scolopendra morsitans in a Nigerian savannah at a density of 0.16/m2 and a biomass of 140 mg/m2 wet weigh
UsesAs foodAs a food item, certain large-sized centipedes are consumed in China, usually skewered and grilled or deep fried. They are often seen in street vendor's stalls in large cities, including Donghuamen and Wangfujing markets in Beijing.Also in China, as well as in Laos, Thailand, and Cambodia, large centipedes are kept in liquor for a period of time. This custom is allegedly part of the traditional Chinese medicine. Said to have medicinal properties and to be reinvigorating,[20] the liquor with the centipede submerged in it is consumed as a special drink.
Hazards to humansSome species of centipedes can be hazardous to humans because of their bite. Although a bite to an adult human is usually very painful and may cause severe swelling, chills, fever, and weakness, it is unlikely to be fatal. Bites can be dangerous to small children and those with allergies to bee stings. The venomous bite of larger centipedes can induce anaphylactic shock in such people. Smaller centipedes are generally incapable of piercing human skin.Even nonvenomous centipedes are considered frightening by humans due to their dozens of legs moving at the same time and their tendency to dart swiftly out of the darkness towards one's feet.[23] A 19th-century Tibetan poet warned his fellow Buddhists, "if you enjoy frightening others, you will be reborn as a centipede
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