Spiders
an Orb weaver spider, Family: Araneidae
Scientific classification
Kingdom: Animalia Phylum: Arthropoda Class: Arachnida Order: Araneae Clerck, 1757
Diversity
111 families, 40,000 species
Suborders
Mesothelae Mygalomorphae Araneomorphae  See table of families

Spiders are predatory invertebrate animals that have two body segments, eight legs, no chewing mouth parts and no wings. The orb-weaver spiders (family Araneidae) are the builders of spiral wheel-shaped webs often found in gardens fields and forests The orb-weaver spiders (family Araneidae) are the builders of spiral wheel-shaped webs often found in gardens fields and forests Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " Arachnids are a class ( Arachnida) of joint-legged Invertebrate Animals in the subphylum Chelicerata. Carl Alexander Clerck ( 1709 - 22 July 1765) was a Swedish Entomologist and arachnologist. Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod An invertebrate is an Animal lacking a Vertebral column. The group includes 98% of all animal Species — all animals except those in the Chordate In Invertebrate Biology, a tagma (plural tagmata) is a specialized grouping of Arthropodan segments such as the They are classified in the order Araneae, one of several orders within the larger class of arachnids, a group that also contains scorpions, whip scorpions, mites, ticks, and opiliones (harvestmen). This article is about the taxonomic rank for the sequence of species in a taxonomic list see Taxonomic order In scientific classification used Arachnids are a class ( Arachnida) of joint-legged Invertebrate Animals in the subphylum Chelicerata. Scorpions are eight-legged Carnivorous Arthropods They are members of the order Scorpiones within the class Arachnida. A uropygid, commonly known as a whip scorpion, is an invertebrate animal belonging to the former order "Uropygi" in the class Arachnida, Mites, along with Ticks belong to the subclass Acarina (also known as Acari and the class Arachnida Mites are among the most diverse and successful Tick is the common name for the small Arachnids in Superfamily Ixodoidea that along with other Mites constitute the Acarina. Harvestmen are eight-legged Invertebrate animals belonging to the order Opiliones (formerly Phalangida) in the class Arachnida in the subphylum The study of spiders is called araneology.

All spiders produce silk, a thin, strong protein strand extruded by the spider from spinnerets most commonly found on the end of the abdomen. Spider silk, also known as Gossamer, is a Protein Fiber spun by Spiders Spiders use their silk to make webs or other structures which function Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl A spinneret is a spider's silk -spinning organ. It is usually on the underside of a spider's Abdomen, to the rear Many species use it to trap insects in webs, although there are also many species that hunt freely. Silk can be used to aid in climbing, form smooth walls for burrows, build egg sacs, wrap prey, and temporarily hold sperm, among other applications.

All spiders except those in the families Uloboridae and Holarchaeidae, and in the suborder Mesothelae (together about 350 species) can inject venom to protect themselves or to kill prey. The hackled orbweavers (family Uloboridae) have the special distinction of being non- venomous Spiders Their lack of poison glands is a secondary evolved The Holarchaeidae are a Spider family with only two described species in one genus The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant This article is about the class of Biotoxins For other uses see Venom (disambiguation and Venomous (disambiguation. Only about 200 species, however, have bites that can pose health problems to humans. '''Spiders''' occasionally bite humans Although 98-99% of spider bites are harmless more rarely the symptoms of their bites can include necrotic wounds systemic ^[1] Many larger species' bites may be quite painful, but will not produce lasting health concerns.

Spiders are found all over the world, from the tropics to the Arctic, living underwater in silken domes they supply with air, and on the tops of mountains. In 1973 Skylab 3 took two spiders into space to test their web-spinning capabilities in zero gravity. Skylab 3 (also SL-3 and SLM-2) was the second manned mission to Skylab. Space is the extent within which Matter is physically extended and objects and Events have positions relative to one another

Contents 1 Morphology 1.1 Prosoma 1.2 Sense organs 1.3 Respiration and circulation 1.4 Digestion 1.5 Spinnerets 1.6 Size 1.7 Coloration 1.8 Life cycle 1.9 Lifespan 1.10 Reproduction 1.11 Sacrificial males 2 Ecology 3 Behavior 3.1 Predatory techniques 3.1.1 Spider webs 3.1.2 Hunting spiders 3.1.3 Ambush predators 3.2 Defense 3.3 Social spiders 4 Web types 4.1 Tangleweb spiders 4.2 Orb web spiders 4.3 Other types of webs 5 Evolution 6 Taxonomy 6.1 Mesothelae 6.2 Mygalomorphae 6.3 Araneomorphae 6.4 Creatures often mistaken for spiders 7 Spiders and people 7.1 Spider bites 7.2 Spiders as food 7.3 Arachnophobia 7.4 Spiders in symbolism and culture 8 See also 9 Footnotes 10 References 11 External links 11.1 General 11.2 Regional 11.3 Morphology 11.4 Taxonomy 11.5 Pictures 11.6 Other

Morphology

Spiders, unlike insects, have only two body segments (tagmata) instead of three: a fused head and thorax (called a cephalothorax or prosoma) and an abdomen (called the opisthosoma). The arthropod leg is a form of jointed Appendage of Arthropods usually used for Walking. Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described In Invertebrate Biology, a tagma (plural tagmata) is a specialized grouping of Arthropodan segments such as the In Anatomy, the head of an Animal is the Rostral part (from Anatomical position that usually comprises the Brain, Eyes The thorax is a division of an Animal 's body that lies between the head and the Abdomen. The cephalothorax (call prosoma in some groups is an anatomical term used in Arachnids and Malacostracan Crustaceans for the The cephalothorax (call prosoma in some groups is an anatomical term used in Arachnids and Malacostracan Crustaceans for the In Vertebrates such as Mammals the abdomen (belly constitutes the part of the body between the Thorax (chest and Pelvis. The opisthosoma is the posterior portion of the Arachnids body behind the Prosoma (cephalothorax The exception to this rule are the assassin spiders, whose cephalothorax seems to be almost divided into two independent units. The Archaeidae are a Spider family with 25 described species in three genera Except for a few species of very primitive spiders (family Liphistiidae), the abdomen is not externally segmented. The spider family Liphistiidae comprises 5 genera and 85 Species from Southeast Asia, China, and Japan. The abdomen and cephalothorax are connected with a thin waist called the pedicle or the pregenital somite, a trait that allows the spider to move the abdomen in all directions. This waist is actually the last segment (somite) of the cephalothorax and is lost in most other members of the Arachnida (in scorpions it is only detectable in the embryos).

Prosoma

All spiders have eight legs, although a few ant-mimicking species use their front legs to imitate antennae, which spiders lack. Ant mimicry is Mimicry of Ants by other organisms Ants are abundant all over the world and insect Predators that rely on vision to identify their prey such Antennae (singular antenna) are paired Appendages connected to the front-most segments of Arthropods In Crustaceans they are Their eyes are single lenses rather than compound eyes, ranging from simple light/dark-receptors to eyes rivaling those of a pigeon (some jumping spiders). A lens is an optical device with perfect or approximate Axial symmetry which transmits and refracts Light, converging or diverging

They have pedipalps (or just palps), at the base of which are coxae or maxillae next to their mouth that aid in ingesting food; the ends of the palp are modified in adult males into elaborate and often species-specific structures used for mating. Pedipalps, are the second pair of Appendages of the Prosoma in the subphylum Chelicerata. This article is about the Mammal maxilla For Arthropod maxillae see Mouthparts; for Insect maxillae in particular see Insect mouthparts Since they have no antennae, they use specialised and sensitive hairs on their legs to pick up scent, sounds, vibrations and air currents.

Sense organs

Spiders usually have eight eyes in various arrangements, a fact that is used to aid in taxonomically classifying different species. Taxonomy is the practice and science of classification The word comes from the Greek, taxis (meaning 'order' 'arrangement' and, nomos Most species of the Haplogynae have six eyes, although some have eight (Plectreuridae), four (eg. The Haplogynae are a series of araneomorph spiders Unlike the Entelegynae, they lack hardened (sclerotized female genitalia ( Epigynes Plectreurid spiders (family Plectreuridae) belong to a small family confined to the North American Deserts and the island of Cuba. , Tetrablemma) or even two (most Caponiidae) eyes. The spider genus Tetrablemma is unusual in possessing only four eyes a trait only found elsewhere in most species of the family Caponiidae. Spiders of the Ecribellate Haplogyne family Caponiidae are unusual in that most species have only two eyes which is unheard of in other spiders Sometimes one pair of eyes is better developed than the rest, or even, in some cave species, there are no eyes at all. As with other animals there are some species of cave-dwelling spiders that have lost their ability to see Several families of hunting spiders, such as jumping spiders and wolf spiders, have fair to excellent vision. The jumping spider family ( Salticidae) contains more than 500 described genera and over 5000 Species, making it the largest family of Spiders with about The main pair of eyes in jumping spiders even see in color.

Net-casting spiders have enormous, compound lenses that give a wide field of view and gather available light very efficiently. The Spider family Deinopidae consists of stick-like elongate spiders that build unusual webs that they suspend between the front legs

However, most spiders that lurk on flowers, webs, and other fixed locations waiting for prey tend to have very poor eyesight; instead they possess an extreme sensitivity to vibrations, which aids in prey capture. Vibration sensitive spiders can sense vibrations from such various mediums as the water surface, the soil or their silk threads. Also changes in the air pressure can be detected in the search for prey.

Respiration and circulation

Spiders have an open circulatory system; i. The epigyne or epigynum is the female genital opening in Spiders It is of special interest to people who study spiders because the exact shape of the epigyne This is an article about the rock music band "Circulatory System" e. , they do not have true blood, or veins to convey it. Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products In the Circulatory system, a vein is a Blood vessel that carries Blood back toward the Heart (as opposed to Artery, a blood vessel Rather, their bodies are filled with haemolymph, which is pumped through arteries by a heart into spaces called sinuses surrounding their internal organs. Hemolymph or haemolymph is the Blood analogue used by all Arthropods and most Mollusks that have an Open circulatory system. The heart is a muscular organ in all Vertebrates responsible for pumping Blood through the Blood vessels by repeated rhythmic Sinus is Latin for "bay" "pocket" "curve" or "bosom" In Biology, an organ ( Latin: organum, "instrument tool" from Greek όργανον - organon "organ instrument

Spiders have developed several different respiratory anatomies, based either on book lungs, a tracheal system, or both. A book lung is a type of Respiration organ used for atmospheric gas exchange and is found in Arachnids such as Scorpions and Spiders Each of these Many terrestrial Arthropods have evolved a closed Respiratory system composed of Spiracles, tracheae and Tracheoles to transport metabolic Mygalomorph and Mesothelae spiders have two pairs of book lungs filled with haemolymph, where openings on the ventral surface of the abdomen allow air to enter and diffuse oxygen. The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant A book lung is a type of Respiration organ used for atmospheric gas exchange and is found in Arachnids such as Scorpions and Spiders Each of these In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the This is also the case for some basal araneomorph spiders like the family Hypochilidae, but the remaining members of this group have just the anterior pair of book lungs intact while the posterior pair of breathing organs are partly or fully modified into tracheae, through which oxygen is diffused into the haemolymph or directly to the tissue and organs. The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action The Lampshade spiders of the family Hypochilidae are among the most primitive of Araneomorph Spiders There are two genera and eleven This system has most likely evolved in small ancestors to help resist desiccation. Desiccation is the state of extreme dryness or the process of extreme drying The trachea were originally connected to the surroundings through a pair of spiracles, but in the majority of spiders this pair of spiracles has fused into a single one in the middle, and migrated posterior close to the spinnerets.

Among smaller araneomorph spiders we can find species who have evolved also the anterior pair of book lungs into trachea, or the remaining book lungs are simply reduced or missing, and in a very few the book lungs have developed deep channels, apparently signs of evolution into tracheae. Some very small spiders in moist and sheltered habitats have no breathing organs at all, and instead breathe directly through their body surface. In the tracheal system, oxygen interchange is much more efficient, enabling cursorial hunting (hunting involving extended pursuit) and other advanced characteristics as having a smaller heart and the ability to live in drier habitats. Cursorial hunting is a hunting strategy practised by animals that are much slower over short distances than their quarry but have superior endurance over long distances

Digestion

Spiders can only eat their food in liquid form. For this purpose predigestion is carried out both internally and externally to liquefy the tissues of their prey. Some spiders do this by spitting up digestive juices onto prey while chewing it with their chelicerae. The resulting liquefied "soup" is then sucked up by the spider. Dense combs of hairs around the mouth filter out solids while the spider ingests the liquids. Undigested or uneaten parts of the prey are later discarded. Some spiders do not chew their food, but inject digestive fluids from their stomachs directly into the body of the prey to liquefy the inner tissues and organs. The spider then sucks out the liquefied tissues, eventually leaving the empty outer exoskeleton of the prey.

Many spiders will store prey temporarily. Web-building spiders that have made a shroud of silk to quiet their envenomed prey's death struggles will often leave them in these shrouds and then consume them later.

Spiders are capable of digesting their own silk, so some spiders may eat their used webs. When a spider drops down on a single strand of silk and then returns, it will generally rapidly consume the strand of silk on its way back up.

Spinnerets

The abdomen has no appendages except from one to four (usually three) modified pairs of movable telescoping organs called spinnerets, which produce silk. A spinneret is a spider's silk -spinning organ. It is usually on the underside of a spider's Abdomen, to the rear Spider silk, also known as Gossamer, is a Protein Fiber spun by Spiders Spiders use their silk to make webs or other structures which function The suborder Mesothelae is unique in having only two types of silk glands — thought to be the ancestral condition. All other spiders have the spinnerets further towards the posterior end of the body where they form a small cluster, and the anterior central spinnerets on the tenth segment are lost or reduced (suborder Mygalomorphae), or modified into a specialised and flattened plate called the cribellum (parts of suborder Araneomorphae), which produces a thread made up of hundreds to thousands of very fine dry silk fibers resulting in a woolly structure that traps prey. The cribellate spiders were the first spiders to build specialized prey catching webs. Later some groups evolved (called ecribellate) that use silk threads dotted with sticky droplets to capture prey ranging from small arthropods to sometimes even small bats and birds.

Size

Spiders occur in a large range of sizes. The smallest, dwarf spiders of the subfamily Erigoninae, are less than 1 mm (about . 05 inches) in body length. The largest and heaviest spiders occur among tarantulas, which can have body lengths up to 90 mm (about 3. Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species 5 inches) and leg spans up to 250 mm (about 10 inches). ^[2]

Coloration

Only three classes of pigment (ommochromes, bilins and guanine) have been identified in spiders, although other pigments have been detected but not yet characterized. For the drug referred to as "pigment" see Black tar heroin. Ommochrome (or visual pigment) refers to several biological Pigments that occur in the Eyes of Crustaceans and Insects The Bilins or bilanes are biological pigments formed in many organisms as a metabolic product of certain Porphyrins Bilin (also called bilichrome was named as a Guanine is one of the five main Nucleobases found in the Nucleic acids DNA and RNA, the others being Adenine, Cytosine, Melanins, carotenoids and pterins, very common in other animals, are apparently absent. Melanin is a class of compounds found in the Plant, Animal and Protista kingdoms, where it serves predominantly as a Pigment. Carotenoids are organic Pigments that are naturally occurring in Chromoplasts of plants and some other photosynthetic Organisms Pterin is a heterocyclic compound composed of a Pyrazine ring and a Pyrimidine ring (a Pteridine ring system the pyrimidine ring has a In some species the exocuticle of the legs and prosoma is modified by a tanning process, resulting in brown coloration. The procuticle is the major portion of the Exoskeleton of an Insect (and various other Arthropods; its exact composition and structure may differ somewhat Tanning is the process of converting Putrescible skin into non-putrescible Leather, usually with Tannin, an Acidic Chemical compound ^[3] Bilins are found for example in Micrommata virescens, resulting in its green color. The green huntsman spider ( Micrommata virescens) is a spider of the family Sparassidae. Guanine is responsible for the white markings of the European garden spider Araneus diadematus. The European garden spider ( Araneus diadematus) or diadem spider, also called the cross spider in Eastern Europe, is a very common and well-known It is in many species accumulated in specialized cells called guanocytes. In genera such as Tetragnatha, Leucauge, Argyrodes or Theridiosoma, guanine creates their silvery appearance. Tetragnatha is a Genus of Spiders containing hundreds of species Leucauge is a spider genus with Pantropical distribution The body and leg shapes and the silver black and yellow markings of Leucauge females Spiders of the genus Argyrodes ( Theridiidae) also called dewdrop spiders, occur worldwide The ray spiders (family Theridiosomatidae) are Spiders most recognizable for their construction of cone-shaped webs While guanine is originally an end-product of protein metabolism, its excretion can be blocked in spiders, leading to an increase in its storage. ^[3]

Structural colors occur in some species, which are the result of the diffraction, scattering or interference of light, for example by modified setae or scales. Seta (plural setae) is a biological term derived from the Latin word for " Bristle " The white prosoma of Argiope results from hairs reflecting the light, Lycosa and Josa both have areas of modified cuticle that act as light reflectors. The Genus Argiope includes rather large and spectacular Spiders that have often a strikingly coloured Abdomen. Lycosa is a genus of Wolf spiders The more than 200 species are found throughout most of the world Josa is a municipality located in the province of Teruel, Aragon, Spain. ^[3]

Life cycle

The spider life cycle progresses through three stages: the embryonic, the larval, and the nympho-imaginal. An embryo (from Greek:, plural, lit "that which grows" from en- "in" + bryein "to swell be full" is a multicellular A larva ( Latin; plural larvae) is a juvenile form of Animal with indirect development, undergoing Metamorphosis (for example

The time between when an egg is fertilized and when the spider begins to take the shape of an adult spider is referred to as the embryonic stage. As the spider enters the larval stage, it begins to look more and more like a full grown spider. It enters the larval stage as a prelarva and, through subsequent moults, reaches its larval form, a spider-shaped animal feeding off its yolk supply. Ecdysis is the Molting of the Cuticula in Arthropods and related groups ( Ecdysozoa) After a few more moults (also called instars) body structures become differentiated. An instar is a developmental stage of Arthropods, such as Insects, between each moult ( ecdysis) until sexual maturity is reached Soon, all organ systems are complete and the animal begins to hunt on its own; it has reached the nympho-imaginal stage. ^[4]

This stage is differentiated into two sub-stages: the nymph, or juvenile stage and the imago, or adult stage. Exuvia (alternative spelling exuvium, plural exuviae) is a term used in Biology to describe the remains of an Exoskeleton that is left after A spider does not become sexually mature until it makes the transition from nymph to imago. Sexual maturity is the age or stage when an Organism can reproduce. ^[4] Once a spider has reached the imago stage, it will remain there until its death. After sexual maturity is reached, the general rule is that they stop moulting, but the females of some non-araneomorph species will continue to moult the rest of their lives.

Lifespan

Many spiders may only live for about a year, but a number will live two years or more, overwintering in sheltered areas. The annual influx of 'outdoor' spiders into houses in the fall is due to this search for a warm place to spend the winter. It is common for female tarantulas to live up to twenty years.

Reproduction

Spiders reproduce by means of eggs, which are packed into silk bundles called egg sacs. "Nephila" redirects here In Aramaic culture the term Nephila specifically referred to the constellation and myth of Orion. Corcovado National Park (Parque Nacional Corcovado is a National Park on the Osa Peninsula in the South West of Costa Rica (9° North 83° West which In most Birds and Reptiles an egg ( Latin ovum) is the Zygote, resulting from Fertilization of the Ovum. Spiders often use elaborate mating rituals (especially the visually advanced jumping spiders) to allow conspecifics to identify each other and to allow the male to approach and inseminate the female without triggering a predatory response. If the approach signals are exchanged correctly, the male spider must (in most cases) make a timely departure after mating to escape before the female's normal predatory instincts return.

Sperm transmission from male to female occurs indirectly. The bird dropping spider ( Celaenia excavata) derives its name from mimicking bird droppings to avoid predators mainly birds A spermatozoon or spermatozoan ( pl spermatozoa) from the Ancient Greek σπέρμα (seed and ζῷον (living being and more commonly known When a male is ready to mate, he spins a web pad upon which he discharges his seminal fluid. He then dips his pedipalps (also known as palpi), the small, leg-like appendages on the front of his cephalothorax, into the seminal fluid, picking it up by capillary attraction. The cephalothorax (call prosoma in some groups is an anatomical term used in Arachnids and Malacostracan Crustaceans for the Capillary action, capillarity, capillary motion, or wicking is the ability of a substance to draw another substance into it Mature male spiders have swollen bulbs on the end of their palps for this purpose, and this is a useful way to identify the sex of a spider in the field. With his palps thus charged he goes off in search of a female. Copulation occurs when the male inserts one or both palps into the female's genital opening, known as the epigyne. The epigyne or epigynum is the female genital opening in Spiders It is of special interest to people who study spiders because the exact shape of the epigyne He transfers his seminal fluid into the female by expanding the sinuses in his palp. Sinus is Latin for "bay" "pocket" "curve" or "bosom" Once the sperm is inside her, she stores it in a chamber and only uses it during the egg-laying process, when the eggs come into contact with the male sperm for the first time and are fertilized; this may be why the vivipary has never evolved in spiders. A viviparous Animal is an animal employing vivipary: the embryo develops inside the body of the mother as opposed to outside in an egg ( Ovipary

Very unusual behaviour is seen in spiders of the genus Tidarren: the male amputates one of his palps before maturation and enters his adult life with one palp only. A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic Tidarren is a genus of spiders The males are much smaller than females The palpi constitute 20% of the body mass of males of this species, and since this weight greatly impedes its movement, by detaching one of the two he gains increased mobility. In the Yemeni species Tidarren argo, the remaining palp is then torn off by the female. Yemen ( Arabic: اليَمَن al-Yaman officially the Republic of Yemen ( Arabic: الجمهورية اليمنية al-Jumhuuriyya The separated palp remains attached to the female's epigynum for about four hours and apparently continues to function independently. In the meantime the female feeds on the palpless male. ^[5]

Sacrificial males

Main article: Spider cannibalism

It is a common belief that male spiders, which usually are significantly smaller than the females, are likely to be killed after or during mating, or sometimes even before mating can occur. Sacrificial fathers It is often said that the male (usually significantly smaller than the female down to 1% of her size as seen in Tidarren sisyphoides) is likely

Even in some species of widow spiders, which are named exactly for this belief, the male may live in the female's web for some time without being harmed. The widow spiders are members of the genus Latrodectus, in the family Theridiidae. However, in over 60% of cases the female of one species, the Australian redback spider, kills and eats the male after it inserts its second palpus into the female genital opening^[6] Males that 'sacrifice' themselves gain the benefit of increasing their paternity relative to males who do not get cannibalized since they feed the female that will lay and tend the resulting fertilized eggs. The Redback spider ( Latrodectus hasselti) is a potentially dangerous Spider native to Australia. Pedipalps, are the second pair of Appendages of the Prosoma in the subphylum Chelicerata.

In many other species, males are sometimes killed by females. In at least some of these cases it's likely that the males are simply mistaken as prey. The risk of this happening is greater if the female is hungry. To counter this, some male spiders offer a "bribe" to the female, in form of a fly or other prey, prior to the mating.

Ecology

Spiders have a great range of variation and lifestyle, although all are predatory.

While spiders are generalist predators, in actuality their different methods of prey capture often determine the type of prey taken. Thus web-building spiders rarely capture caterpillars, and crab spiders that ambush prey in flowers capture more bees, butterflies and some flies than other insects. Caterpillars are the Larval form of a member of the order Lepidoptera (the Insect order comprising butterflies and Moths Bees are flying Insects closely related to Wasps and Ants Bees are a Monophyletic lineage within the superfamily Apoidea A butterfly is an Insect of the order Lepidoptera. Like all Lepidoptera butterflies are notable for their unusual life cycle with a Groups of families that tend to take certain types of prey because of their prey capture methods are often called guilds. Guilds are groups of Species that exploit the same resources in the same way therefore sharing a similar Ecological niche. A few spiders are more specialized in their prey capture. Dysdera captures and eats sowbugs, pillbugs and beetles, while pirate spiders eat only other spiders. Dysdera is a genus of spiders from the family Dysderidae, with more than 200 species Woodlice (known by many Common names see below) are Crustaceans with a rigid segmented long Exoskeleton and fourteen jointed limbs Armadillidiidae is a family of woodlice, a terrestrial Crustacean group in the order Isopoda. Beetles are the group of Insects with the largest number of known Species. The family Mimetidae, commonly called pirate spiders, are Spiders which typically feed on other spiders Bolas spiders in the family Araneidae use sex pheromone analogs to capture only the males of certain moth species. Bolas Spiders are unusual orb-weaver spiders that do not spin the typical web. A pheromone (from Greek φέρω phero "to bear" + ‘ορμόνη " Hormone " is a Chemical that triggers a natural Despite their generally broad prey ranges, spiders are one of the most important links in the regulation of the populations of insects. Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described

Behavior

Spiders show a wide variety of behavior, from the ballet-like mating dances of certain jumping spiders to the seeming athletics of bolas spiders snatching their prey. Ballet is a formalized form of Dance with its origins in the French court further developed in France and Russia as a Concert dance Most diversity comes with the mode of predation, for example whether the spider waits for it in its orb web, or hunts it down.

Predatory techniques

Main article: Spider diversity

Although spider predatory technique is diverse, as soon as a spider makes contact with its prey, it will usually bite it.

Spiders bite their prey, and occasionally animals that cause them pain or threaten them, for two reasons: First, they inflict mechanical damage, which, in the case of a spider that is as large as or larger than its prey, can be severe. Second, they can inject venom via their hollow fangs. This article is about the class of Biotoxins For other uses see Venom (disambiguation and Venomous (disambiguation. FANG is a Japanese Manga series by Yoshihiro Takahashi. Story Characters;Asikari: (Wolf/ German Shepherd Many genera, such as the widow spiders, inject neurotoxins that can spread through the prey's entire body and interfere with vital body functions. The widow spiders are members of the genus Latrodectus, in the family Theridiidae. A neurotoxin is a Toxin that acts specifically on nerve cells ( Neurons, usually by interacting with Membrane proteins such as Ion channels Other genera inject venom that produces tissue damage at the bite location. Tissue is a cellular organizational level intermediate between cells and a complete organism In the larger victims that do not die from these attacks, painful lesions over a wide area can remain for an extended time. Pain, in the sense of physical pain, is a typical sensory experience that may be described as the unpleasant awareness of a noxious stimulus or bodily harm The spitting spiders have modified their poison glands to produce a mixture of venom and sticky substance that works as glue and immobilises the prey. Spitting spiders (family Scytodidae) are Spiders of the Genus Scytodes and their relatives

Although there are no herbivore spiders, some species in the families Anyphaenidae, Corinnidae, Clubionidae, Thomisidae and Salticidae feed on plant nectar. Herbivory is a form of Predation in which an Organism, known as a herbivore, consumes principally Autotrophs ref name=Campbell>Campbell The anyphaenid sac spiders (family Anyphaenidae) are distinguished from the sac spiders and other Spiders by having the abdominal spiracle placed one The corinnid sac spiders (family Corinnidae) like the other clubionoid families have a very confusing taxonomic history The sac spiders of the family Clubionidae have a very confusing taxonomic history Crab spiders make up the Thomisidae family of the Araneae order The jumping spider family ( Salticidae) contains more than 500 described genera and over 5000 Species, making it the largest family of Spiders with about Nectar is a Sugar -rich liquid produced by plants It is produced either by the Flowers in which it attracts pollinating animals or by extrafloral ^[7] Several spider species are also known to feed on bananas, marmalade, milk, egg yolk and sausages in captivity. For the fruit see Banana. For other meanings see Banana (disambiguation. British-style marmalade is a sweet preserve with a bitter tang made from Fruit, Sugar, water and (in some commercial brands a Gelling agent Milk is an opaque white liquid produced by the Mammary glands of female Mammals (including Monotremes. An egg yolk is the part of an egg which serves as the Food source for the developing Embryo inside A sausage is a prepared Food, usually made from Ground meat, animal fat salt and Spices (sometimes with other ingredients such as herbs typically packed ^[7]

Spider webs

Main article: Spider web

Some spiders spin funnel-shaped webs; others make sheet webs; spiders like the black widow make tangled, maze-like, webs; and still others make the spiral "orb" webs that are most commonly associated with spiders. Myrmarachne is a genus of jumping Spiders which imitate an ant by waving their front legs in the air to simulate antennae A funnel is a pipe with a wide often conical mouth and a narrow stem In Mathematics, a spiral is a Curve which emanates from a central point getting progressively farther away as it revolves around the point These webs may be made with sticky capture silk, or with "fluffy" capture silk, depending on the type of spider. Webs may be in a vertical plane (most orb webs), a horizontal plane (sheet webs), or at any angle in between. Most commonly found in the sheet-web spider families, some webs will have loose, irregular tangles of silk above them. These tangled obstacle courses serve to disorient and knock down flying insects, making them more vulnerable to being trapped on the web below. They may also help to protect the spider from aerial predators such as birds and wasps. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. A wasp is any Insect of the order Hymenoptera and suborder Apocrita that is neither a Bee nor Ant.

The spider, after spinning its web, will then wait on, or near, the web for a prey animal to become trapped. The spider can sense the impact and struggle of a prey animal by vibrations transmitted along the web lines.

Other species of spiders do not use webs for capturing prey directly, instead pouncing from concealment (e. g. trapdoor spiders) or running them down in open chase (e. Trapdoor spiders (superfamily Ctenizoidea, family Ctenizidae) are medium-sized Mygalomorph Spiders that construct g. wolf spiders). The net-casting spider balances the two methods of running and web-spinning in its feeding habits. The Spider family Deinopidae consists of stick-like elongate spiders that build unusual webs that they suspend between the front legs This spider weaves a small net that it attaches to its front legs. It then lurks in wait for potential prey and, when such prey arrives, lunges forward to wrap its victim in the net, bite and paralyze it. Hence, this spider expends less energy catching prey than a primitive hunter such as the Wolf spider. It also avoids the energy cost of weaving a large orb-web. The diving bell spider does not use its web directly in prey capture, but has modified it into an underwater diving bell. The diving bell spider or water spider, Argyroneta aquatica, is a Spider which lives entirely under water even though it could survive on land Even species whose ancestors were building spiral orb webs have given rise to spiders who no longer make webs, for instance some Hawaiian spiny-legged spiders (genus Tetragnatha, family Tetragnathidae) have abandoned web construction entirely. The long-jawed orb weavers or long jawed spiders (family Tetragnathidae) are elongated Spiders with long legs and Chelicerae.

Some spiders manage to use the 'signaling snare' technique of a web without spinning a web at all. Several types of water-dwelling spiders will rest their feet on the water's surface in much the same manner as an orb-web user. When an insect falls onto the water and is ensnared by surface tension, the spider can detect the vibrations and run out to capture the prey.

Hunting spiders

Many spiders do not build webs for catching prey. Some examples include:

• Brazilian wandering spider
• Brown recluse spider
• Huntsman spiders
• Jumping spiders
• Lynx spiders
• Nursery web spiders
• Spitting spiders
• Tarantulas
• Wolf spiders (Lycosidae)
• Yellow sac spider
• Assassin spider

Ambush predators

Some actively lure prey (the Bolas spiders) and may capture them with a sticky ball of silk on a line; others (like the crab spiders, trapdoor spiders, or the six-eyed sand spider) wait in a high-traffic area and directly attack their prey from ambush. The Brazilian wandering spiders ( Phoneutria spp) armed spiders ("aranhas armadeiras" as they are known in Portuguese) or The brown recluse Spider, Loxosceles reclusa, is a well-known member of the family Sicariidae (formerly placed in a family "Loxoscelidae" Huntsman spider is a common name given to the family Sparassidae (formerly Heteropodidae) The jumping spider family ( Salticidae) contains more than 500 described genera and over 5000 Species, making it the largest family of Spiders with about Lynx Spiders are hunting spiders that spend their lives on plants flowers and shrubs Nursery web spiders are Spiders of the family Pisauridae They resemble Wolf spiders (family Lycosidae but they carry their egg sacs by means of their Spitting spiders (family Scytodidae) are Spiders of the Genus Scytodes and their relatives Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species Cheiracanthium is a genus of spiders in the Miturgidae family The Archaeidae are a Spider family with 25 described species in three genera Bolas Spiders are unusual orb-weaver spiders that do not spin the typical web. Crab spiders make up the Thomisidae family of the Araneae order Trapdoor spiders (superfamily Ctenizoidea, family Ctenizidae) are medium-sized Mygalomorph Spiders that construct The six-eyed sand spider ( Sicarius hahni) is a medium-sized Spider found in deserts and other sandy places in southern Africa.

Defense

Many spiders will attempt to protect themselves by biting, especially if they are unable to flee. The Chilean rose tarantula ( Grammostola rosea) also know as the Chilean flame tarantula, Chilean Fire Tarantula or the Chilean Red Haired Tarantula Some tarantulas have a second kind of defense, a patch of urticating hairs, or urticating setae, on their abdomens, which is generally absent on modern spiders and Mesothelae. Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species Urticating hairs are one of the primary Defense mechanisms used by some New World Tarantulas and lepidopteran caterpillars The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant These ultra-fine hairs causes irritation and sometimes even allergic reactions in the attacker. Certain other species have specialized defense tactics. For example, the golden wheeling spider (Carparachne aureoflava) of the desert of Namibia escapes tarantula hawks (a species of wasp that lays its eggs in a paralyzed spider so the larvae have enough food when they hatch) by flipping onto its side and cartwheeling away. The tarantula hawk is the common name for species in the genera Pepsis and Hemipepsis of the family Pompilidae, in the insect A wasp is any Insect of the order Hymenoptera and suborder Apocrita that is neither a Bee nor Ant.

Social spiders

A few species of spiders that build webs live together in large colonies and show social behavior, albeit not as well evolved as in social insects. Eusociality ( Greek eu: "good" + "social" is a term used for the highest level of social organization in a hierarchical classification The most social species is probably Anelosimus eximius (Theridiidae), which can form colonies of up to fifty thousand individuals. Anelosimus is a Genus of tangle-foot spiders ( Theridiidae) described by Eugène Simon, in 1891 from Venezuela to include the South American Social The tangle-web spiders, also known as cobweb spiders and comb-footed spiders (family Theridiidae) are a large group (over 2200 Species in Other communal spiders include several Philoponella species (Uloboridae), Agelena consociata (Agelenidae) and Mallos gregalis (Dictynidae). Philoponella is a genus of uloborid spiders Like all Uloboridae these species have no Venom. The hackled orbweavers (family Uloboridae) have the special distinction of being non- venomous Spiders Their lack of poison glands is a secondary evolved Spiders of the genus Agelena weave web funnels that trap their prey The Araneomorph funnel-web spiders of the family Agelenidae include the common grass spiders of the genus Agelenopsis, as well as the purportedly venomous Dictynidae is a family of Cribellate (hackled band-producing Spiders Most spiders in this family build irregular webs close to or directly on the ^[8]

Web types

Tangleweb spiders

Members of this group (family Theridiidae) are characterized by irregular, messy-looking, tangled, three-dimensional (non-sticky) webs, also popularly known as cobwebs, generally low and anchored to the ground or floor and wall. The tangle-web spiders, also known as cobweb spiders and comb-footed spiders (family Theridiidae) are a large group (over 2200 Species in They are commonly found in or near buildings; some build webs in bushes. The spider generally hangs in the center of its web, upside-down. Prey is generally ground-dwelling insects such as ants or crickets, in addition to small flying insects. These include the infamous black widows, the minute happyface spider, and thousands of other species. The black widow spider is a group of Spiders which includes the southern black widow ( Latrodectus mactans) the northern black widow Theridion grallator, also known as the "happyface" Spider, is a member of the Theridiidae family

Orb web spiders

Spiders in several families (eg. Nephila clavata, also known as Jorō spider (in Japanese: ja ジョロウグモ / Jorō-gumo) is a member of Golden orb-web spider. , Araneidae, Tetragnathidae, Nephilidae) spin the familiar spiral snare that most people think of as the typical spider web. The orb-weaver spiders (family Araneidae) are the builders of spiral wheel-shaped webs often found in gardens fields and forests The long-jawed orb weavers or long jawed spiders (family Tetragnathidae) are elongated Spiders with long legs and Chelicerae. The Nephilidae are a Spider family with 75 described species in four genera On average, an orb-weaving spider takes 30 minutes to an hour to weave a web. They range in size from quite large (6+ cm) to very small (<1 cm), but all are quite harmless to humans, beyond the shock entailed from walking into a face-height web and having a large spider dangling from your nose. A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth Many of the daytime hunters have a 'ferocious' appearance, with spines or large 'fangs', but they are almost invariably inoffensive, preferring to drop on a dragline to the ground when disturbed, rather than bite, which can nevertheless be quite painful.

Other types of webs

Some (the Linyphiidae) make various forms of bowl- or dome-shaped webs with or without a flat sheet or a tangled web above or below. Linyphiidae is a family of Spiders including more than 4300 described Species in 578 genera worldwide Some make a flat platform extending from a funnel-shaped retreat, with generally a tangle of silk above the web. The common northern hemisphere 'funnel-web', 'house' or 'grass' spiders are only superficially similar to the notorious Sydney funnel-web spider, and are generally considered to be quite harmless. Australian funnel-web spiders are very venomous Spiders of the family Hexathelidae. Some of the more primitive group Atypidae may make tubular webs up the base of trees, from inside which they bite insects that land on the webbing. The atypical tarantulas or purseweb spiders (family Atypidae) consist of only three genera. These spiders look quite ferocious, but are not generally considered to be particularly dangerous to humans.

Evolution

Main article: Spider evolution

Trigonotarbids, spider-like arachnids, were among the oldest known land arthropods. The evolution of spiders has been going on for at least 400 million years, since the first true Spiders (thin-waisted Amber is Fossil tree Resin, which is appreciated for its color and beauty The Order Trigonotarbida is an extinct group of Arachnids whose Fossil record extends from the Silurian to the Lower Permian and are Like spiders, they were terrestrial, respired through book lungs, and walked on eight legs with two additional legs adapted to use around their mouth. However, they were not true spiders, not even ancestral to them, but represented independent offshoots of the Arachnida.

True spiders (thin-waisted arachnids) evolved about 400 million years ago, and were among the first species to live on land. They are distinguished by abdominal segmentation and silk producing spinnerets. A spinneret is a spider's silk -spinning organ. It is usually on the underside of a spider's Abdomen, to the rear The Pedipalpi (including whip scorpions) are believed to constitute the sister group to the Araneae. Pedipalps, are the second pair of Appendages of the Prosoma in the subphylum Chelicerata. A uropygid, commonly known as a whip scorpion, is an invertebrate animal belonging to the former order "Uropygi" in the class Arachnida, ^[9]

Most of the early segmented fossil spiders belonged to the Mesothelae, a group of primitive spiders with the spinnerets placed underneath the middle of the abdomen, rather than at the end as in modern spiders (Opisthothelae). The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant They were probably ground dwelling predators of other primitive arthropods. Silk may have been used simply as a protective covering for the eggs, a lining for a retreat hole, and later perhaps for simple ground sheet web and trapdoor construction.

As plant and insect life diversified so also did the spider's use of silk. Spiders with spinnerets at the end of the abdomen (Mygalomorphae and Araneomorphae) appeared more than 250 million years ago, presumably promoting the development of more elaborate sheet and maze webs for prey capture both on ground and foliage, as well as the development of the safety dragline. The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action

By the Jurassic, the sophisticated aerial webs of the orb weaving spiders had already developed to take advantage of the rapidly diversifying groups of insects. The Jurassic is a geologic period and system that extends from about Ma (million years ago to  Ma that is from the end of the Triassic to the beginning A spider web preserved in amber, thought to be 110 million years old, shows evidence of a perfect orb web. It is believed that adhesive capture threads, as opposed to cribellate threads, evolved about 135 million years ago. A cribellum is a kind of comb-like device in certain Spiders used to separate fibers of Silk drawn from its Spinnerets into many extremely fine fibers giving ^[10]

The ability to weave orb webs is thought to have been "lost", and sometimes even re-evolved or evolved separately, in different breeds of spiders since its first appearance.

Taxonomy

Main article: Spider taxonomy

Araneae    Mesothelae    Opisthothelae        Mygalomorphae Araneomorphae

Almost 40,000 species of spiders (order Araneae) have been identified and are currently grouped into 111 families by arachnologists, but because of difficulties in collecting these often very minute and evasive animals, and because of many specimens stored in collections waiting to be described and classified, it is believed that up to 200,000 species may exist. Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. In Biological classification, family ( Latin Arachnology (from Greek grc ἀράχνη arachnē, "spider" and grc -λογία -logia) is the scientific study of Specimen are a British band formed in the 1980s Their music has been described as being comprised of many different genres of music including Glam, Goth A Museum is distinguished by a collection of often unique objects that forms the core of its activities for exhibitions Education, Research

The order is composed of three suborders. In the non-venomous primitive Mesothelae, body segmentation is clearly visible, demonstrating the link of spiders with their segmented arthropod ancestors. The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant

The two other suborders, the Mygalomorphae (trapdoor spiders, funnel-web spiders, tarantulas) and the Araneomorphae ("modern" spiders), are sometimes grouped together as Opisthothelae. The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action The latter account for about 94% of all spider species.

Mesothelae

Main article: Mesothelae

The Mesothelae include the only recent family Liphistiidae. The Mesothelae are a suborder of Spiders (Order Araneae that includes the extinct families Arthrolycosidae and Arthromygalidae and the only Extant The spider family Liphistiidae comprises 5 genera and 85 Species from Southeast Asia, China, and Japan. Two more families (Arthrolycosidae and Arthromygalidae) are recognized from fossil evidence only. Arthrolycosidae is an extinct family of primitive Spiders that supposedly bear some resemblance to the Wolf spiders The Arthromygalidae are primitive fossil spiders that supposedly bear some resemblance to the Tarantulas

The Liphistiidae are burrowing spiders only found in Southeast Asia, China, and Japan with about 90 species in 5 genera. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National For a topic outline on this subject see List of basic Japan topics. Spiders of this remnant suborder are very rare, and are among the most "primitive" types of spiders in existence. Primitive is a descriptive term often used in the field of Evolution to describe particular Species or traits that are characteristic of an older evolutionary

Recent Mesothelae are characterized by the narrow sternum on the ventral side of the prosoma. The sternum (from Greek στέρνον sternon, "chest" or breastbone) is a long flat Bone located in the center of the thorax (chest The cephalothorax (call prosoma in some groups is an anatomical term used in Arachnids and Malacostracan Crustaceans for the Several plesiomorphic characters may be useful in recognizing these spiders: there are tergite plates on the dorsal side and the almost-median position of the spinnerets on the ventral side of the opisthosoma. Cladistics is the hierarchical classification of Species based on evolutionary ancestry A tergum (plural terga, associated adjective tergal) is the dorsal portion of an Arthropod segment other than the head In Anatomy, the dorsum is the upper side of animals that typically run fly or swim in a horizontal position and the back side of animals (like humans that walk upright In Probability theory and Statistics, a median is described as the number separating the higher half of a sample a population or a Probability distribution A spinneret is a spider's silk -spinning organ. It is usually on the underside of a spider's Abdomen, to the rear In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species The opisthosoma is the posterior portion of the Arachnids body behind the Prosoma (cephalothorax

Mygalomorphae

Main article: Mygalomorphae

The Mygalomorphae are also called the Orthognatha, referring to the orientation of the fangs roughly in line with the body axis. Mexican Red-Kneed Tarantula The Mexican Red-kneed Tarantula ( Brachypelma smithi) is a Species of burrowing Tarantula native to the western face of the The Mygalomorphae, (also called the Orthognatha) are an Infraorder of Spiders The latter name comes from the orientation of the fangs which The Cheliceral fang of a Spider is so called because the Chelicerae of spiders consist of two parts, one containing all or part of the glands that produce This suborder includes the heavy bodied, stout legged spiders popularly known as tarantulas as well as the dangerous Australasian funnel-web spiders. Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species Australian funnel-web spiders are very venomous Spiders of the family Hexathelidae. They have ample poison glands that lie entirely within their chelicerae. In the context of Biology, poisons are substances that can cause damage, Illness, or Death to Organisms usually by The Chelicerae are mouth parts of the Chelicerata, an Arthropod Subphylum that includes Arachnids, Merostomata Their chelicerae and fangs are large and powerful. Occasionally members of this suborder will even kill small fish, small mammals, etc. Fish are aquatic Vertebrate animals that are typically ectothermic (previously Cold-blooded) covered with scales, and equipped with two Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Most members of this suborder occur in the tropics and subtropics, but their range can extend farther toward the poles, e. The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23 The subtropics are the zones of the Earth immediately north and south of the tropic zone which is bounded by the Tropic of Cancer and the Tropic of g. into the southern and western regions of the United States and Canada, the northern parts of Europe and south into Argentina and Chile. The United States of America —commonly referred to as the Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page For a topic outline on this subject see List of basic Argentina topics. Chile, officially the Republic of Chile ( Spanish:) is a country in South America occupying a long and narrow Coastal strip wedged between the

Araneomorphae

Main article: Araneomorphae

The Araneomorphae, (previously called the Labidognatha), are often known as the modern spiders. The European garden spider ( Araneus diadematus) or diadem spider, also called the cross spider in Eastern Europe, is a very common and well-known The Araneomorphae are a Suborder of Spiders They are distinguished by having Chelicerae (fangs that point diagonally forward and cross in a pinching action

Araneomorphae are distinguished by fangs that move at a 90 degree angle to the body axis, like a pair of pincers. Most of the spiders that people encounter in daily life belong to this suborder, which makes up 94% of all spider species.

There are approximately 95 families in this suborder, ranging from the minute Patu digua (0. Spider taxonomy is the Alpha taxonomy of the Spiders members of the Araneae order of the arthropod Patu digua is by some accounts considered to be the smallest Spider in the world with males reaching a body size of about 0 37 mm) to the big and flashy Argiope, from the common orb-weaver spiders to the abstruse assassin spiders, from the reclusive tree trapdoor spiders to the inquisitive jumping spiders. The Millimetre ( American spelling: millimeter, symbol mm) is a unit of Length in the Metric system, equal to The Genus Argiope includes rather large and spectacular Spiders that have often a strikingly coloured Abdomen. The orb-weaver spiders (family Araneidae) are the builders of spiral wheel-shaped webs often found in gardens fields and forests The Archaeidae are a Spider family with 25 described species in three genera The tree trapdoor spiders ( Migidae) are a Spider family with about 90 species in 10 genera The jumping spider family ( Salticidae) contains more than 500 described genera and over 5000 Species, making it the largest family of Spiders with about

Creatures often mistaken for spiders

In addition to the true spiders, there are several arachnids commonly mistaken for spiders, but that are not true spiders. Arachnids are a class ( Arachnida) of joint-legged Invertebrate Animals in the subphylum Chelicerata.

• Camel spider, a species of solifugid (also commonly called sun-spiders or wind-scorpions), are the source of many urban legends. Solifugae is an order of Arachnida containing more than 1000 described Species in about 140 genera. Solifugae is an order of Arachnida containing more than 1000 described Species in about 140 genera. An urban legend or urban myth is a form of modern Folklore consisting of stories thought to be factual by those circulating them Although they have no venom the camel spider has been known to attack humans, focusing on exposed skin, and with fangs capable of tearing human flesh. Several myths surround camel spiders, and their size is usually exaggerated. While they are really the size of an adult human hand, myths tell they are as large as the lower half of an adult human leg. Also, they are harmless to humans, and will only attack if disturbed.
• The daddy long-legs or harvestman is a member of the order Opiliones. Harvestmen are eight-legged Invertebrate animals belonging to the order Opiliones (formerly Phalangida) in the class Arachnida in the subphylum These round-bodied arachnids have only two eyes and their heads are fused to their bodies. However, the name "daddy long-legs" is sometimes used to refer to cellar spiders, which have a similar leg shape; these are true spiders. The Pholcidae are a Spider family in the suborder Araneomorphae. Both are also often said to produce a deadly venom. While the harvestmen do not produce venom at all, the cellar spider's venom is completely harmless to humans. The term daddy long-legs is also used in British English to refer to the Crane fly, which is an insect and not an arachnid at all. British English or UK English ( BrE, BE, en-GB) is the broad term used to distinguish the forms of the English language used in the Insects in the family Tipulidae are commonly known as crane flies.

Spiders and people

Spider bites

Main article: Spider bite

Most spiders are unlikely to bite humans because they do not identify humans as prey. Australian funnel-web spiders are very venomous Spiders of the family Hexathelidae. '''Spiders''' occasionally bite humans Although 98-99% of spider bites are harmless more rarely the symptoms of their bites can include necrotic wounds systemic However, some spiders, even small ones, may bite humans when pinched. For instance, a common species of jumping spider (Family: Salticidae), around 3/8 inch (1 cm) long, when pinched between the folds of a human's palm may inflict a bite that is about as painful as a bee sting. The number of fatalities varies according to author, with some placing the yearly death toll as low as one person per year, worldwide.

Spiders in the world that have been linked to fatalities in humans, or have been shown to have potentially fatal bites by toxicology studies of their venom, include:

• The Brazilian wandering spider
• The Australasian funnel-web spider
• The widow spiders, including the Australian redback spider
• The six-eyed sand spider, and possibly other spiders of genus Sicarius
• The recluse spiders

Spiders that are never deadly to humans, but that are nonetheless medically significant include:

• The yellow sac spider
• Certain species of tarantulas
• The false black widows

Spiders that can inflict painful bites (often similar to a bee sting), but whose bites generally do not cause any systemic or long-lasting effects, include:

• The huntsman spider
• The redback jumping spider (not to be confused with the very dangerous redback spider, which is one of the widow spiders). The Brazilian wandering spiders ( Phoneutria spp) armed spiders ("aranhas armadeiras" as they are known in Portuguese) or The Brazilian wandering spiders ( Phoneutria spp) armed spiders ("aranhas armadeiras" as they are known in Portuguese) or Australian funnel-web spiders are very venomous Spiders of the family Hexathelidae. The widow spiders are members of the genus Latrodectus, in the family Theridiidae. The Redback spider ( Latrodectus hasselti) is a potentially dangerous Spider native to Australia. The six-eyed sand spider ( Sicarius hahni) is a medium-sized Spider found in deserts and other sandy places in southern Africa. The recluse spiders (genus Loxosceles) also known as fiddle-back or violin spiders, are a venomous genus of spiders known for Cheiracanthium is a genus of spiders in the Miturgidae family Tarantula is the common name for a group of hairy and often very large Spiders belonging to the family Theraphosidae, of which approximately 900 species The Spider genus Steatoda, in the family Theridiidae, includes over 120 recognized Species, distributed around the world (including many A bee sting strictly means a sting from a Bee ( Honey bee, Bumblebee, Sweat bee etc Huntsman spider is a common name given to the family Sparassidae (formerly Heteropodidae) The redbacked jumping spider ( Phidippus johnsoni) is one of the largest and most commonly encountered Jumping spider of western North America. The Redback spider ( Latrodectus hasselti) is a potentially dangerous Spider native to Australia.

None of these spiders will intentionally seek out humans, but they should be removed from one's house to avoid accidental injury. Many authorities warn against spraying poisons indiscriminately to kill all spiders, because doing so may actually remove one of the biological controls against incursions of the more dangerous species by ridding them of their competition.

If dangerous spiders are present in your area, be mindful when moving cardboard boxes and other such objects that may have become the shelter of a venomous spider. There is no need to be fearful; just do not grab a spider.

Spiders as food

Spiders, especially larger sorts, are eaten routinely or as a delicacy in various parts of the world, including Cambodia, where fried spider is considered a delicacy, Thailand, the Solomon Islands, and parts of South America, where living wrapped tarantulas are also sometimes taken on trips by certain indigenous tribes. The Kingdom of Cambodia ( formerly known as Kampuchea (, transliterated: Preăh Réachéanachâkr Kâmpŭchea) is a country in South East A fried spider is a regional Delicacy in Cambodia. In the Cambodian town of Skuon, locals eat fried Spiders as an everyday snack The Kingdom of Thailand (ˈtaɪlænd ราชอาณาจักรไทย, râːtɕʰa-ʔaːnaːtɕɑ̀k-tʰɑj The Solomon Islands is a country in Melanesia, east of Papua New Guinea, consisting of nearly one thousand islands South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a

Arachnophobia

Main article: Arachnophobia

Arachnophobia is a specific phobia, an abnormal fear of spiders. Saitis barbipes is a common jumping spider in the Mediterranean region where it can be found on houses and rocks Arachnophobia (from Greek Arachne (αράχνη "spider" and Phobia (φοβία "fear") is a Specific phobia, an abnormal A specific phobia is a generic term for any kind of Anxiety disorder that amounts to an unreasonable or irrational fear related to exposure to specific objects or situations Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings It is among the most common of phobias in certain regions of the world. The reactions of arachnophobics often seem irrational to others (and sometimes to the sufferers themselves). People with arachnophobia tend to feel uneasy in any area they believe could harbor spiders or that has visible signs of their presence, such as webs. If they see a spider they may not enter the general vicinity until they overcome the panic attack that is often associated with their phobia. They may feel humiliated if such episodes happen in the presence of peers or family members. The fear of spiders can be treated by any of general techniques suggested for specific phobias.

Arachnophobia is also the title of a 1990 film, as well as a spin-off video game, in which (fictitious) deadly spiders overrun a small California town. Arachnophobia is a 1990 American horror - Comedy film directed by Frank Marshall and starring Jeff Daniels and Arachnophobia is a Video game based on the film Arachnophobia. California ( is a US state on the West Coast of the United States, along the Pacific Ocean.

Spiders in symbolism and culture

Main article: Cultural depictions of spiders

There are many references to the spider in popular culture, folklore and symbolism. Throughout history there have been many cultural depictions of Spiders in popular culture mythology and symbolism The spider symbolizes patience for its hunting with web traps, and mischief and malice for its poison and the slow death this causes. It symbolizes possessiveness and storage for its spinning of its prey into a ball and taking it to its burrow (for burrowing species).

Though not all spiders spin gossamer webs, spiders have been attributed by numerous cultures with the origination of basket-weaving, knotwork, weaving, spinning and net making. Spider silk, also known as Gossamer, is a Protein Fiber spun by Spiders Spiders use their silk to make webs or other structures which function Basket weaving (also basketry, basket making, or basketmaking) is the process of Weaving unspun Vegetable Fibers into KNOT (1450 AM) is a commercial Classic Country music Radio station in Prescott Arizona, broadcasting to the Flagstaff - Prescott This article describes textile weaving For other senses of this word see Weaving (disambiguation. Spinning is an ancient textile art in which plant, animal or synthetic Fibers are twisted together to form Yarn (or thread Spiders are pervasive throughout folklore and mythology. The theme of Weaving in mythology is ancient and its lost mythic lore probably accompanied the early spread of this art Spinning and binding is evident in the etymologies of the terms religion, yoga, tantra and wyrd. A religion is a set of Tenets and practices often centered upon specific Supernatural and moral claims about Reality, the Cosmos Yoga ( Sanskrit: योग, IAST: yóga, joːgə refers to traditional physical and mental disciplines originating in India, to the Tantra ( Sanskrit: तन्त्र; " Weave " denoting continuity) tantricism or tantrism is any of several esoteric Wyrd is a concept in Old English and Old Norse culture roughly corresponding to fate or Karma.

The Moche people of ancient Peru worshipped nature. The Moche civilization (alternately the Mochica culture Early Chimu Pre-Chimu Proto-Chimu etc Peru (Perú Piruw Piruw officially the Republic of Peru ( reˈpuβlika del peˈɾu is a country in western South America. ^[11] They placed emphasis on animals and often depicted spiders in their art. ^[12]

See also

• Spider diversity
• Identifying spiders
• Spider webs in space
• Endangered spiders
• Spider-Man

Footnotes

References

• Bilger, Burkhard. "Spider Woman". The New Yorker, 5 March 2007, pp. Events 363 - Roman Emperor Julian moves from Antioch with an army of 90000 to attack the Sassanid Empire, in a Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. 66–73.
• W. S. Bristowe (1976). William Syer Bristowe (1901-1979 who wrote under the name W S The World of Spiders. Taplinger Pub Co. ISBN 0-8008-8598-8.  
• Crompton, John. The Life of the Spider, Mentor, 1950.
• Hillyard, Paul. The Book of the Spider, Random House, New York, 1994.
• Kaston, B. J. How to Know the Spiders, Dubuque, 1953.
• Main, Barbara York. Spiders, Collins (The Australian Naturalist Library), Sydney, 1976.
• Matsumoto, Toshiya (1998): Cooperative prey capture in the communal web spider, Philoponella raffray (Araneae, Uloboridae). Journal of Arachnology 26: 392–396. PDF
• Ubick, Darrell; Pierre Paquin, Paula E. Cushing, and Vincent Roth. Spiders of North America: an Identification Manual, American Arachnological Society, 2005.
• Wise, David H. "Spiders in Ecological Webs. " Cambridge University Press. Great Britain: 1993.

External links

General

• The Arachnology Home Page: Araneae — Spiders
• Spider info by Ed Nieuwenhuys
• Deutsche Arachnologische Gesellschaft e. V. — German Arachnologic Society (EN/DE)
• Wikia has a wiki on this subject: spiders
• Spider Pest Control Information — National Pesticide Information Center
• Spider webs in space
• Indoor Spiders of New England Harvard University

Regional

• Portuguese spiders
• Australian spiders
• List of spiders found in Great Britain
• University of Southern Queensland's Find-a-spider guide
• Watson, L., and Dallwitz, M.J. 2004 onwards. The families of spiders represented in the British Isles.
• Czech spiders with photos
• Spiders of the Caucasus (caucasus-spiders.info)
• Spiders of Wisconsin

Morphology

• Histology of Salticid Spiders

Taxonomy

• Platnick, Norman I. Wikia (originally Wikicities) is a selective Free web hosting service for Wikis (or Wiki farm) operated by Wikia Inc Spider webs in space were spun in 1973 aboard Skylab, involving two female European garden spiders (cross spiders called Arabella and Anita (2008): The world spider catalog, version 8. 5. American Museum of Natural History.
• Canadian Arachnologist & Nearctic Spider Database
• Total number of described spider genera and species

Pictures

• Tarantulas.us - Gallery — The largest photo gallery of all tarantula's species.
• Spiders of North America Library of reference quality large format photographs with taxonomy and descriptions.
• Photos of spiders from around the world.
• Free Nature Photos, spiders
• Macro Photography - Pictures of spiders, image gallery (commercial, but very good pictures)

Other

• Webs made by spiders fed on drug-dosed flies
• Spiders Research on Spiders from Science Daily.
• University of California evaluations of spider bite severity
• http://www.tarantulatour.com

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