NationMaster - Encyclopedia: Arachnid

Arachnids are a class (Arachnida) of joint-legged invertebrate animals in the subphylum Chelicerata. The term arachnid is from the Greek word άράχνη or arachne, meaning spider,^[1] and also referring to the mythological figure Arachne. Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... Invertebrate is an English word that describes any animal without a spinal column. ... For other uses, see Animal (disambiguation). ... Classes Arachnida- spiders, scorpions, etc. ... The bust of Zeus found at Otricoli (Sala Rotonda, Museo Pio-Clementino, Vatican) Greek mythology is the body of stories belonging to the Ancient Greeks concerning their gods and heroes, the nature of the world and the origins and significance of their own cult and ritual practices. ... For other uses, see Arachne (disambiguation). ...

Arachnids are chiefly terrestrial arthropods, but are also found in freshwater and, with the exception of the pelagic zone, in all marine environments. They comprise some 65,000 to 73,000 named species, including spiders, scorpions, harvestmen, ticks, and mites. Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... For other uses, see Species (disambiguation). ... For other uses, see Spider (disambiguation). ... Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ... Diversity 4 suborders Suborders Cyphophthalmi Eupnoi Dyspnoi Laniatores Harvestmen (also known as daddy long-legs) are eight-legged invertebrate animals belonging to the order Opiliones (formerly Phalangida) in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families Ixodidae - Hard ticks Argasidae - Soft ticks Nuttalliellidae - ????? ticks Wikispecies has information related to: Ixodoidea Tick is the common name for the small arachnids that, along with other mites, constitute the order Acarina. ... Mites, along with ticks, belong to the subclass Acarina (also known as Acari) and the class Arachnida. ...

It is commonly understood that arachnids have four pairs of legs, and that arachnids may be easily distinguished from insects by this fact (insects have six legs or three pairs). Interestingly, arachnids generally have a total of 6 pairs of appendages--two pairs of which have become adapted for feeding, defense, and sensory perception. The first pair of appendages, the chelicerae, serve in feeding and defense. The next pair of appendages, the pedipalps have been adapted for feeding, locomotion, and/or reproductive functions. In Solifugae, the palpi are quite leg-like and make Solifugae appear to have ten legs. The larvae of mites (and Ricinulei) have only six legs; the fourth pair appears when they moult into nymphs. However, there are also adult mites with six, or even four legs.^[2] Orders Subclass Apterygota Archaeognatha (bristletails) Thysanura (silverfish) Subclass Pterygota Infraclass Paleoptera (Probably paraphyletic) Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Superorder Exopterygota Grylloblattodea (ice-crawlers) Mantophasmatodea (gladiators) Plecoptera (stoneflies) Embioptera (webspinners) Zoraptera (angel insects) Dermaptera (earwigs) Orthoptera (grasshoppers, etc) Phasmatodea (stick insects) Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Psocoptera... Types of chelicerae: jackknife (in green), scissor (in blue) and 3-segmented chelate (in red) The Chelicerae are mouth parts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata (horseshoe crabs), and Pycnogonida (sea spiders). ... Male European garden spider with swollen pedipalps Pedipalps are a pair of feelers on a spiders face. ... For other uses, see Reproduction (disambiguation) Reproduction is the biological process by which new individual organisms are produced. ... Families see text The order Solifugae is a group of arachnids, containing more than 1,000 described species in about 140 genera. ... A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ... A ricinuleid, commonly known as a hooded tickspider, is an invertebrate animal belonging to the order Ricinulei in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Ecdysis is the molting of the cuticula in arthropods and related groups (Ecdysozoa). ... Praying mantis nymphs, approximately 4mm long, clustered on a leaf In biology, a nymph is the immature form of some insect species, which undergoes incomplete metamorphosis (Hemimetabolism) before reaching its adult stage; unlike a larva, a nymphs overall form already resembles that of an adult. ...

Arachnids are further distinguished by the fact they have no antennae and no wings. Their body is organized into two tagma called the prosoma, or cephalothorax, and the opisthosoma, or abdomen. The cephalothorax (Prosoma) is derived from the fusion of the cephalon (head) and the thorax. The abdomen (opisthosoma) can be further divided into the preabdomen and postabdomen in many taxa, although in some orders such as the Acari the abdomenal sections are fused.^[3] Insects display a wide variety of antennal shapes. ... Wing structure of a dragonfly (family Gomphidae) Insect wings are outgrowths of the insect exoskeleton that enable insects to fly. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... The opisthosoma is the posterior portion of the arachnids body behind the prosoma. ... The abdomen in a human and an ant. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... Cephalon, Inc. ... Diagram of a tsetse fly, showing the head, thorax and abdomen The thorax is a division of an animals body that lies between the head and the abdomen. ... The abdomen in a human and an ant. ... Families Tetranychidae - Spider mites Eriophyidae - Gall mites Sarcoptidae - Sarcoptic Mange mites The mites and ticks, order Acarina or Acari, belong to the Arachnida and are among the most diverse and successful of all the invertebrate groups, although some way behind the insects. ...

There are some important modifications that are particularly important for the terrestrial lifestyle of an arachnid, such as internal respiratory surfaces in the form of trachea, or modification of the book gill into a book lung, an internal series of vascular lamellae used for gas exchange with the air. Further adaptations are appendages modified for more efficient locomotion on land, internal fertilisation, special sensory organs, and water conservation enhanced by more efficient excretory structures (coxal glands and Malpighian tubules) as well as a waxy layer covering the cuticle. Many terrestrial arthropods have evolved a closed respiratory system composed of spiracles, tracheae, and tracheoles to transport metabolic gasses to and from tissue. ... A book lung is a type of respiration organ used for atmospheric gas exhange and is found in arachnids, such as scorpions and spiders. ... A book lung is a type of respiration organ used for atmospheric gas exchange and is found in arachnids, such as scorpions and spiders. ... Vascular is an adjective for the word vessel and refers to tube-like structures. ... Lamellae is a term for several very different biological and material structures. ... Gas exchange or respiration takes place at a respiratory surfaceâ€”a boundary between the external environment and the interior of the body. ... A limb (from the Old English lim) is a jointed appendage of the human or animal branch of a tree; a representative, branch or member of a group or organization. ... In a general sense, locomotion simply means active movement or travel, applying not just to biological individuals. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Excretion is the biological process by which an organism separates waste products from its body. ... Stylised diagram of insect digestive tract showing malpighian tubule (Orthopteran type) The Malpighian tubule system is a type of excretory and osmoregulatory system found in some Uniramia (insects and Myriapoda) and arachnids. ...

Arachnids are mostly carnivorous, feeding on the pre-digested bodies of insects and other small animals. Only in the harvestmen and among mites, such as the house dust mite, is there ingestion of solid food particles and thus exposure to internal parasites ^[4], althougth it is not unusual for spiders to eat their own silk. Several groups are largely venomous - they secrete venom from specialized glands to kill prey or enemies. Several mites are parasites, some of which are carriers of disease. Arachnids usually lay eggs, which hatch into immatures that resemble adults. Carnivorism redirects here. ... The Phalangids or Opiliones (better known as harvestmen or daddy longlegs) are eight-legged invertebrate animals belonging to the order Opiliones in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families Tetranychidae - Spider mites Eriophyidae - Gall mites Sarcoptidae - Sarcoptic Mange mites The mites and ticks, order Acarina or Acari, belong to the Arachnida and are among the most diverse and successful of all the invertebrate groups, although some way behind the insects. ... Binomial name Trouessart, 1897 The house dust mite (sometimes abbreviated by allergists to HDM), is a cosmopolitan guest in human habitation. ... It has been suggested that Snake poison be merged into this article or section. ... Human submaxillary gland. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... This article is about the medical term. ... In most birds and reptiles, an egg (Latin ovum) is the zygote, resulting from fertilization of the ovum. ...

As all arthopods, they have an external skeleton, and they also have an internal structure of cartilage like tissue called the endosternite, where certain muscle groups are attached. Calcification in the endosternite has been found in some Opiliones [1]. Cartilage is a type of dense connective tissue. ...

Arachnids have two kinds of eyes, the lateral and median ocelli. The lateral ocelli evolved from compound eyes and may have a tapetum, which enhances the efficiency of photon capture. The median ocelli develop from a transverse fold of the ectoderm. The ancestors of modern arachnids probably had both types, but modern ones often lack one type or the other.^[4] Ocelli is one of the types of photoreceptor organs in animals. ... Compound eye of a dragonfly A compound eye is a visual organ found in arthropods such as insects and crustaceans. ... Tapetum lucidum in a calf eye, with the retina hanging down. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... The ectoderm is outermost of the three germ layers of the developing embryo, the other two being the mesoderm and the endoderm. ...

Systematics

It is estimated that a total of 98,000 arachnid species have been described, and that there may be up to 600,000 in total, including undescribed species ^[5]. For other uses, see Spider (disambiguation). ... The Liphistiidae are the most primitive living spiders, placed in their own suborder, called the Mesothelae. ... In phylogenetics, basal members of a group diverged earlier than a subgroup of others (or vice versa). ... A spinneret is a spiders silk spinning organ. ... Diversity 111 families, 40,000 species Suborders Mesothelae Mygalomorphae Araneomorphae See table of families Wikispecies has information related to: Spiders A South American Argiope Spiders are predatory invertebrate animals with two body segments, eight legs, no chewing mouth parts and no wings. ... The Araneomorphae, previously called the Labidognatha, are a suborder of spiders. ... Families Suborder Mesothelae Liphistiidae (primitive burrowing spiders) Suborder Mygalomorphae Atypidae (atypical tarantula) Antrodiaetidae (folding trapdoor spider) Mecicobothriidae (dwarf tarantulas) Hexathelidae (venomous funnel-web tarantula) Dipluridae (funnel-web tarantula) Cyrtaucheniidae (wafer trapdoor spider) Ctenizidae (trapdoor spider) Theraphosidae (tarantula) Suborder Araneomorphae Hypochilidae (lampshade spider) Filistatidae (crevice weaver) Sicariidae (recluse spider) Scytodidae (spitting... Families Antrodiaetidae (folding trapdoor spider) Atypidae (atypical tarantula) Ctenizidae (trapdoor spider) Cyrtaucheniidae (wafer trapdoor spider) Dipluridae (funnel-web tarantula) Hexathelidae (venomous funnel-web tarantula) Mecicobothriidae (dwarf tarantulas) Theraphosidae (tarantula) The Mygalomorphae, (also called the Orthognatha), are an infraorder of spiders. ... For other uses, see Tarantula (disambiguation). ... Family See text for details. ... Diversity 4 suborders Suborders Cyphophthalmi Eupnoi Dyspnoi Laniatores Harvestmen (also known as daddy long-legs) are eight-legged invertebrate animals belonging to the order Opiliones (formerly Phalangida) in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Genera 80 species in 4 genera See text A palpigrade, commonly known as a microwhip scorpion, is an invertebrate animal belonging to the order Palpigradi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A pseudoscorpion, (also known as a false scorpion or book scorpion), is an invertebrate animal belonging to the order Pseudoscorpionida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A ricinuleid, commonly known as a hooded tickspider, is an invertebrate animal belonging to the order Ricinulei in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A schizomid is an invertebrate animal belonging to the order Schizomida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A scorpion is an invertebrate animal with eight legs belonging to the order Scorpiones in the class Arachnida. ... Families see text The order Solifugae is a group of arachnids, containing more than 1,000 described species in about 140 genera. ... Family Plesiosironidae Pocock 1911 Haptopoda Pocock 1911 is an extinct arachnid order known exclusively from a few specimens from the Upper Carboniferous of the UK. It is monotypic, i. ... Families Geralinuridae Thelyphonidae A uropygid, commonly known as a Whip Scorpion, is an invertebrate animal belonging to the former order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Mites, along with ticks, belong to the subclass Acarina (also known as Acari) and the class Arachnida. ... Families Ixodidae - Hard ticks Argasidae - Soft ticks Nuttalliellidae - ????? ticks Wikispecies has information related to: Ixodoidea Tick is the common name for the small arachnids that, along with other mites, constitute the order Acarina. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Superfamilies Mesostigmata Ixodida Holothyrida Parasitiformes is a suborder consisting mostly of ticks. ...

Acarina

Acarina or Acari are a taxon of arachnids that contains mites and ticks. Its fossil history goes back to the Devonian era. The Devonian era was the time frame in which certain species of animals developed legs. In most modern treatments, the Acari is considered a subclass of Arachnida and is composed of 2-3 orders or superorders: Acariformes, Parasitiformes, and Opilioacariformes. Most acarines are minute to small (e.g. 0.080-1.00 mm), but the giants of the Acari (some ticks and red velvet mites) may reach lengths of 10-20 mm. It is estimated that over 50,000 species have been described (as of 1999) and that a million or more species are currently living. The study of mites and ticks is called acarology.^[6] Image File history File links Download high resolution version (1182x1407, 212 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Tick ... Image File history File links Download high resolution version (1182x1407, 212 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Tick ... Binomial name (Linnaeus, 1758) Ixodes ricinus, known as the sheep tick or castor bean tick is a hard-bodied tick (family Ixodidae) of Europe. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... A taxon (plural taxa), or taxonomic unit, is a grouping of organisms (named or unnamed). ... Mites, along with ticks, belong to the subclass Acarina (also known as Acari) and the class Arachnida. ... Families Ixodidae - Hard ticks Argasidae - Soft ticks Nuttalliellidae - ????? ticks Wikispecies has information related to: Ixodoidea Tick is the common name for the small arachnids that, along with other mites, constitute the order Acarina. ... For the Celtic language, see Southwestern Brythonic language; for the residents of the English county, see Devon. ... In object-oriented programming, subclass is a class that is derived from another class or classes. ... Orders Acarina Amblypygi Araneae Opiliones Palpigradi Pseudoscorpionida Ricinulei Schizomida Scorpiones Solifugae Uropygi The arachnids, Arachnida, are a class of invertebrate animals in the subphylum Chelicerata. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Superfamilies Mesostigmata Ixodida Holothyrida Parasitiformes is a suborder consisting mostly of ticks. ... Events of 2008: (EMILY) Me Lesley and MIley are going to China! This article is about the year. ... Look up acarology in Wiktionary, the free dictionary. ...

Only the faintest traces of primary segmentation remain in mites, the prosoma and opisthosoma being insensibly fused, and a region of flexible cuticle (the cirumcapitular furrow) separates the chelicerae and pedipalps from the rest of the body. This anterior body region is called the capitulum or gnathosoma and is also found in the Ricinulei. The remainder of the body is called the idiosoma and is unique to mites. Most adult mites have four pairs of legs, like other arachnids, but some have fewer. For example, gall mites like Phyllocoptes variabilis (superfamily Eriophyioidea) have a wormlike body with only two pairs of legs; some parasitic mites have only one or three pairs of legs in the adult stage. Larval and prelarval stages have a maximum of three pairs of legs; adult mites with only three pairs of legs may be called 'larviform'. An inflorescence is a group or cluster of flowers on a branch of a plant. ... A ricinuleid, commonly known as a hooded tickspider, is an invertebrate animal belonging to the order Ricinulei in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Diversity 3 species Species See text. ... Orders Acarina Amblypygi Araneae Opiliones Palpigradi Pseudoscorpionida Ricinulei Schizomida Scorpiones Solifugae Uropygi The arachnids, Arachnida, are a class of invertebrate animals in the subphylum Chelicerata. ... Genera include Abacarus Aberoptus Acalitus Acaphylla Acaphyllisa Acaralox Acarelliptus Acaricalus Aceria Achaetocoptes Acritonotus Aculochetus Aculodes Aculops Aculus Adenoptus Aequsomatus Anthocoptes Bariella Boczekiana Brachendus Calacarus Calepitrimerus Callyntrotus Cecidophyes Cecidophyopsis Cisaberiptus Colomerus Coptophylla Cosetacus Criotacus Cupacarus Cymoptus Dichopelmus Ditrymacus Epitrimerus Eriophyes Gilarovella Glyptacus Keiferella Leipothrix Liroella Mesalox Metaculus Monochetus Neooxycenus Neotegonotus Oxycenus...

Acarine ontogeny consists of an egg, a prelarval stage (often absent), a larval stage (hexapod except in Eriophyoidea which have only 2 pairs of legs), and a series of nymphal stages. Larvae (and prelarvae) have a maximum of 3 pairs of legs (legs are often reduced to stubs or absent in prelarvae); legs IV are added at the first nymphal stage. Ontogeny (also ontogenesis or morphogenesis) describes the origin and the development of an organism from the fertilized egg to its mature form. ...

Acarines live in practically every habitat, and include aquatic (freshwater and sea water) and terrestrial species. They outnumber other arthropods in the soil organic matter and detritus. Many are parasitic, and they affect both vertebrates and invertebrates. Most parasitic forms are external parasites, while the free living forms are generally predaceous and may even be used to control undesirable arthropods. Others are detritivores that help to break down forest litter and dead organic matter such as skin cells. Others still are plant feeders and may damage crops. Damage to crops is perhaps the most costly economic effect of mites, especially by the spider mites and their relatives (Tetranychoidea), earth mites (Penthaleidae), thread-footed mites (Tarsonemidae) and the gall and rust mites (Eriophyoidea). Some parasitic forms affect humans and other mammals, causing damage by their feeding, and can even be vectors of diseases such as scrub typhus and rickettsial pox. A well-known effect of mites on humans is their role as an allergen and the stimulation of asthma in people affected by the repiratory disease. The use of predatory mites (e.g. Phytoseiidae) in pest control and herbivorous mites that attack weeds are also of importance. An unquantified, but major positive contribution of the Acari is their normal functioning in ecosystems, especially their roles in the decomposer subsystem ^[6]. An ecoregion, sometimes called a bioregion, is a relatively large area of land or water that contains a geographically distinct assemblage of natural communities. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... Organic material or organic matter is informally used to denote a material that originated as a living organism; most such materials contain carbon and are capable of decay. ... In biology, detritus is organic waste material from decomposing dead plants or animals. ... This article is about a relationship between organisms. ... This article does not cite any references or sources. ... Invertebrate is an English word that describes any animal without a spinal column. ... Predator and Prey redirect here. ... A dung beetle rolling a ball of dung Detritivores (also known as saprophages, detrivores or detritus feeders) are organisms that recycle detritus (decomposing organic material), returning it into the food chain. ... Blanket of reddish-brown ponderosa pine needles covering the ground. ... This article is about the organ. ... A deer and two fawns feeding on some foliage Herbivory is a form of predation in which an organism known as an herbivore, consumes principally autotrophs[1] such as plants, algae and photosynthesizing bacteria. ... For other uses, see crop (disambiguation). ... Genera See text. ... Only a limited number tarsonemid genera, Steneotarsonemeus, Polyphagotarsonemus, Phytonemus, Floridotarsonemus and Tarsonemus, are known to feed on higher plants while most species in this family feed on the thin walled mycelia of fungi or possibly algal bodies (Jeppson, 1975). ... Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ... Subclasses & Infraclasses Subclass â€ Allotheria* Subclass Prototheria Subclass Theria Infraclass â€ Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... In epidemiology, a vector is an organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another. ... Scrub typhus is a form of typhus caused by Orientia tsutsugamushi and transmitted by chiggers, which are found in areas of heavy scrub vegetation. ... Species Rickettsia felis Rickettsia prowazekii Rickettsia rickettsii Rickettsia typhi Rickettsia conorii Rickettsia africae etc. ... An allergen is any substance (antigen), most often eaten or inhaled, that is recognized by the immune system and causes an allergic reaction. ... Subfamilies [1] Amblyseiinae Phytoseiinae Typhlodrominae Phytoseiidae is a family of mites which feed on thrips and other mite species. ... A crop duster applies low-insecticide bait that is targeted against Western corn rootworms Pest control refers to the regulation or management of another species defined as a pest, usually because it is believed to be detrimental to a persons health, the ecology or the economy Pest control is... Yellow starthistle, a thistle native to southern Europe and the Middle East that is an invasive weed in parts of North America. ... A coral reef near the Hawaiian islands is an example of a complex marine ecosystem. ...

Amblypygi

Amblypygids are also known as tailless whip scorpions or cave spiders. Approximately 5 families, 17 genera and 136 species have been described. They are found in tropical and subtropical regions worldwide. Some species are subterranean; many are nocturnal. During the day, they may hide under logs, bark, stones, or leaves. They prefer a humid environment. Amblypygids may range from 5 to 40 mm. Their bodies are broad and highly flattened and the first pair of legs (the first walking legs in most arachnid orders) are modified to act as sensory organs. (Compare solifugids, uropygids, and schizomids.) These very thin modified legs can extend several times the length of body. They have no silk glands or venomous fangs, but can have prominent pincer-like pedipalps. Amblypygids often move about sideways on their six walking legs, with one "whip" pointed in the direction of travel while the other probes on either side of them. Prey are located with these "whips", captured with pedipalps, then torn to pieces with chelicerae. Fossilised amblypygids have been found dating back to the Carboniferous period. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... An amblypygid is an invertebrate animal belonging to the order Amblypygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A noontime scene from the Philippines on a day when the Sun is almost directly overhead. ... 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 Capricorn, at latitude 23. ... A bat illustrating nocturnal features. ... A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... Genera Eremobates Syndaesia A Solifugid (plural form Solifugae) is an arachnid belonging to the order Solifugae. ... Families Geralinuridae Thelyphonidae A uropygid, commonly known as a Whip Scorpion, is an invertebrate animal belonging to the former order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A schizomid is an invertebrate animal belonging to the order Schizomida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... For other uses of this word, see Silk (disambiguation). ... Wasp sting, with droplet of venom Venom (literally, poison of animal origin) is any of a variety of toxins used by animals, for the purpose of defense and hunting. ... Thelyphonida, in dorsal view, with pedipalps highlighted in green Pedipalps, the second pair of appendages of the cephalothorax in Arachnida, is homologous with mandibles in Crustacea, and corresponding to the mandibles of insects. ... Types of chelicerae: jackknife (in green), scissor (in blue) and 3-segmented chelate (in red) The Chelicerae are mouth parts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata (horseshoe crabs), and Pycnogonida (sea spiders). ... For other uses, see Fossil (disambiguation). ... The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359. ...

Amblypygids, particularly the species Phrynus marginemaculatus and Damon diadema, are thought to be one of the few species of arachnids that show signs of social behavior. Research conducted at Cornell University by entomologists suggests that mother amblypygids comfort their young by gently caressing the offspring with her feelers. Further, when two or more siblings were placed in an unfamiliar environment, such as a cage, they would seek each other out and gather back in a group ^[7] In biology, psychology and sociology social behavior is behavior directed towards, or taking place between, members of the same species. ... Cornell redirects here. ...

Araneae

Spiders are the most familiar of the arachnids, and the most numerous, if only described species are counted. All spiders produce silk, a thin, strong protein strand extruded by the spider from spinnerets most commonly found on the end of the abdomen. Many species use it to trap insects in webs, although there are 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, even flying, among other applications. Image File history File links Download high-resolution version (748x1006, 235 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Spider Wikipedia:List of images/Nature/Animals/Spiders Araneoidea ... Image File history File links Download high-resolution version (748x1006, 235 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Spider Wikipedia:List of images/Nature/Animals/Spiders Araneoidea ... Binomial name Araneus diadematus Clerck, 1757 The European garden spider (Araneus diadematus, cross spider) is a very common and well-known orb-weaver spider in Western Europe. ... For other uses, see Spider (disambiguation). ... Spider silk is a fibre secreted by spiders. ... A representation of the 3D structure of myoglobin showing coloured alpha helices. ... A spinneret is a spiders silk spinning organ. ... Spiders web redirects here. ... Ballooning is a term to describe the way many spider species disperse through the air. ...

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 and liquefy prey. Only about 200 species, however, have bites that can pose health problems to humans.^[8] Many larger species' bites may be painful, but will not produce lasting health concerns. Genera Ariston Astavakra Conifaber Daramulunia Hyptiotes Lubinella Miagrammopes Octonoba Orinomana Philoponella Polenecia Purumitra Siratoba Sybota Tangaroa Uloborus Waitkera Zosis The hackled orbweavers (family Uloboridae) have the special distinction of being non-venomous spiders. ... Genera see text The Holarchaeidae are a spider family with only two described species in one genus. ... The Liphistiidae are the most primitive living spiders, placed in their own suborder, called the Mesothelae. ... Wasp sting, with droplet of venom Venom (literally, poison of animal origin) is any of a variety of toxins used by animals, for the purpose of defense and hunting. ... Chelicerae of a black wishbone (Nemesiidae) spider, a mygalomorph Spiders are widely known, and feared by some, for their capability of biting human beings. ...

Spiders are found all over the world, from the tropics to the Arctic, with some extreme species even living underwater in silken domes they supply with air, and on the tops of the highest mountains.

Haptopoda

Haptopoda is an extinct order known exclusively from a few specimens from the Upper Carboniferous of the United Kingdom. It is monotypic, i. e., has only one species, Plesiosiro madeleyi Pocock 1911. Relationships with other arachnids are obscure, but closest relatives may be the Amblypygi, Thelyphonida and Schizomida of the tetrapulmonate clade ^[9] Family Plesiosironidae Pocock 1911 Haptopoda Pocock 1911 is an extinct arachnid order known exclusively from a few specimens from the Upper Carboniferous of the UK. It is monotypic, i. ... The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359. ... An amblypygid is an invertebrate animal belonging to the order Amblypygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families Geralinuridae Thelyphonidae A uropygid, commonly known as a whip scorpion, is an invertebrate animal belonging to the former order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families Calcitronidae â€ Petrunkevitch, 1945b Hubbardiidae Cook, 1899 Protoschizomidae Rowland, 1975 A schizomid is an invertebrate animal belonging to the order Schizomida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ...

Opiliones

Opiliones (better known as "harvestmen" or ""daddy longlegs"") are arachnids which are harmless to people and are known for their exceptionally long walking legs, compared to their body size. As of 2005, over 6,300 species of Phalangids have been discovered worldwide. The order Opiliones can be divided in four suborders: Cyphophthalmi, Eupnoi, Dyspnoi and Laniatores. Well-preserved fossils have been found in the 400-million year old Rhynie cherts of Scotland, which look surpringly modern, indicating that the basic structure of the harvestmen hasn't changed much since then. Their closest relatives are probably the mites (Acari). Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... Binomial name (Meade, 1855) Synonyms Opilio agrestis Oligolophus ephippiger Paroligolophus agrestis is a species of harvestman. ... Diversity 4 suborders Suborders Cyphophthalmi Eupnoi Dyspnoi Laniatores Harvestmen (also known as daddy long-legs) are eight-legged invertebrate animals belonging to the order Opiliones (formerly Phalangida) in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... 2005 is a common year starting on Saturday of the Gregorian calendar. ... Diversity 6 families, > 100 species Superfamilies Stylocelloidea Ogoveoidea Sironoidea The Cyphophthalmi are a suborder of harvestmen, with about 36 genera, and more than hundred described species. ... Diversity 6 families, > 1,700 species Superfamilies Caddoidea Phalangioidea The Eupnoi are a suborder of harvestmen, with more than 200 genera, and about 1,700 described species. ... Diversity 7 families, > 300 species Superfamilies Ischyropsalidoidea Nemastomatoidea Troguloidea The Dyspnoi are a suborder of harvestmen, with about 32 genera, and about 320 described species. ... Laniatores is the largest suborder of the arachnid order Opiliones with over 4,000 species worldwide. ... Rhynie chert is the name for fossiliferous material from a uniquely well-preserved layer in one site near the village of Rhynie, Aberdeenshire, Scotland. ... Families Tetranychidae - Spider mites Eriophyidae - Gall mites Sarcoptidae - Sarcoptic Mange mites The mites and ticks, order Acarina or Acari, belong to the Arachnida and are among the most diverse and successful of all the invertebrate groups, although some way behind the insects. ...

The difference between harvestmen and spiders is that in harvestmen the two main body sections (the abdomen with ten segments and cephalothorax, or prosoma and opisthosoma) are nearly joined, so that they appear to be one oval structure. In more advanced species, the first five abdominal segments are often fused into a dorsal shield called the scutum, which is normally fused with the carapace. Sometimes this shield is only present in males. The two most posterior abdominal segments can be reduced or separated in the middle on the surface to form two plates lying next to each other. The second pair of legs are longer than the others and works as antennae. They have a single pair of eyes in the middle of their heads, orientated sideways. They have a pair of prosomatic scent glands that secrete a peculiar smelling fluid when disturbed. Harvestmen do not have silk glands and do not possess poison glands, posing absolutely no danger to humans. They breathe through tracheae. Between the base of the fourth pair of legs and the abdomen a pair of spiracles are located, one opening on each side. In more active species, spiracles are also found upon the tibia of the legs. They have a gonopore on the ventral cephalothorax, and the copulation is direct as the male has a penis (while the female has an ovipositor). The abdomen in a human and an ant. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... The opisthosoma is the posterior portion of the arachnids body behind the prosoma. ... This oval, with only one axis of symmetry, resembles a chicken egg. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Many terrestrial arthropods have evolved a closed respiratory system composed of spiracles, tracheae, and tracheoles to transport metabolic gasses to and from tissue. ... Spiracles are small openings on the surface of animals that usually lead to respiratory systems. ... This article is about the vertebrate bone. ... A genital pore in some invertebrates and especially some insects. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... A pair of lions copulating in the Maasai Mara, Kenya. ... The penis (plural penises, penes) is an external male sexual organ. ... This article does not cite any references or sources. ...

Typical body length does not exceed 7 mm (about ¼ in) even in the largest species. However, leg span is much larger and can exceed 160 mm (over 6 in). Most species live for a year. Many species are omnivorous, eating primarily small insects and all kinds of plant material and fungi; some are scavengers of the decays of any dead animal, bird dung and other fecal material. Mating involves direct copulation, rather than the deposition of a spermatophore. They are mostly nocturnal and coloured in hues of brown, although there are a number of diurnal species which have vivid patterns in yellow, green and black with varied reddish and blackish mottling and reticulation. A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... An inch (plural: inches; symbol or abbreviation: in or, sometimes, â€³ - a double prime) is the name of a unit of length in a number of different systems, including English units, Imperial units, and United States customary units. ... Omnivores are organisms that consume both plants and animals. ... For the fictional character, see Fungus the Bogeyman. ... For a person who scavenges, see Waste picker. ... Feces (also spelled faeces in British English, or fæces) are semi-solid waste products from the digestive tract expelled through the anus (or cloaca) during defecation. ... IT FEELS REALLY GOOD IF YOU IMATATE THE ANIMALS. LOL! â€œMountingâ€ redirects here. ... A pair of lions copulating in the Maasai Mara, Kenya. ... A spermatophore is a capsule or mass created by males of various invertebrate species, containing spermatozoa and transferred in entirety to the female during sex. ... A bat illustrating nocturnal features. ... A diurnal animal (dÄ«-ÅrnÉ™l) is an animal that is active during the daytime and sleeps during the night. ...

Palpigradi

Palpigradi, commonly known as "microwhip scorpions", are tiny cousins of the uropygid, or whip scorpion, no more than 3 mm in length. They have a thin, pale, segmented carapace which terminates in a whip-like flagellum, made up of 15 segments. The carapace is divided into two plates between the third and fourth leg set. They have no eyes. Some species have three pairs of book lungs, while others have no lungs at all. Approximately 80 species of Palpigradi have been described worldwide, all in the family Eukoeneniidae, which contains four genera. Genera 80 species in 4 genera See text A palpigrade, commonly known as a microwhip scorpion, is an invertebrate animal belonging to the order Palpigradi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families Geralinuridae Thelyphonidae A uropygid, commonly known as a Whip Scorpion, is an invertebrate animal belonging to the former order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... There are three orders of whip scorpions in the class Arachnida: Amblypygi - tailless whip scorpions Palpigradi - micro whip scorpions (less than 3mm) Uropygi - whip scorpions In addition, members of the Schizomida also also sometimes called micro whip scorpions. See also: Pseudoscorpionida - pseudoscorpions Scorpiones - scorpions Schizomida Solifugae - wind scorpions ... A book lung is a type of respiration organ used for atmospheric gas exchange and is found in arachnids, such as scorpions and spiders. ...

They are believed to be predators like their larger relatives, feeding on minuscule insects in their habitat. Their mating habits are unknown, except that they lay only a few relatively large eggs at a time. Microwhip scorpions need a damp environment to survive, and they always hide from light, so they are commonly found in the moist earth under buried stones and rocks. They can be found on every continent, except in Arctic and Antarctic regions.

Phalangiotarbida

Phalangiotarbi (Haase, 1890) is an extinct arachnid order known exclusively from the Upper Carboniferous of Europe and North America. Family See text for details. ... Haase may refer to: Barry Haase, Australian politician Curt Haase, German soldier Ernie Haase, American tenor Friedrich Haase, German actor Friedrich Gottlob Haase, German classical scholar Hugo Haase, German politician John Haase, German dentist and author Madeline Haase, American artist Mandy Haase, German hockey player Werner Haase, German professor of... The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359. ...

The affinities of phalangiotarbids are obscure, with most authors favouring affinities with Opiliones (harvestmen) and/or Acari (mites and ticks). Phalangiotarbida has been recently proposed to be sister group to (Palpigradi+Tetrapulmonata): the taxon Megoperculata sensu Shultz (1990). (Pollitt et al., 2004).

Pseudoscorpions

Pseudoscorpions are small arthropods with a flat, pear-shaped body and pincers that resemble those of scorpions. They range from 2 to 8 mm (¹⁄₁₂ to ⅓ inch) in length ^[10]. The opisthosoma is made up of twelve segments, each guarded by plate-like tergites above and sternites below. The abdomen is short and rounded at the rear, rather than extending into a segmented tail and stinger like true scorpions. The colour of the body can be yellowish-tan to dark-brown, with the paired claws often a contrasting colour. They may have two, four or no eyes. They have two very long palpal chelae (pedipalps or pincers) which strongly resemble the pincers found on a scorpion. The pedipalps generally consist of an immobile "hand" and "finger", with a separate movable finger controlled by an adductor muscle. A venom gland and duct are usually located in the mobile finger; the poison is used to capture and immobilise the pseudoscorpion's prey. During digestion, pseudoscorpions pour a mildly corrosive fluid over the prey, then ingest the liquefied remains. Pseudoscorpions spin silk from a gland in their jaws to make disk-shaped cocoons for mating, molting, or waiting out cold weather. Another trait they share with their closest relatives, the spiders, is breathing through spiracles. Most spiders have one pair of spiracles, and one of book lungs, but pseudoscorpions do not have book lungs. Image File history File links Download high resolution version (808x616, 306 KB) File links The following pages link to this file: Pseudoscorpion ... Image File history File links Download high resolution version (808x616, 306 KB) File links The following pages link to this file: Pseudoscorpion ... A pseudoscorpion, (also known as a false scorpion or book scorpion), is an arachnid belonging to the order Pseudoscorpionida, also known as Pseudoscorpiones or Chelonethida. ... Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ... A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... An inch (plural: inches; symbol or abbreviation: in or, sometimes, â€³ - a double prime) is the name of a unit of length in a number of different systems, including English units, Imperial units, and United States customary units. ... A tergum (pl. ... The sternum (pl. ... Thelyphonida, in dorsal view, with pedipalps highlighted in green Pedipalps, the second pair of appendages of the cephalothorax in Arachnida, is homologous with mandibles in Crustacea, and corresponding to the mandibles of insects. ... ... It has been suggested that Snake poison be merged into this article or section. ... The tough brown cocoon of an Emperor Gum Moth. ... For other uses, see Spider (disambiguation). ... Spiracles are small openings on the surface of animals that usually lead to respiratory systems. ... A book lung is a rudimentary type of lung found in arachnids, such as scorpions and spiders, and in horseshoe crabs. ...

There are more than 2,000 species of pseudoscorpions recorded. They range worldwide, even in temperate to cold regions, but have their most dense and diverse populations in the tropics and subtropics. The fossil record of pseudoscorpions dates back over 380 million years, to the Devonian period, near the time when the first land-animal fossils appear. A noontime scene from the Philippines on a day when the Sun is almost directly overhead. ... 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 Capricorn, at latitude 23. ... For the Celtic language, see Southwestern Brythonic language; for the residents of the English county, see Devon. ...

During the elaborate mating dance, the male of some pseudoscorpion species pulls a female over a spermatophore previously laid upon a surface ^[11]. In other species, the male also pushes the sperm into the female genitals using the forelegs ^[12].The female carries the fertilised eggs in a brood pouch attached to her abdomen, and the young ride on the mother for a short time after they hatch ^[10]. Up to two dozen young are hatched in a single brood; there may be more than one brood per year. The young go through three molts over the course of several years before reaching adulthood. Adult pseudoscorpions live 2 to 3 years. They are active in the warm months of the year, overwintering in silken coccoons when the weather grows cold. Sevenspotted Lady Beetles mating In biology, mating is the pairing of opposite-sex or hermaphroditic internal fertilization animals for copulation and, in social animals, also to raise their offspring. ... A spermatophore is a capsule or mass created by males of various invertebrate species, containing spermatozoa and transferred in entirety to the female during sex. ... A marsupium is the Latin word for a (brood) pouch in several animal groups. ... The abdomen in a human and an ant. ... Look up Brood in Wiktionary, the free dictionary. ... Ecdysis is the molting of the cuticula in arthropods and related groups (Ecdysozoa). ...

Pseudoscorpions are generally beneficial to humans since they prey on clothes moth larvae, carpet beetle larvae, booklice, ants, mites, and small flies. They are small and inoffensive, and are rarely seen due to their size. They usually enter the home by "riding along" with larger insects (known as phoresy), or are brought in with firewood. They are often observed in bathrooms or laundry rooms, since they seek humidity. They may sometimes be found feeding on mites under the wing covers of certain beetles. For other uses, see Moths. ... Genera many, see text Wikispecies has information related to: Skin beetle The skin beetles or Dermestidae (Gyllenhaal 1808) are a beetle family. ... Suborders Trogiomorpha (5 families) Troctomorpha (8 families) Psocomorpha (22 families) Psocoptera are an order of insects that are commonly known as booklice or barklice. ... For other uses, see Ant (disambiguation). ... Mites, along with ticks, belong to the subclass Acarina (also known as Acari) and the class Arachnida. ... Suborders Nematocera (includes Eudiptera) Brachycera Diptera (di - two, ptera - wings), or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. ... In ecology, commensalism is an interaction between two living organisms, where one creature benefits and the other is neither harmed nor helped. ...

Ricinulei

Riniculei (hooded tickspiders) are 5–10 mm long. Their most notable feature is a "hood" which can be raised and lowered over the head; when lowered, it covers the mouth and the chelicerae. Ricinulei have no eyes. The pedipalps end in pincers that are small relative to their bodies, when compared to those of the related orders of scorpions and pseudoscorpions. The heavy-bodied abdomen forms a narrow pedicel, or waist, where it attaches to the prosoma. In males, the third pair of legs are modified to form copulatory organs. Malpighian tubules and a pair of coxal glands make up the excretory system. They have no lungs, as gas exchange takes place through the trachea. A ricinuleid, commonly known as a hooded tickspider, is an invertebrate animal belonging to the order Ricinulei in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A millimetre (American spelling: millimeter, symbol mm) is an SI unit of length that is equal to one thousandth of a metre. ... Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ... A pseudoscorpion, (also known as a false scorpion or book scorpion), is an arachnid belonging to the order Pseudoscorpionida, also known as Pseudoscorpiones or Chelonethida. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... The Malpighian tubules are the insects main organ of excretion and osmoregulation, helping them to maintain water and electrolyte balance. ...

Ricinulei are predators, feeding on other small arthropods. Little is known about their mating habits; the males have been observed using their modified third leg to transfer a spermatophore to the female. The eggs are carried under the mother's hood, until the young hatch into six-legged "larva", which later molt into their adult forms. Ricinulei require moisture to survive. Approximately 57 species of ricinuleids have been described worldwide, all in a single family which contains 3 genera. A spermatophore is a capsule or mass created by males of various invertebrate species, containing spermatozoa and transferred in entirety to the female during sex. ... Ecdysis is the molting of the cuticula in arthropods and related groups (Ecdysozoa). ...

Schizomida

Schizomida is an order of arachnids which tend to live in the top layer of soils. Schizomids present the prosoma covered by a large protopeltidium and smaller, paired, mesopeltidia and metapeltidia. There are no eyes. The opisthosoma is a smooth oval of 12 recognisable somites. The first is reduced and forms the pedicel. The last three are much constricted, forming the pygidium. The last somite bears the flagellum, which in this order is short and consists of not more than four segments. Families Calcitronidae â€ Petrunkevitch, 1945b Hubbardiidae Cook, 1899 Protoschizomidae Rowland, 1975 A schizomid is an invertebrate animal belonging to the order Schizomida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... In scientific classification used in biology, the order (Latin: ordo, plural ordines) is a rank between class and family (termed a taxon at that rank). ... Peltidium is a prodorsal shield found in animals of the Subphylum Chelicerata, in the Phylum Arthropoda. ... Peltidium is a prodorsal shield found in animals of the Subphylum Chelicerata, in the Phylum Arthropoda. ... The opisthosoma is the posterior portion of the arachnids body behind the prosoma. ... In anatomy, the pedicle (also spelled pedicel) is the segment between the transverse process and the vertebral body. ... The pygidium is the posterior body part or shield of crustaceans, some insects, and trilobites. ...

The name means "split or cleaved middle", referring to the way the cephalothorax is divided into two separate plates. Like the related orders Uropygi, Amblypygi, and Solpugida, the schizomids use only six legs for walking, having modified their first two legs to serve as sensory organs. They also have large well-developed pedipalps (pincers) just behind the sensory legs. The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... Families Geralinuridae Thelyphonidae A uropygid, commonly known as a Whip Scorpion, is an invertebrate animal belonging to the former order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... An amblypygid is an invertebrate animal belonging to the order Amblypygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Genera Eremobates Syndaesia A Solifugid (plural form Solifugae) is an arachnid belonging to the order Solifugae. ...

Scorpions

Scorpions are characterised by a metasoma (tail) comprising six segments, the last containing the scorpion's anus and bearing the telson (the sting). The telson, in turn, consists of the vesicle, which holds a pair of venom glands and the hypodermic aculeus, the venom-injecting barb. The abdomen's front half, the mesosoma, is made up of six segments. The first segment contains the sexual organs as well as a pair of vestigial and modified appendages forming a structure called the genital operculum. The second segment bears a pair of featherlike sensory organs known as the pectines; the final four segments each contain a pair of book lungs. The mesosoma is armored with chitinous plates, known as tergites on the upper surface and sternites on the lower surface. Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... There are very few or no other articles that link to this one. ... Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ... This article is about the bodily orifice. ... The telson is the last division of the body of a crustacean. ... It has been suggested that this article or section be merged with Venom. ... In cell biology, a vesicle is a relatively small and enclosed compartment, separated from the cytosol by at least one lipid bilayer. ... Wasp sting, with droplet of venom Venom (literally, poison of animal origin) is any of a variety of toxins used by animals, for the purpose of defense and hunting. ... The word barb can have many meanings: Look up barb in Wiktionary, the free dictionary. ... A sex organ, or primary sexual characteristic, as narrowly defined, is any of the anatomical parts of the body which are involved in sexual reproduction and constitute the reproductive system in a complex organism; in mammals, these are: Female: Bartholins glands, cervix, clitoris, Fallopian tubes, labia, ovaries, Skenes... A book lung is a type of respiration organ used for atmospheric gas exchange and is found in arachnids, such as scorpions and spiders. ... Armor or armour (see spelling differences) is protective clothing intended to defend its wearer from intentional harm in combat and military engagements, typically associated with soldiers. ... Structure of the chitin molecule, showing two of the N-Acetylglucosamine units that repeat to form long chains in beta-1,4 linkage. ... A tergum (pl. ... The sternum (pl. ...

The cuticle of scorpions is covered with hairs in some places that act like balance organs. An outer layer that makes them fluorescent green under ultraviolet light is called the hyaline layer. Newly molted scorpions do not glow until after their cuticle has hardened. The fluoresent hyaline layer can be intact in fossil rocks that are hundreds of millions of years old. Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ...

Scorpions are opportunistic predators of small arthropods and insects. They use their chela (pincers) to catch the prey initially. Depending on the toxicity of their venom and size of their claws, they will then either crush the prey or inject it with neurotoxic venom. The neurotoxins consist of a variety of small proteins as well as sodium and potassium cations, which serve to interfere with neurotransmission in the victim. Scorpions use their venom to kill or paralyze their prey so that it can be eaten; in general it is fast acting, allowing for effective prey capture. Scorpion venoms are optimised for action upon other arthropods and therefore most scorpions are relatively harmless to humans; stings produce only local effects (such as pain, numbness or swelling). A few scorpion species, however, mostly in the family Buthidae, can be dangerous to humans. The scorpion which is responsible for the most human deaths is the Androctonus australis, or fat-tailed scorpion of North Africa. The toxicity of A. australis's venom is roughly half that of L. quinquestriatus, but since A. australis injects quite a bit more venom into its prey, it is the most deadly to humans. Human deaths normally occur in the young, elderly, or infirm; scorpions are generally unable to deliver enough venom to kill healthy adults. Some people, however may be allergic to the venom of some species, in which case the scorpion's sting can more likely kill. A primary symptom of a scorpion sting is numbing at the injection site, sometimes lasting for several days. It has been found that scorpions have two types of venom: a translucent, weaker venom designed to stun only, and an opaque, more potent venom designed to kill heavier threats ^[13]^[14]. The term neurotoxic is used to describe a substance, condition or state that damages the nervous system and / or brain, usually by killing neurons. ... A representation of the 3D structure of myoglobin showing coloured alpha helices. ... A cation is an ion with positive charge. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... Genera Ananteris Androctonus Centruroides Leiurus Odonturus Parabuthus â€¦ Buthidae is a family of scorpions. ... Species 13 species, see article. ... Northern Africa (UN subregion) geographic, including above North Africa or Northern Africa is the northernmost region of the African continent, separated by the Sahara from Sub-Saharan Africa. ...

Unlike the majority of Arachnida species, scorpions are viviparous. The young are born one by one, and the brood is carried about on its mother's back until the young have undergone at least one moult.^[15] The young generally resemble their parents, requiring between five and seven moults to reach maturity. Scorpions have quite variable lifespans and the lifespan of most species is not known. The age range appears to be approximately 4-25 years (25 years being the maximum reported life span in the species H. arizonensis). They are nocturnal and fossorial, finding shelter during the day in the relative cool of underground holes or undersides of rocks and coming out at night to hunt and feed. Scorpions prefer to live in areas where the temperatures range from 20°C to 37 °C (68°F to 99 °F), but may survive in the temperature range of 14 °C to 45 °C (57 °F to 113 °F) ^[16]^[17]. A viviparous animal is an animal employing vivipary, a method of reproduction in which the embryo develops inside the body of the mother from which it gains nourishment, and not from an egg. ... Ecdysis is the molting of the cuticula in arthropods and related groups (Ecdysozoa). ... A fossorial is an organism that is adapted to digging and life underground such as the mole salamanders Ambystomatidae. ... For other uses, see Celsius (disambiguation). ... For other uses, see Fahrenheit (disambiguation). ...

Scorpions have been found in many fossil records, including coal deposits from the Carboniferous Period and in marine Silurian deposits. They are thought to have existed in some form since about 425–450 million years ago. They are believed to have an oceanic origin, with gills and a claw like appendage that enabled them to hold onto rocky shores or seaweed. The Carboniferous is a major division of the geologic timescale that extends from the end of the Devonian period, about 340 million years ago (mya), to the beginning of the Permian period, about 280 mya. ... For other uses, see Silurian (disambiguation). ...

Solifugae

Solifugae is a group of 900 species of arachnids, commonly known as camel spiders, wind scorpions, and sun spiders. The name derives from Latin, and means those that flee from the sun. Most Solifugae live in tropical or semitropical regions where they inhabit warm and arid habitats, but some species have been known to live in grassland or forest habitats. The most distinctive feature of Solifugae is their large chelicerae. Each of the two chelicerae are composed of two articles forming a powerful pincer; each article bears a variable number of teeth. Males in all families but Eremobatidae possess a flagellum on the basal article of the chelicera. Solifugae also have long pedipalps, which function as sense organs similar to insects' antennae and give the appearance of the two extra legs. Pedipalps terminate in eversible adhesive organs. Image File history File linksMetadata Size of this preview: 800 Ã— 560 pixelsFull resolution (2252 Ã— 1576 pixel, file size: 1. ... Image File history File linksMetadata Size of this preview: 800 Ã— 560 pixelsFull resolution (2252 Ã— 1576 pixel, file size: 1. ... Families see text The order Solifugae is a group of arachnids, containing more than 1,000 described species in about 140 genera. ... For other uses, see Latins and Latin (disambiguation). ... Types of chelicerae: jackknife (in green), scissor (in blue) and 3-segmented chelate (in red) The Chelicerae are mouth parts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata (horseshoe crabs), and Pycnogonida (sea spiders). ... Species Eremobates is a genus of arachnids of the order Solifugae. ... For the insect anatomical structure, see Antenna (biology). ... Thelyphonida, in dorsal view, with pedipalps highlighted in green Pedipalps, the second pair of appendages of the cephalothorax in Arachnida, is homologous with mandibles in Crustacea, and corresponding to the mandibles of insects. ... Insects display a wide variety of antennal shapes. ...

Solifugae are carnivorous or omnivorous, with most species feeding on termites, darkling beetles, and other small arthropods; however, solifugae have been videotaped consuming larger prey such as lizards. Prey is located with the pedipalps and killed and cut into pieces by the chelicerae. The prey is then liquefied and the liquid ingested through the pharynx. Reproduction can involve direct or indirect sperm transfer; when indirect, the male emits a spermatophore on the ground and then inserts it with his chelicerae in the female's genital pore. Carnivorism redirects here. ... Crows are omnivores. ... Families Mastotermitidae Kalotermitidae Termopsidae Hodotermitidae Rhinotermitidae Serritermitidae Termitidae Termites, sometimes known as white ants, are a group of social insects usually classified at the taxonomic rank of order Isoptera. ... Subfamilies Lagriinae Phrenapatinae Pimeliinae Diaperinae Hypophloeinae Opatrinae Tenebrioninae Alleculinae Coelometopinae Wikispecies has information related to: Darkling beetle Darkling beetles (also known as Darkening beetles) are a family of beetles found worldwide, estimated at more than 20,000 species. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - trilobites (extinct) Subphylum Chelicerata Arachnida - spiders,scorpions, etc. ... For other uses, see Sperm (disambiguation). ... A spermatophore is a capsule or mass created by males of various invertebrate species, containing spermatozoa and transferred in entirety to the female during sex. ...

Trigonotarbida

The Order Trigonotarbida is an extinct group of arachnids whose fossil record extends from the Silurian to the Lower Permian and are known from several localities in Europe and North America. They superficially resemble spiders, to which they were clearly related. It was once thought that trigonotarbids lacked the silk-producing spinnerets that have apparently been crucial to the spider's evolutionary success, though in recent years at least one fossil find seems to show distinct microtubercles on its hind legs, akin to those used by spiders to direct and manipulate their silk. Family Anthracomartidae Anthracosironidae Trigonotarbidaincertae Palaeocharinidae Eophrynidae Kreischeriidae Trigonotarbidae Lissomartidae Trigonomartidae The trigonotarbids are extinct spider-like animals that belong to the extinct order Trigonotarbida in the class Arachnida. ... In scientific classification used in biology, the order (Latin: ordo, plural ordines) is a rank between class and family (termed a taxon at that rank). ... For other uses, see Fossil (disambiguation). ... For other uses, see Silurian (disambiguation). ... The Permian is a geologic period that extends from about 299. ... For other uses, see Europe (disambiguation). ... North American redirects here. ... For other uses, see Spider (disambiguation). ... Spider silk is a fibre secreted by spiders. ... A spinneret is a spiders silk spinning organ. ... This article is about evolution in biology. ...

These early arachnids seem to have been adapted to stalking prey on the ground. They have been found within the very structure of ground-dwellings plants, possibly where they hid to await their prey. Trigonotarbids are currently the oldest known land arthropods. They lack silk glands on the opisthosoma and cheliceral poison glands, and most likely represented independent offshoots of the Arachnida. The opisthosoma is the posterior portion of the arachnids body behind the prosoma. ...

Uropygi

The Uropygi, commonly known as whip scorpions, range from 25 to 85 mm in length; the largest species, of the genus Mastigoproctus, reaches 85 mm. Like the related orders Schizomida, Amblypygi, and Solifugae, the uropygids use only six legs for walking, having modified their first two legs to serve as antennae-like sensory organs. Many species also have very large scorpion-like pedipalps (pincers). They have one pair of eyes at the front of the cephalothorax and three on each side of the head. Whip scorpions have no poison glands, but they do have glands near the rear of their abdomen that can spray a combination of acetic acid and octanoic acid when they are bothered. Other species spray formic acid or chlorine. As of 2006, over 100 species of uropygids have been described worldwide. Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... (plural Uropygi, also known as Thelyphonida) A uropygid, commonly known as a whip scorpion, vinegarone, or vinegaroon, is an invertebrate animal belonging to the order Uropygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... A schizomid is an invertebrate animal belonging to the order Schizomida in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... An amblypygid is an invertebrate animal belonging to the order Amblypygi in the class Arachnida, in the subphylum Chelicerata of the phylum Arthropoda. ... Families see text The order Solifugae is a group of arachnids, containing more than 1,000 described species in about 140 genera. ... Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... R-phrases , S-phrases , , , Flash point 43 Â°C Related Compounds Related carboxylic; acids Formic acid; Propionic acid; Butyric acid Related compounds acetamide; ethyl acetate; acetyl chloride; acetic anhydride; acetonitrile; acetaldehyde; ethanol; thioacetic acid; acetylcholine; acetylcholinesterase Supplementary data page Structure and properties n, Îµr, etc. ... Caprylic acid is a fatty acid found in coconuts and breast milk. ... Formic acid (systematically called methanoic acid) is the simplest carboxylic acid. ... General Name, symbol, number chlorine, Cl, 17 Chemical series nonmetals Group, period, block 17, 3, p Appearance yellowish green Standard atomic weight 35. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...

Whip scorpions are carnivorous, nocturnal hunters feeding mostly on insects but sometimes on worms and slugs. The prey is crushed between special teeth on the inside of the trochanters (the second segment of the leg) of the front legs. They are valuable in controlling the population of roaches and crickets. Carnivorism redirects here. ...

Males secrete a sperm sac, which is transferred to the female. Up to 35 eggs are laid in a burrow, within a mucous membrane that preserves moisture. Mothers stay with the eggs and do not eat. The white young that hatch from the eggs climb onto their mother's back and attach themselves there with special suckers. After the first molt they look like miniature whip scorpions, and leave the burrow; the mother dies soon after. The young grow slowly, going through three molts in about three years before reaching adulthood. The mucous membranes (or mucosae; singular: mucosa) are linings of mostly endodermal origin, covered in epithelium, and are involved in absorption and secretion. ...

Uropygids are found in tropical and subtropical areas worldwide, usually in underground burrows which they dig with their pedipalps. They may also burrow under logs, rotting wood, rocks, and other natural debris. They enjoy humid, dark places and avoid the light. 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 Capricorn, at latitude 23. ...

References

^ "arachnid". Oxford English Dictionary (2nd edition). (1989).
^ Schmidt 1993: 58
^ Ruppert, E., Fox, R., & Barnes, R. (2007) Invertebrate Zoology: A functional evolutionary approach. 7th Edition. Thomson Learning ISBN 0-03-025982-7
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^ Arthur D. Chapman (2005). Numbers of living species in Australia and the world. Department of the Environment and Heritage. ISBN 0-642-56850-2.
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^ Jeanna Bryner (2007-03-19). Creepy: Spiders Love to Snuggle. LiveScience.
^ James H. Diaz (2004). The global epidemiology, syndromic classification, management, and prevention of spider bites. American Journal of Tropical Medicine and Hygiene 71 (2): 239–250.
^ Dunlop (2000). "The Carboniferous arachnid Plesiosiro", 19th European Colloquium of Arachnology, 17-22 July 2000. University of Aarhus, Denmark.
^ ^a ^b Steve Jacobs. Entomological Notes: Pseudoscorpion Fact Sheet. Pennsylvania State University, Department of Entomology.
^ Peter Weygoldt (1966). Spermatophore Web Formation in a Pseudoscorpion. Science 153 (3744): 1647–1649. doi:10.1126/science.153.3744.1647.
^ Mating biology resolves trichotomy for cheliferoid pseudoscorpions (Pseudoscorpionida, Cheliferoidea) (1993). Journal of Arachnology 21 (2).
^ David Cheng (2005-06-23). Scorpion sting. eMedicine.
^ Jan Ove Rein (1993). Sting use in two species of Parabuthus scorpions (Buthidae). Journal of Arachnology 21: 60–63.
^ W. R. Lourenco (2000). Reproduction in scorpions, with special reference to parthenogenesis. European Arachnology: 71–85.
^ Neil F. Hadley (1970). Water relations of the desert scorpion Hadrurus arizonensis. Journal of Experimental Biology 53: 547–558.
^ K. Hoshino, A. T. V. Moura & H. M. G. de Paula (2006). Selection of environmental temperature by the yellow scorpion Tityus serrulatus Lutz & Mello, 1922 (Scorpiones, Buthidae). J. Venom. Anim. Toxins incl. Trop. Dis. 12 (1): 59–66.

The Oxford English Dictionary print set The Oxford English Dictionary (OED) is a dictionary published by the Oxford University Press (OUP), and is the most successful dictionary of the English language, (not to be confused with the one-volume Oxford Dictionary of English, formerly New Oxford Dictionary of English, of... The Department of the Environment and Heritage (DEH) is a department of the Australian federal government. ... CABI is an abbreviation that may refer to: The California Birth Index database CAB International (Centre for Agriculture and Biosciences International, formerly Commonwealth Agricultural Bureaux International), a non-profit enterprise providing information and databases in the Life Sciences [1] Canadian Association of Business Incubation, a Canadian organization [2] Carol Anderson... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 78th day of the year (79th in leap years) in the Gregorian calendar. ... Aarhus Universitet or the University of Aarhus is a university based in Ã…rhus, Denmark. ... This article is about the state-related university. ... Science is the academic journal of the American Association for the Advancement of Science and is considered one of the worlds most prestigious scientific journals. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... is the 174th day of the year (175th in leap years) in the Gregorian calendar. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ...

Contents

Systematics GA_googleFillSlot("encyclopedia_square");