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Orthognatha
The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to them forming trapdoors over their burrows. Other prominent groups include Australian funnel web spiders and tarantulas, with the latter accounting for around one third of all mygalomorphs. Description This group of spiders comprises mostly heavy-bodied, stout-legged spiders including tarantulas, Australian funnel-web spiders, mouse spiders, and various families of spiders commonly called trapdoor spiders. Like the " primitive" suborder of spiders Mesothelae, they have two pairs of book lungs, and downward-pointing chelicerae. Because of this, the two groups were once believed to be closely related. Later it was realized that the common ancestors of all spiders had these features (a state known as symplesiomorphy). Following the branching in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesothelae
The Mesothelae are a suborder of spiders (order Araneae) that includes a single extant family, Liphistiidae, and a number of extinct families. This suborder is thought to form the sister group to all other living spiders, and to retain ancestral characters, such as a segmented abdomen with spinnerets in the middle and two pairs of book lungs. Members of Liphistiidae are medium to large spiders with eight eyes grouped on a tubercle. They are found only in China, Japan, and southeast Asia. The oldest known Mesothelae spiders are known from the Carboniferous, over 300 million years ago. The Heptathelidae were once considered their own family; today they are considered a subfamily of the Liphistiidae. Description Members of Mesothelae have paraxial chelicerae, two pairs of coxal glands on the legs, eight eyes grouped on a nodule, two pairs of book lungs, and no endites on the base of the pedipalp. Most have at least seven or eight spinnerets near the middle of the abdomen. Lateral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarantula
Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae. , 1,040 species have been identified, with 156 genera. The term "tarantula" is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder (Mygalomorphae) are commonly referred to as "tarantulas" or "false tarantulas". Some of the more common species have become popular in the exotic pet trade. Many New World species kept as pets have setae known as urticating hairs that can cause irritation to the skin, and in extreme cases, cause damage to the eyes. Overview Like all arthropods, the tarantula is an invertebrate that relies on an exoskeleton for muscular support.Pomeroy, R. (2014, February 4). Pub. Real Clear Science, "Spiders, and Their Amazing Hydraulic Legs and Genitalia". Retrieved October 13, 2019, from https://www.realclearscience.com/blog/2013/02/spiders-their-amazing-hydraulic-legs-and-genitals.html. Like other Arachnida, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missulena Bradleyi
''Missulena bradleyi,'' also known as the eastern mouse spider, is a species of spider belonging to the family Actinopodidae. The spider is endemic to the eastern coast of Australia. William Joseph Rainbow described the eastern mouse spider in 1914 from a specimen collected in North Sydney by Henry Houghton Burton Bradley (1845–1918), president of the board of trustees of the Australian Museum at the time. Describing the "beautiful and strikingly marked" specimen as a "decided novelty", Rainbow named it in honour of its collector, whom he stated was the first collector of Australian spiders. Eastern mouse spiders are often mistaken for Australian funnel-web spiders. The females are large and very strong, with powerful chelicerae.Missulena bradleyi Rainbow, 1914 Bradley's Mouse Spider http://www.arachne.org.au/01_cms/details.asp?ID=2587 Their fangs often cross over slightly, while those of Australian funnel-web spiders remain parallel, and the latter often have a drop of venom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venom
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a stinger, in a process called envenomation. Venom is often distinguished from poison, which is a toxin that is passively delivered by being ingested, inhaled, or absorbed through the skin, and toxungen, which is actively transferred to the external surface of another animal via a physical delivery mechanism. Venom has evolved in terrestrial and marine environments and in a wide variety of animals: both predators and prey, and both vertebrates and invertebrates. Venoms kill through the action of at least four major classes of toxin, namely necrotoxins and cytotoxins, which kill cells; neurotoxins, which affect nervous systems; myotoxins, which damage muscles; and haemotoxins, which disrupt blood clotting. Venomous animals cause tens of thousa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megarachne Servinei
''Megarachne'' is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of ''Megarachne'' have been discovered in deposits of Late Carboniferous age, from the Gzhelian stage, in San Luis, Argentina. The fossils of the single and type species ''M. servinei'' have been recovered from deposits that had once been a freshwater environment. The generic name, composed of the Ancient Greek μέγας (''megas'') meaning "great" and Ancient Greek ἀράχνη (''arachne'') meaning "spider", translates to "great spider", because the fossil was misidentified as a large prehistoric spider. With a body length of , ''Megarachne'' was a medium-sized eurypterid. If the original identification as a spider had been correct, ''Megarachne'' would have been the largest known spider to have ever lived. Eurypterids such as ''Megarachne'' are often called "sea scorpions", but the strata in which ''Megarachne'' has been found indicates that it dwelled in freshwater and not in marine envi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphodros Rufines
''Sphodros'' is a genus of North American purseweb spiders first described by Charles Athanase Walckenaer in 1835. It was considered a synonym of '' Atypus'' until 1980. Species it contains seven species in the United States, Canada, and Mexico: *'' Sphodros abboti'' Walckenaer, 1835 ( type) – Southern Georgia, Northern Florida *'' Sphodros atlanticus'' Gertsch & Platnick, 1980 – Eastern and Central United States *'' Sphodros coylei'' Gertsch & Platnick, 1980 – South Carolina, Virginia *'' Sphodros fitchi'' Gertsch & Platnick, 1980 – Nebraska, Kansas, Oklahoma, Arkansas, Iowa *'' Sphodros niger'' ( Hentz, 1842) – Canada, Northeastern United States (south to Tennessee and east to Kansas) *'' Sphodros paisano'' Gertsch & Platnick, 1980 – Southeastern Texas, Mexico *''Sphodros rufipes ''Sphodros rufipes'', sometimes called the red legged purseweb spider, is a Mygalomorphae, mygalomorph spider from the southern United States, though it has been photographed as fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheliceral Fang
The chelicerae () are the mouthparts of the subphylum Chelicerata, an arthropod group that includes arachnids, horseshoe crabs, and sea spiders. Commonly referred to as "jaws", chelicerae may be shaped as either articulated fangs, or similarly to pincers. Some chelicerae, such as those found on nearly all spiders, are hollow and contain (or are connected to) venom glands, and are used to inject venom into prey or a perceived threat. In ''Pisaurina mira'', also known as the nursery web spider, the chelicerae are utilized to snatch the prey once it becomes within reach, facilitating the "sit-and-wait ambush predator" behavior. Both pseudoscorpions and harvestmen have structures on their chelicerae that are used for grooming (papillae in pseudoscorpions, cheliceral teeth in Opiliones). Types Chelicerae can be divided into three kinds: jackknife chelicerae, scissor chelicerae, and 3-segmented chelate chelicerae. Jackknife chelicerae The jackknife chelicera is subchelate (with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic period (), and the Classical period (). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article primarily contains information about the Epic and Classical periods of the language. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regarded as a separate historical stage, although its earliest form closely resembles Attic Greek and its latest form approaches Medieval Greek. There were several regional dialects of Ancient Greek, of which Attic Greek developed into Koine. Dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endoparasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparasite lives inside the host's body; an ect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acroceridae
The Acroceridae are a small family (biology), family of odd-looking flies. They have a hump-backed appearance with a strikingly small head, generally with a long proboscis for accessing nectar. They are rare and not widely known. The most frequently applied common names are small-headed flies or hunch-back flies. Many are bee or wasp mimicry, mimics. Because they are parasitoids of spiders, they also are sometimes known as spider flies. Description The Acroceridae vary in size from small to fairly large, about the size of large bees, with a wingspan over 25 mm in some species. As a rule, both sexes have tiny heads and a characteristic hump-backed appearance because of the large, rounded thorax. In appearance, they are compact flies without major bristles, but many species have a bee-like hairiness on their bodies, and some are bee or wasp mimicry, mimics. In most species, the eyes are holoptic in both sexes, the heads seemingly composed mainly of the large ommatidia, facete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araneomorphae
The Araneomorphae (also called the Labidognatha) are an infraorder of spiders. They are distinguishable by chelicerae (fangs) that point diagonally forward and cross in a pinching action, in contrast to the Mygalomorphae (tarantulas and their close kin), where they point straight down. Araneomorphs comprise the vast majority of living spiders. Distinguishing characteristics Most spider species are Araneomorphae, which have fangs that face towards each other, increasing the orientations they can employ during prey capture. They have fewer book lungs (when present), and the females typically live one year. The Mygalomorphae have fangs that face towards the ground, and which are parallel to the long axis of the spider's body, thus they have only one orientation they can employ during prey capture. They have four pairs of book lungs, and the females often live many years. Image:Atrax robustus.jpg, This ''Atrax robustus'' shows the orientation of Myglamorphae fangs. Image:Che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theraphosa Blondi
The Goliath birdeater (''Theraphosa blondi'') belongs to the tarantula family Theraphosidae. Found in northern South America, it is the largest spider in the world by mass () and body length (up to ), and second to the giant huntsman spider by leg span. It is also called the Goliath tarantula or Goliath bird-eating spider; the practice of calling theraphosids "bird-eating" derives from an early 18th-century copper engraving by Maria Sibylla Merian that shows one eating a hummingbird. Despite the spider's name, it rarely preys on birds. Physical description These spiders can have a leg span up to , a body length of up to and can weigh up to .Goliath Bird-Eating Spider , Arkive Birdeaters are one of the few tarantula species that lack tibial spurs, located on the first pair of legs of mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
