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Tube-dwelling Spider
Tube-dwelling spiders (Segestriidae) are a family of araneomorph spiders first described by Eugène Simon in 1893. It consists of five genera, two large and widespread, '' Segestria'' and ''Ariadna'', and three smaller genera, '' Citharoceps'', '' Gippsicola'' and '' Indoseges''. They are haplogyne spiders, related to the Dysderidae and placed in clade or superfamily Dysderoidea. Members of this family are easily recognized because their first three pairs of legs are arranged forward instead of two and they have six eyes instead of eight, arranged in a semicircle. The leg structure appears to be an adaptation for living in silken tubes. Unlike those of the atypical tarantulas, these tubes may branch and are often built in tree bark fissures, as well as under stones. Both ''Segestria'' and ''Ariadna'' live in North America, South America, Eurasia, Africa and New Zealand, though ''Ariadna'' also lives in Australia. Genera , the World Spider Catalog accepts the following ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Segestria Florentina
''Segestria florentina'' is the biggest European segestriid spider. Some vernacular names are green-fanged tube web spider and cellar spider, although the latter is not exclusive to this species. Description Females can reach a body length of 22 mm, males up to 15 mm. This species is much darker than others of the same genus. While subadult spiders have a greyish opisthosoma with a marking similar to '' Segestria senoculata'', adults are of a uniform black, sometimes with a green iridescent shine, especially on the chelicerae,Bellmann, H. (1997). Kosmos-Atlas Spinnentiere Europas. ''Kosmos''. which reflect with a striking green. The sexes are similar. Adults occur from June to November. Habits They spin a tubular web, often in cracks of buildings. Six or more silken lines radiate from it, and the spider waits in the entrance, touching the lines with the frontal six legs. Prey triggering these lines get caught, and the spider immediately retreats again to eat it. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysderidae
Dysderidae, also known as woodlouse hunters, sowbug-eating spiders, and cell spiders, is a family of araneomorph spiders first described by Carl Ludwig Koch in 1837. They are found primarily in Eurasia, extending into North Africa with very few species occurring in South America. ''Dysdera crocata'' is introduced into many regions of the world. Dysderids have six eyes, and are haplogyne, i.e. the females lack a sclerotized epigyne. There is a substantial number of genera, but two of them, ''Dysdera'' and ''Harpactea'', account for a very large number of the species and are widespread across the family's range. One species, ''Dysdera crocata'' (the woodlouse hunter), has been transported over much of the planet together with its preferred foods—woodlice. ''Dysdera'' also feeds on beetles. These spiders have very large chelicerae, which they use to pierce the armored bodies of woodlice and beetles. There are also some reports that they have a mildly toxic venom that can cause lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Spider Catalog
The World Spider Catalog (WSC) is an online searchable database concerned with spider taxonomy. It aims to list all accepted families, genera and species, as well as provide access to the related taxonomic literature. The WSC began as a series of individual web pages in 2000, created by Norman I. Platnick of the American Museum of Natural History. After Platnick's retirement in 2014, the Natural History Museum of Bern (Switzerland) took over the catalog, converting it to a relational database A relational database is a (most commonly digital) database based on the relational model of data, as proposed by E. F. Codd in 1970. A system used to maintain relational databases is a relational database management system (RDBMS). Many relati .... , 50,151 accepted species were listed. The order Araneae (spiders) has the seventh-most species of all orders. The existence of the World Spider Catalog makes spiders the largest taxon with an online listing that is updated regularly. It ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With billion people as of , it accounts for about of the world's human population. Africa's population is the youngest amongst all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Despite a wide range of natural resources, Africa is the least wealthy continent per capita and second-least wealthy by total wealth, behind Oceania. Scholars have attributed this to different factors including geography, climate, tribalism, colonialism, the Cold War, neocolonialism, lack of democracy, and corruption. Despite this low concentration of wealth, recent economic expansion and the large and young population make Afric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago and the Russian Far East to the east. The continental landmass is bordered by the Atlantic Ocean and Africa to the west, the Pacific Ocean to the east, the Arctic Ocean to the north, and by Africa, the Mediterranean Sea, and the Indian Ocean to the south. The division between Europe and Asia as two continents is a historical social construct, as many of their borders are over land; thus, in some parts of the world, Eurasia is recognized as the largest of the six, five, or four continents on Earth. In geology, Eurasia is often considered as a single rigid megablock. However, the rigidity of Eurasia is debated based on paleomagnetic data. Eurasia covers around , or around 36.2% of the Earth's total land area. It is also home to the lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern subregion of a single continent called America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. The continent generally includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one internal territory: French Guiana. In addition, the ABC islands of the Kingdom of the Netherlands, Ascension Island (dependency of Saint Helena, Ascension and Tristan da Cunha, a British Overseas Territory), Bouvet Island ( dependency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the west and south by the Pacific Ocean. Because it is on the North American Plate, North American Tectonic Plate, Greenland is included as a part of North America geographically. North America covers an area of about , about 16.5% of Earth's land area and about 4.8% of its total surface. North America is the third-largest continent by area, following Asia and Africa, and the list of continents and continental subregions by population, fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 579 million people in List of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's population. In Americas (terminology)#Human ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are some three trillion mature trees in the world. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atypical Tarantula
Atypidae, also known as atypical tarantulas or purseweb spiders, is a spider family containing only three genera. They are accomplished ambush predators that spend most of their time in a sock-like, silken retreat on the ground from where they kill their prey. Distribution '' Sphodros'' and '' Atypus'' occur in North America, while '' Atypus'' and '' Calommata'' occur in Asia and Africa. Only '' Atypus'' species are found in Europe. '' Atypus affinis'', '' Atypus muralis'', and '' Atypus piceus'' are the only mygalomorph spiders found in northwestern Europe. Biology ''Atypus'' builds a silken tube parallel to the surface of the ground. While up to 8 cm of the tube lie on the ground, about 20 cm are buried vertically. The spider rests at the bottom of the tube. When prey walks on the exposed part, the spider, alerted by the vibrations, stabs the prey through the silk, cuts the web and drags the prey inside to be eaten. ''Calommata'' species, instead of building a purse w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysderoidea
The Dysderoidea are a clade or superfamily of araneomorph spiders. The monophyly of the group, initially consisting of the four families Dysderidae, Oonopidae, Orsolobidae and Segestriidae, has consistently been recovered in phylogenetic studies. In 2014, a new family, Trogloraptoridae, was created for a recently discovered species ''Trogloraptor marchingtoni''. It was suggested that Trogloraptoridae may be the most basal member of the Dysderoidea clade. However, a later study found that Trogloraptoridae was placed outside the Dysderoidea and concluded that it was not part of this clade. Phylogeny Dysderoidea are members of the Haplogynae clade: spiders with simpler copulatory organs (palpal bulbs and epigynes) than other araneomorphs. One hypothesis for relationships within the Haplogynae is shown below. The status of the Trogloraptoridae is unclear. The family was not included in one study which otherwise found the same topography, but it was placed outside even the Filista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogyne
The Haplogynae or haplogynes are one of the two main groups into which araneomorph spiders have traditionally been divided, the other being the Entelegynae. Morphological phylogenetic studies suggested that the Haplogynae formed a clade; more recent molecular phylogenetic studies refute this, although many of the ecribellate haplogynes do appear to form a clade, Synspermiata. Unlike the Entelegynae, haplogynes lack hardened (sclerotized) female genitalia (epigynes). Most of the species within this group have six eyes, as opposed to most other spiders. Spiders in the genus '' Tetrablemma'' (Tetrablemmidae) have only four eyes, as do some members of the family Caponiidae; caponiids may even have only two eyes. However, spiders in the family Plectreuridae have the normal eight eyes. Phylogeny The Haplogynae are one of the two major groups into which araneomorph spiders were traditionally divided, the other being the Entelegynae. In 2005, Coddington summarized the relationships ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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