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The spider species ''Argiope aurantia'' is commonly known as the yellow garden spider,〔(Pictures of yellow garden spider ''A. aurantia'' ) (free for noncommercial use)〕〔Weber, Larry (2003). ''Spiders of the North Woods''. Duluth, MN: Kollath-Stensons. pp.76-77.〕 black and yellow garden spider,〔(Black and Yellow Garden Spider - ''Argiope aurantia'' ) Creative Commons Licensed〕 golden garden spider,〔Eaton, E.R. & K. Kaufman (2007). Kaufman Field Guide to Insects of North America.'' New York:Houghton Mifflin. p.22.〕 writing spider, corn spider, or McKinley spider It is common to the contiguous United States, Hawaii, southern Canada, Mexico, and Central America. They have distinctive yellow and black markings on their abdomens and a mostly white cephalothorax. Its scientific Latin name translates to "gilded silver-face" (the genus name ''Argiope'' meaning "silver-face", while the specific epithet ''aurantia'' means "gilded"). Males range from females from . These spiders may bite if disturbed or harassed, but the venom is seemingly harmless to humans. ==Habitat== Garden spiders often build webs in areas adjacent to open sunny fields where they stay concealed and protected from the wind. The spider can also be found along the eaves of houses and outbuildings or in any tall vegetation where they can securely stretch a web. Female ''Argiope aurantia'' spiders tend to be somewhat local, often staying in one place throughout much of their lifetime. The web of the yellow garden spider is distinctive: a circular shape up to 2 feet (60 cm) in diameter, with a dense zigzag of silk, known as a stabilimentum, in the center. The purpose of the stabilimentum is disputed. It is possible that it acts as camouflage for the spider lurking in the web's center, but it may also attract insect prey, or even warn birds of the presence of the otherwise difficult-to-see web. Only those spiders that are active during the day construct stabilimenta in their webs. To construct the web, several radial lines are stretched among four or five anchor points that can be more than three feet apart. The radial lines meet at a central point. The spider makes a frame with several more radial lines and then fills the center with a spiral of silk, leaving a 5/16 to 3/8 inches (8 to 9.5 mm) gap between the spiral rings, starting with the innermost ring and moving outward in a clockwise motion. To ensure that the web is taut, the spider bends the radial lines slightly together while applying the silk spiral. The female's web is substantially larger than the male's, who builds a small zigzag web nearby. The spider occupies the center of the web, usually hanging head-down, waiting for prey to become ensnared in the web. If disturbed by a possible predator, she may drop from the web and hide on the ground nearby. The web normally remains in one location for the entire summer, but spiders can change locations usually early in the season, perhaps to find better protection or better hunting. The garden spider can oscillate her web vigorously while she remains firmly attached in the center.〔(Garden Spider Oscillating Web - Video )〕 This action might prevent predators like wasps and birds from drawing a good bead, and also to fully entangle an insect before it cuts itself loose. However, in a case observed in Georgia, Davis witnessed a ''Vespa crabro'' fly into the spider’s web and get tangled up. Upon looking closer it was found that ''V. crabro'' was actually cutting free prey that had been caught in the ''A. aurantia'' web. In this case, ''A. aurantia'' did not interfere or fight with the European Hornet probably because it dropped down and hid nearby. In a nightly ritual, the spider consumes the circular interior part of the web and then rebuilds it each morning with fresh new silk. The radial framework and anchoring lines are not usually replaced when the spider rebuilds the web. The spider may be recycling the chemicals used in web building. Additionally, the fine threads that she consumes appear to have tiny particles of what may be minuscule insects and organic matter that may contain nutrition. The garden spider does not live in very dense location clusters like other orb spiders such as the golden orb web spider. The garden spider keeps a clean orderly web in comparison to the cluttered series of webs built and abandoned by groups of golden orb spiders. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Argiope aurantia」の詳細全文を読む スポンサード リンク
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