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''Cyrtophora exanthematica'' are tent spiders common in tropical Asia and Australia. They are commonly known as double-tailed tent spiders because of the pair of blunt projections at the end of their abdomens. They are harmless to humans. Double-tailed tent spiders build large nonsticky webs of two parts – a tangle web and a finely-meshed horizontal orb web. The females of the species are larger than the males and they may vary considerably in colour. They are easily distinguishable by their shape, the markings on their backs, and the way the females have the habit of guarding their eggs by splaying their bodies over them. ==Description== Their common name 'double-tailed tent spider' comes from the pair of blunt projections at the posterior end of their abdomens.〔 They are also known under other common names in Australia, including dome spider, bowl spider, pan-web spider, and scoop-web spider.〔(【引用サイトリンク】title=Tent spiders: ''Cyrtophora moluccensis'', ''Cyrtophora hirta'', ''Cyrtophora exanthematica'', family Araneidae )〕〔 Like other members of the genus ''Cyrtophora'', the upper side of the cephalothorax of double-tailed tent spiders are flattened. The cephalothorax, the sides of the abdomen, and the legs are covered with white hairs. Its leg formula is I,II,III,IV – that is, the longest legs are the first pair at the front, the second pair the next longest, the third pair shorter than the second, and the last pair the shortest. The eight eyes are more or less of equal size and arranged in two recurved rows.〔 They also possess the characteristic pair of humps on the front side of their abdomen, somewhat resembling 'shoulders' and giving them the distinctive triangular shape. On the upper side are eight prominent sigilla (small pit-like depressions) arranged in two rows. The abdomen is subrectangular, with somewhat flat sides, and has small tubercules at the front. It is longer than it is wide and tapers down towards the rear. The bottom side of the abdomen is usually brown with yellow book lungs. The spinnerets are rimmed with white. The epigynum in females possesses a short triangular scape (or ovipositor). The sperm receptacles (spermathecae) are globular.〔 They can vary considerably in colour.〔(【引用サイトリンク】title=''Cyrtophora exanthematica'' (Double Tailed Tent Spider) )〕 They can be red, pink, orange, yellow, brown, grey, pale brown, or completely black. In some individuals two somewhat wavy and sometimes 'beaded' chalk-white line patterns are clearly visible, running from the front of the abdomen, to the tip of the 'humps', and down to below its pair of 'tails'. In others, they are only present as faint lines. Double-tailed tent spiders are sexually dimorphic, with the males generally far smaller than the females.〔 Female adults average around in length (excluding the legs), but can reach up to .〔 Male adults average only , with the abdomen about the same size as the cephalothorax and with prominent pedipalps.〔〔 Double-tailed tent spiders closely resemble ''Cyrtophora parangexanthematica'' in the Philippines. A fact reflected by its scientific name which literally means "like exanthematica" in Filipino.〔 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「Cyrtophora exanthematica」の詳細全文を読む スポンサード リンク
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