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''Harmonia axyridis'' is a large coccinellid beetle. Its colour ranges from yellow-orange to black, and the number of spots between none and 22. It is native to eastern Asia, but has been artificially introduced to North America and Europe to control aphids and scale insects. It is now common, well known, and spreading in those regions, and has also established in South Africa and widely across South America. It is commonly known as the harlequin ladybird (because it occurs in numerous colour forms). It is also known in North America as the Ladybug, and (because it invades homes in October in preparation for overwintering) as Halloween lady beetle.〔(【引用サイトリンク】title=The Harlequin Ladybird Survey )〕 In Japan, it is not generally distinguished from the seven-spot ladybird which is also common there. When the species first arrived in the UK, it was labelled in jest as "the many-named ladybird", because among the names listed were: multivariate, southern, Japanese, and pumpkin ladybird.〔Ladybird Survey page "''Harmonia axyridis'' (Pallas) in Britain" () Accessed 7 Jan 2008〕 ==Description== ''Harmonia axyridis'' is a "typical" coccinellid beetle in shape and structure, being domed and having a "smooth" transition between its elytra (wing coverings), pronotum, and head. It occurs in three main color forms: red or orange with black spots (known as form ''succinea''); black with four red spots (form ''spectabilis''); and black with two red spots (form ''conspicua''). However, numerous other forms have also been recorded, particularly in the native range. The beetle is typically large for a coccinellid (5.5–8.5 mm long) and even more dome-shaped than native European species. These characteristics distinguish ''H. axyridis'' from native species in the UK. A useful informal clue for distinguishing this species from most other Coccinellidae is that the pronotum of the succinea colour forms of ''Harmonia axyridis'' has white markings that typically define an "M"-shaped black area, as seen on a beetle resting head-upwards (or "W"-shaped if it is head-down).〔http://www.harlequin-survey.org/recognition_and_distinction.htm Harlequin Ladybird Survey - Recognition and Distinction〕〔http://bugguide.net/node/view/397 Bugguide〕 This is most obvious in the common 19 spot form, less obvious in some of the less common varieties,〔http://www.biocontrol.entomology.cornell.edu/predators/Harmonia.html Cornell University〕 but works well a rule of thumb. They always have reddish-brown legs and are obviously brown on the underside of the abdomen, even in the melanic colour forms.〔 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「Harmonia axyridis」の詳細全文を読む スポンサード リンク
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