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Adalia bipunctata, commonly known as the two-spot ladybird, two-spotted ladybug or two-spotted lady beetle, is a carnivorous[1] beetle of the family Coccinellidae that is found throughout the holarctic region. It is very common in western and central Europe and North America. It is used as a biological control agent.
Taxonomy The two-spotted ladybird was one of the many species originally described by Linnaeus in his 18th century work, Systema Naturae, its original name was Coccinella bipunctata.[2] Its specific name from the Latin bi- "two", and punctata "spotted".[3] Phenotypic variations The most familiar form of the two-spot ladybird beetle is the red one with the two black spots. However, there also exists a black form with red spots on it. In addition, there are intermediate forms, but they occur only rarely in nature.[4] Prey Two-spotted lady beetles feed on aphids and other small insects.[1][4][5] Life cycle  Life cycle Sex ratio anomalies  Spotted lady beetles mating Symbiosis In some populations, the majority of the beetles are female. In these populations, 80-90% of the offspring of a female are female. The cause of this anomaly is the presence of symbiotic bacteria living within the gametic cells of the female lady beetles. The bacterium is too large to live in the male gametes (sperm), so the bacterium can be transmitted to the next generation only through female gametes. When it ends up in a male, it will die when the male dies. Therefore, it kills most of the male embryos in the newly laid eggs. These dead embryos then serve as food for their sisters when they emerge from their eggs. This trait is associated with a variety of different bacteria (Wolbachia,[6] Rickettsia,[7] Spiroplasma[8]), which are present in between 0 and 20% of females, depending on locality. Parasitism The two spot ladybird also carries a sexually transmitted infection in Central and Eastern Europe. The infection is an ectoparasitic mite Coccipolipus hippodamiae that transfers between male and female (and female and male) during copulation.[9] The infection sterilizes female two spot ladybirds, and at some points of the year, up to 90% of adult 2-spots become infected.[10] As biological control agent A. bipunctata is used as a localised biological control agent against aphids in, for example, greenhouses.. The Two-spotted lady beetle was introduced into Australia specifically as a biological control agent.[11] References cs:Slun ko dvojte n de:Zweipunkt-Marienk fer es:Adalia bipunctata fr:Coccinelle deux points ga:B n D dh bhallach lv:Divpunktu m r te lt:Dvita k adalija hu:K tpettyes katicabog r nl:Tweestippelig lieveheersbeestje no:Toprikket marih ne nn:Toprikka marih ne pl:Biedronka dwukropka ru: sk:Lienka dvojbodkov sv:Tv prickig nyckelpiga
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