The multicolored Asian lady beetle, Harmonia axyridis (Pallas), native to Asia, has recently been detected in South America after successfully invading North America and Europe. This coccinellid is a voracious predator; therefore, it is popular and effective in biological control. Unfortunately, H. axyridis also has associated adverse impacts (i.e., as a household pest, pest of fruit production, and threat to non-target organisms). To predict the potential geographic extent of impacts of H. axyridis in South America we review the history of its invasion in the Western Hemisphere and address various factors critical to the future invasion (i.e., arrival, establishment, and spread) of new areas of South America. The likelihood of continued introductions (i.e., arrival) of H. axyridis to South America seems high, due to its popularity as a biological control agent and through accidental introductions. Establishment also seems likely in broad regions of South America. Climate matching with the native range suggested that much of southern South America may be suitable for establishment. In contrast, habitat matching with the native range suggested that northern South America may be more suitable. In addition, prey availability should not limit establishment of this predator. Once established, H. axyridis seems likely to spread by flight and human-assisted means. Overall, the invasion of H. axyridis over broad areas in South America seems likely.
