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Multicolored Asian Lady Beetle (Harmonia axyridis)
The multicolored Asian lady beetle was introduced to North America for biological aphid control and is an effective predator in gardens and agricultural settings, but it has become a significant nuisance pest as it invades homes in autumn in enormous numbers to overwinter in wall voids and attics. Unlike native lady beetles, it can bite and releases a foul-smelling yellowish fluid when disturbed that can stain surfaces and trigger allergic reactions. Sealing all structural entry points before fall and applying exterior perimeter treatments provides the best protection against indoor invasions.