Do ladybugs eat ants

No, different ladybugs eat different kinds of aphids. That's why the Asian or Japanese ladybug [Harmonia axyridis] was brought into the United States of America. The native ladybugs [Coccinelidae family] couldn't be counted on to eat pecan tree aphids. But researchers discovered that the Asian variety were voracious eaters of pecan tree aphids in their native lands.