The Mystery of the Yellow Ladybug One afternoon, while watering my plants, a bright yellow ladybug landed on my arm. I was surprised—was it rare or even a ladybug at all? After some research, I learned that yellow ladybugs are real and just one of over 5,000 species. While red ladybugs feast on aphids, many yellow ones, like those in the Psyllobora family, prefer fungi like mildew. So, if you spot a yellow ladybug, consider it a lucky charm—and a tiny garden helper