Candidatus

Okay kiddo, imagine there are these teeny tiny living things called bacteria. They're so small you can't even see them with just your eyes! Well, sometimes these bacteria can get together with other bacteria and form a community. But sometimes they don't get along so well and one of them might decide to live inside another one.

Now, when one bacteria lives inside another bacteria, it's called symbiosis. But sometimes the one living inside is so small, scientists can't actually see it! That's where Candidatus comes in. It's like a special nickname for these ultra-tiny bacteria that we know are living inside other bacteria, but we can't identify them individually.

Does that make sense, kiddo?