Honestly, her estimates are pretty low. A liter of water may hold as many as 40K different species, easily. Most of them different from those in a few grams of soil 200 meters away.

Some students at my school found an entirely new type of bacteriophage from a random soil sample this semester. And when I say entirely new- it really is. It represents a family that has been never been discovered before.

And this sort of discovery isn’t uncommon