What are "predatory fungi" and what is unique about the largest known specimen?

What are "predatory fungi"?

Predatory fungi are a type of fungus that has structures adapted to capture small worms living in the soil. They are also known as trapping fungi.

The Largest Known Specimen:

The largest known specimen of a predatory fungus is a honey fungus (Armillaria ostoyae), also called the dark honey fungus. It was discovered in the Malheur National Forest in Oregon, USA. Its mycelium covers an area of 9 square kilometers, which is equivalent to about 1200 football fields. The age of this colossal fungus is estimated to be 2400 years.