What is a key characteristic of subterranean termites?

Subterranean termites are unique among termite species primarily because they require soil contact for moisture, making them dependent on a moist environment to thrive. This characteristic is crucial for their survival, as it helps them maintain the necessary hydration levels needed for their physical processes and for the digestion of cellulose.

These termites construct their colonies underground and often create mud tubes, which allow them to travel between their nest in the soil and their food sources, typically wood. By doing so, they can protect themselves from the surrounding environment while ensuring they have access to the moisture they need.

The other aspects mentioned—such as living without moisture or building large visible mounds—do not apply to subterranean termites. Instead, their need for direct soil contact underlines their ecological role, where they can efficiently break down organic matter and contribute to the soil ecosystem. This dependence on soil moisture exemplifies how subterranean termites have adapted to their environment to ensure their survival and reproductive success.