Deathclaw

Deathclaws are a race of evolved reptilians, in the [Fallout] universe. It is rumored in Fallout 1 that Deathclaws are intelligent and in Fallout 2, you can find (and talk to) a Deathclaw which has had it's intelligence enhanced to the level where it is capable of deception. In Fallout: Tactics you can help a Deathclaw matriarch and thereby gain Deathclaw members for your squad. At least in Fallout: Tactics, Deathclaws are all intelligent.

In all three games, there are rural deathclaws. They may be intelligent, but confirming that is rather hard, as they are at least smart enough to see you as their next meal.