I miss the bug-eyed freaks. I was expecting them at some point. But I guess - never to be seen again?

Geckos thus far are confined to the West Coast. The East Coasters get to deal with Mirelurks.

Well, the Deathclaw is a mutated Gecko, if that helps any.

Where are the ants!? Ants are everywhere.. but not in Boston?

Yeah I was wondering that I know that in FO3 the fire ants were made fire breathing by a mad scientist. They could quite easily have spread to Boston from Washington DC in those 10 years since then.