The mothman decription corresponds closely to what is called a rakshasha in the Vedic literature of India. A raskasha is some kind of winged demon who is carnivorous. This just means that these types of beings have been encountered before.
They live underground, of course.
What we've heard is that on the surface, human growth is stunted,
longevity
is curtailed, etc., and that in cavern worlds and in the hollow portion,
growth is tremendous and longevity is, well, long. What would an insect be
like in the depths of the planet? As large as a human?
The movie The Mothman Profecies based on reported appearances of the mothman in West Virginia. The mothman answeres to the description of the Vedic rakshasha. (keep away from them when they are hungry)