This species belongs to a larger grouping, the Asian-American moon moths. Like the trees on which they feed, these American and Asian insects look very similar (here are a couple of examples of look-alikes, and then some more crazy-winged cousins). They have a distribution that encompasses the east of North America and parts of Asia, reflecting the old biogeographic continuity of these places.
Unfortunately, parasitic flies introduced to North America to control gypsy moths are turning their attentions to the luna moth. So far, lunas appear to be more robust than most other large moth species, many of which are in decline or have gone regionally extinct, at least in New England. We lack long-term data (to my knowledge) on populations of moths in the south.
Why such long tails? Bat befuddlement. Ed Yong tells this luna-tale, with a review of some cool experiments, along with videos, on his fabulous blog at National Geographic.
Closing moth thoughts as they antennate the air’s breath, seeking pheromonal scent (attributed to Rumi from, as far as I can tell, Coleman Barks’ interpretations of English translations):
“At night, I open the window and ask the moon to come and press its face against mine. Breathe into me. Close the language-door and open the love-window. The moon won’t use the door, only the window.”