Hornworms are caterpillars that turn into a moth after pupation.
There are two similar species: the tobacco hornworm (with a red horn) and the tomato hornworm (with a black horn). Wild hornworms are pests, but a lot of hornworms are produced in captivity as pet food for various insectivores.
While researching this article I have found several recipes how to cook hornworms for human consumption — the curious thing about them was that they weren’t food consumed in some exotic location, but North American ‘western’ food items made out of caterpillars.
Tobacco Hornworm (Manduca sexta) – Encyclopedia of Life.
The Worm Lady Hornworms.
Manduca sexta on Wikipedia.
Manduca quinquemaculata on Wikipedia.
Fried Green Tomato Hornworms on The Daily Meal.