Anguisette

Anguisettes (Ophis Volantes) are a magical species of serpent.

Description
Anguisettes (whose name is drawn from the Latin word for an adder and the -ette syllable to denote small size) are small snakes that can swim through the air as if it were water. Anguisettes, while effective spies for Parselmouths, are devoid of venom, and rely solely on their ability to flee through the air.

Potions
Shredded Anguisette skin is a component in the Invisibility Potion.

British Ministry of Magic Classification
Anguisettes, like all snakes, are classified as Beasts. Because of their lack of venom, they are given the X threat level.

Canon

 * Anguisettes do not exist in Harry Potter canon.