Jaculus
Region of origin: Medieval Europe
A creature from medieval bestiaries, the jaculus or javelin snake was a small, flying serpent which did not possess venom so would instead perch in trees and wait for its intended victim to pass underneath, at which point it would launch itself rigidly and strike the prey, knocking it out or fatally wounding it through impact.
Originally posted on Tumblr on July 30, 2016
The Compendium of Arcane Beasts and Critters 