At first glance, there's almost no denying that you're looking at a snake, but upon closer inspection, you'll see that it's actually a caterpillar, called the Hemeroplanes triptolemus. They're basically moths of the Sphingidae family - found in many parts of South America, Africa and Central America - that are capable of expanding their anterior body segments to closely resemble a snake, complete with reptilian scales and scary eyes, when in larval form. Continue reading for a video and more information.
Here's what we found on the website of Tracie "the bug lady", who runs a nighttime adventure trek in the rainforests of Drake Bay, Costa Rica: "At first glance, this large caterpillar was quite ordinary. As Tracie lowered the branch, we realized that the caterpillar was changing...becoming something entirely different. After posing placidly for a few shots, the caterpillar suddenly released the twig on which it was perched and hung dangling by its rear set of legs. It began to pull the tip of its head inward, puffing out the front part of its body."