The eyelash pit viper (Bothriechis schlegelii) is one of the iconic reptiles of Costa Rica. Here are two young morphs, the first a classic mossy speckled green from the Osa Peninsula, and the second a pale color with pastel undertones from Cahuita National Park. These snakes generally have an extremely calm demeanor, though the pale morph was in shed and excessively flicked its tongue as a warning. Eyelash vipers are arboreal ambush hunters, settling in the same spot for days or weeks awaiting small prey that may wander by. Like many vipers they use their tails as a caudal lure, undulating the tip in a worm-like manner to entice prey to investigate and come closer. Their tails are also prehensile, and in the photos below you can see the viper gripping a branch with its tail, much like a spider monkey would do when maneuvering around in the forest canopy.