Vampiric Glider

The second-favorite survival horror story about Kargaan Vale involves discovering a cute little tree critter with deceptively moist round eyes, only to have it sink its paralyzing fangs into the traveler's flesh and drink his blood. This is a very real thing that happens. Although blood loss is often negligible, it's a vector for infection and the paralysis renders the traveler vulnerable to other predators, of which there are many.