Head of Viper
All vipers have a distinctive triangular head. This head shape is due to the placement of their large venom glands in the mouth. Some nonvenomous species have evolved a similarly shaped head in order to potentially trick predators into thinking they are vipers. Additionally, most vipers have keeled scales on their head. The pupils are vertically elliptical seen on the side of the head, just behind the nostrils. The coloring and patterns can varies species to species that serve as camouflage. Pit vipers has a pit organ (which contain a membrane that can detect infrared radiation from warm bodies up to one meter away) in between the eye and the nostrils.
About the animal
Most are heavy-bodied ambush predators. All are venomous, some highly venomous, viper venom serves two purposes. It helps the snake kill its prey. It also aids digestion by breaking down tissue. Vipers have a pair of prominent fangs located in the front of the mouth. These fangs are used to inject venom into prey. These snakes have hinged fangs that can be folded back when not in use. Some have heat-sensing pits that are used to hunt prey. Most vipers have a triangular or wedge-shaped head, resulting from large venom glands located behind the eye area. Vipers typically have a short and stocky body, when compared to the more slender cobras and mambas. They use their thick bodies as a “springboard” from which they deliver quick and powerful strikes. Most vipers have excellent camouflage that helps them blend in with their natural surroundings. Most vipers are viviparous, which means they give birth to live young. Only a few species within this family lay eggs (the bushmaster is an example of an egg-laying viper). Vipers exist in a wide range of habitats, including mountains, deserts and jungles, and distributed widespread, and occur all over the world, except in Australia and Antarctica. They can survive farther north and south of the equator than most snake species.