Day 285#: Blunt-Headed Tree Snake
Today's animal of the day is the Blunt-Headed Tree Snake (Imantodes cenchoa)!
Photo credit: Geoff Gallice
Also known as the fiddle-string snake, this species of arboreal snake can be found in the tropical rainforests of Mexico as well as both Central and South America. They can reach a maximum size of 4 ft 11 in long and are known for their long, slender bodies with comically large heads. Their eyes are also incredibly large compared to the rest of their bodies, and take up nearly 26% of their total head space. While this might look really goofy, it actually helps improve their vision significantly compared to other species of snakes, which are known for having very poor eyesight. Most other snakes rely mostly on their sense of smell as well as vibrations to detect predators and prey, but since the blunt-headed tree snake needs to be able to clearly see the branches of the trees it's climbing, they need to have better vision than the average snake. The slitted shape of its pupil even allows it to look down without moving its entire head, which most snakes are unable to do.
Photo credit: Max Hofmann
Blund-headed tree snakes are active mostly at night, which is another reason they need good eyesight, and will forage through the vegetation in search of prey. Their diet consists mostly of lizards, but they'll also often go after frogs and have been known to eat eggs when the opportunity presents itself. Females tend to be larger than males, meaning that they can take on larger prey. Size isn't the only difference between the sexes. In fact, the populations in the north and south actually seem to exhibit two very different types of sexual dimorphism. Northern males tend to have longer tails than southern males and both types of females, while southern females tend to have much larger heads.
Photo credit: Laurent Hesemans
These snakes are members of the Colubrid family, which also includes hognoses, garters, kingsnakes, and many other species of snakes. Like many of its cousins, the blunt-headed tree snake is technically venomous, but they are rear-fanged venomous instead of front-fanged. This is a useful adaptation when a good portion of your diet consists of frogs and toads, but it isn't really well-suited for injecting venom into humans, since it would require letting the snake chew on you for a good while before it could envenomate you. Luckily, even if you did let one chew on you, their venom is pretty mild, and they're not considered dangerous to humans.
