Snaptrapper

"Its the Venus Flytrap of dragons, the devious Snaptrapper!"

- (Book of Dragons) Gobber introducing the Snaptrapper The Snaptrapper is a four-headed dragon Mystery Class dragon. There is also a known rare breed called the Leafy Snaptrapper.

Snaptrapper
With triple-split jaws on each of this Mystery Class Dragon’s 4 heads, it looks like a man-eating Venus Flytrap. Just not as friendly.

Leafy Snaptrapper
Most active during its Fall hunting season. If you are lucky enough to see one, you'll be impressed. If you are unlucky, you'll end up as lunch."

Snaptrapper
The Snaptrapper is a dragon that has four heads, each with three jaws. Their tails are forked like the Hideous Zippleback's, and they look somewhat like the latter as well. Their unique, frightening jaws open up in a way that resembles a flower blooming, and the spines on their neck, body and tail look similar to leaves. All four heads of the Snaptrapper have three tongues; these tongues each resemble the anther of a flower, as it is the Snaptrapper's tactic to resemble a plant of some kind to lure prey in close, or to help them hide from the dragon's few potential predators. They are one of the larger species of dragons, and have very long necks and tails.

Leafy Snaptrapper
These look quite similar to the regular Snaptrapper, but their wings resemble orangey, dark green leaves that fall during autumn. This may be a tactic to help camouflage themselves in their seasonal habitat. Their neck, head and tail are also green. Their feet are green but orange near the claws. There are small orange bumps on the Leafy Snaptrapper's neck.

Abilities
The Snaptrapper is known to breathe a flammable mist containing methane, and can produce the smell of chocolate from their mouths to lure in potential prey. They also spit acid that can sting foes and even melt through metal. Superbly stealthy hunters, they can excellently camouflage themselves amidst dense vegetation, both to hide from larger dragons and from their prey. As shown in the Book of Dragons short, these dragons are capable of swallowing a Viking whole.

It can also release a horrid odor that can scare off even the most starving Titan Wing dragons as their self-defense.

Snaptrappers are not the most nimble flyers, a drawback of their heavy adaption for stealth-based hunting. However, their long, thin necks and tails are very flexible, similar to those of the Hideous Zippleback.

How To Train Your Dragon (film)
The Snaptrapper first appeared in the film within the pages of the Dragon Manual when Hiccup was trying to find information on Night Furies. He did not state the dragon's name, although the book read that Snaptrappers are extremely dangerous, and should be killed on sight.

Book of Dragons
In the Book of Dragons short, they are categorized in the Fear Class like the Hideous Zippleback. They attract prey with a sweet smell of chocolate, which emanates from all four mouths. Like all dragons, they shed their scales and talons, but these eventually regrow. Snaptrappers love rain and enjoy splashing in the mud which could be based off the fact plants need water and damp areas.

Behavior and Training
This large dragon has shown to love rain and enjoy splashing in the mud, which could be based of the fact plants need water and damp areas. As this could be a way for training this dragon if they see a Viking playing in the mud as well.

Titan Wing
Source: Dragons: Rise of Berk

Titan winged Snaptrappers have four heads and triple-spilt jaws with more teeth. They have developed a small tuft of pink fur-like structures at the back of their head. They have dark brown wings with some blue spots and yellow network vein like patterns, as such, their wings resemble dead leaves. Also, their neck is clearly segmented and has spines protruding from the back of their necks, all the way down to their tail, which eventually splits into two yellow tails.

Trivia

 * The Snaptrapper is based off a Venus Flytrap, and also resembles both the Hydra from Greek Mythology and, to a much lesser extent, a European dragon.
 * In the Book of Dragons Short, the Snaptrapper is said to use the smell of chocolate to lure its prey; however, chocolate was unknown in Viking times, due to it being native to the Americans. It would have been more realistic to use honey, which was known to Vikings and more likely, since it is made from the nectar of flowers which the Snaptrapper's heads resemble. This might be a shoutout to the books though, due to one of the villains trying to find America.
 * The Snaptrapper is one of the larger dragon species, like the Scauldron, Timberjack, Typhoomerang, Boneknapper, Screaming Death and the Whispering Death.
 * The only Snaptrapper that has been seen in the franchise so far is green, so this could indicate that most or all Snaptrappers are green or greenish in color.
 * In Dragon Tracker Part 4, the Snaptrapper was mislabeled as the Snappertrapper.
 * In the Book of Dragons Short, the Snaptrapper appears to be bipedal.
 * The Snaptrapper is one of the four dragons that doesn't have a forked tongue, along with the Flightmare, Snow Wraith, Razorwhip and the Woolly Howl.
 * Snaptrappers are the only dragons from the Book of Dragons Short that have not yet been in School of Dragons
 * it is possible that it might appear in race to the edge