Dragonsmana's Cryptid files:[link]
Cryptid File 064 Giant Anaconda "Megaconda"
Length: unknown, perhaps up to 100ft
Territory: The Amazon Jungle
Description: Giant anaconda snake
People are afraid of snakes. And for good reason; they are highly evolved killing machines, some with venom potent enough to fell an elephant, some constrictor strong enough to pulverize bones. The anaconda is of the latter, a massive constrictor made famous by it's size and a series of horror films. Most people think that the huge man-eaters depicted in said films are pure fiction.
No one knows for sure what is hidden in the depths of the amazon, or any other jungle. The limits to how large an anconda can get are unknown; some hypothesize, that with enough prey available, and enough time they could grow to a hundred feet long! A terrifying prospect, considering that regular-sized ones have been found having eaten human children whole.