The Titanoboa is an upcoming snake. It is currently not in development and will be worked on later. It will only be an NPC in survival mode because of it's lifestyle, sit in the exact same spot for hours and wait for prey to come. However because it also would chase fish it might be added for players later.
In Real Life
Titanoboa was a large species of extinct snake known to live in what is now La Guajira, Colombia. It was theorized to eat crocodiles, turtles, and fish. This slithering tyrant would bite its prey then wrap around and squeeze the life out of its victim and devour it hole. It has surpassed Gigantophobis as the largest snake since it's discovery.
Size: 13-14m, weight 1.1 ton