The Tetrapodophis only made a brief appearance when Arlo and Spot encountered it on their journey. It first appears when Arlo started eating berries and the Tetrapodophis fell on him and Arlo shaking it off. Confronted by the Tetrapodophis after falling off the cliff, Spot was able to wrestle it to save Arlo from the predator, thus retreating. It isn't seen for the rest of the film after this.
Soundtracks:The Good Dinosaur Video Games:Disney INFINITY: 3.0 Edition • Dino Crossing Books:Read-Along • Hello, Arlo • Golden Book • A Friend in the Wild • The Junior Novelization • The Journey Home • Spot Leads the Way • Creatures and Critters! • Crash, Boom, ROAR! • A Wild Adventure! • A New Best Friend • A Berry for Arlo • A Boy Named Spot/A Dino Named Arlo • Big Golden Book