There was something I saw at a Parent's friends house briefly when I was passing through where it was the desert or possibly another planet. A turtle-like creature fell down this small rounded pit and was trying climb out. A tentacle came out of the center and slowly extended towards the turtle-creature, eventually sticking to it. It picked it up and then slowly lowered it into the sand. The camera cuts to an area near the pit and a cartoon-like sound of the monster eating the creature, which ends with the creature spitting out the shell and the shell landing in front of the camera, with the inside completely missing and bloody.

This would be in the late 80's, and I've never been able to figure out what the hell it was that I watched all those years ago.