Skekfish
this species of fish-like creature was a hybrid of carbon- and silicon-based lifeforms. They were named for the way they "swam" through soil, and could easily move through solid rock. They accomplished this by their swimming motion, which placed their razor-sharp, metallic scales in contact with the surrounding material. These scales literally scraped away material. Skekfish had no eyes, and hunted purely by their sense of hearing. When they attacked larger prey, the skekfish would first jump at their prey, using their knife-like bodied to slash at it. Skekfish were known for their swift speed, voracious appetites and incredible reproduction rate, and it was theorized that a colony of skekfish could eliminate the major fauna on an undeveloped planet in little time. Whenever a colony of skekfish ran out of food, they reproduced one last time, laying their eggs in the carcasses of their prey. These last eggs, if undisturbed, could survive for thousands of years before hatching again. The only known defense against these creatures was the use of ion weapons, which caused them to explode.