Space whale

Space whales are large enough to swallow Cybertronian starships whole. Presumably, these creatures roam space freely instead of being bound to a planet.

Fiction

The Transformers cartoon

At some point in time, a giant space whale swallowed the Jonagar, at that time piloted by Kup. Both ship and pilot were trapped inside the creature for three days, after which Kup managed to find a way to escape the creature's internals.

Kup recalled this tale after the events on Dread. Chaos