Space Squids. Yeah. Space Squids, Ye heard me!
Each family is a herd. Each herd is part of a larger Mind. The Minds will meet in times of emergency or new contact with a speices. They are mildly telepathic.
THEY EAT SPACE WHALES
Also, due to life in space being harsh and all, they have devolped a secondary stomche capable of digesting metals and other inorganic compounds. So you know that nice new ship?
They can eat it.