Sea serpent

A sea serpent is a sea monster, possibly a dragon, that has the appearance or at least partial appearance of a serpent.

Although such creatures are legendary, history tells of many strange sightings of such creatures.

Plinky asked her father Krim if the Sucker Tube that tried to suck them in was a sea serpent, to which he told her that it wasn't alive, it was a machine...some form of human technology.