Basia is the great grandmother of Sheldon J. Plankton. She only appears in the comic, A Plankton Family Tree.
Description
She is an old plankton with four curled arms and legs, white hair, and stooped posture.
Biography
At some point, she married Seymour.
Later, they were run out of their hometown for evil scheming and had to move to Bikini Bottom.
Here, they had Alvin and Ella.
Role in the comic
She is only a representation of Plankton's family tree.