This pencil image is visual development for my book project, and is a creature evolved from this body plan. [link]
This is a giant air breathing creature evolved from a land living ancestor. Water is gulped whale shark style from near the surface and squeezed into pouches in either side of the flattened head. Once the mouth is closed, the water is forced out a long slit on the top side of the head, passing a modified filtering mouth part which traps small animals. To breath, the creature nears the surface and extends a fleshy breathing tube from a small orifice on the right-hand side of the head.