Sea Lamprey Petromyzon marinus
Lampreys belong to a group of vertebrates known as Agnatha which means 'jawless fish'. Their mouth is a toothed circular sucking disk. They have long elongated eel-like bodies. The back and sides of Petromyzon marinus have a distinctly mottled colour pattern with a brown-yellow dorsal and lateral colouring. Image: T. Lawrence Great Lakes Fishery Commission (Flickr).