These fish-like animals are characterized by not having true jaws or paired fins. There are freshwater and anadromous members of the family distributed in the cooler water areas of the northern and southern hemispheres. Pacific lamprey, Lampetra tridentata, Remarks: The Eel River is named for this eel-like animal. A parasite of other fishes that enters local rivers and streams in the spring and early summer. Identification: Eel-shaped, with a circular, sucker-like mouth. Smooth skin and seven gill openings on each side. Brown to dark gray in coloration. Maximum length about 75cm. Range: Baja California north to the Bering Sea and Japan. An anadromous form found in all the tributaries flowing into the Bay.