These long, eel-like, jawless fish are free-swimming predators on other fish. Lampreys hatch in freshwater and many live their lives entirely in freshwater. Some lampreys migrate to the sea, but must return to freshwater to reproduce. Lampreys have a sucker-like mouth that lacks a jaw.
Drawing of several lampreys. From the Image Gallery at lycos.com. (Five Lampreys, Lydon, A. F., 1879 Animal Kingdom: Vintage Illustration).
Sea lamprey on lake trout. Image courtesy of Great Lakes Fishery Commission (http://www.glfc.org/slft.htm), used by permission.
Sea lamprey mouth, close-up. Image courtesy of Great Lakes Fishery Commission (http://www.glfc.org/slft.htm), used by permission.
by M.J. Farabee
Information provided by: http://www.emc.maricopa.edu