About Lampreys

Petromyzontiformes are the lampreys — jawless fishes with a funnel-like, tooth-bearing oral disc instead of jaws.

Morphology. Eel-like, scaleless bodies with a single nostril on top of the head and seven gill pores. Adults of parasitic species use the oral disc to attach to fish and rasp flesh; non-parasitic species do not feed as adults. They lack paired fins and a true stomach.

Habitat & distribution. Temperate coastal and freshwater systems of the Northern Hemisphere; ammocoetes (larvae) burrow in silt of rivers for years before metamorphosing.

Ecology. Some species are anadromous; sea lamprey became an invasive pest in the Great Lakes after canal connections.