Lampreys /ˈlæmpreɪz/ (sometimes inaccurately called lamprey eels) are an ancient extant lineage of jawless fish of the order Petromyzontiformes /ˌpɛtroʊmɪˈzɒntɪfɔːrmiːz/, placed in the superclass Cyclostomata. The adult lamprey may be characterized by a toothed, funnel-like sucking mouth. The common name 'lamprey' is probably derived from Latin lampetra, which may mean 'stone licker' (lambere 'to lick' + petra 'stone'), though the etymology is uncertain. Lamprey is sometimes seen for the plural form. (Source: Wikipedia.org, CC BY-SA)