Lampreys (sometimes also called lamprey eels) are an order of jawless fish, the adult of which is characterized by a toothed, funnel-like sucking mouth.
While lampreys are well known for those species which bore into the flesh of other fish to suck their blood, most species of lampreys are not parasitic and never feed on other fish. The lampreys are a very ancient lineage of vertebrates, though their exact relationship to hagfishes and jawed vertebrates is still a matter of dispute.As food:
Lampreys have long been used as food for humans. They were highly appreciated by ancient Romans. During the Middle Ages, they were widely eaten by the upper classes throughout Europe, especially during fasting periods, since their taste is much meatier than that of most other fish. King Henry I of England is said to have died from eating "a surfeit of lampreys."
On 4 March 1953, Queen Elizabeth II's coronation pie was made by the Royal Air Force using lampreys.
Especially in southwestern Europe, and in the northern half in Finland, larger lampreys are still a highly prized delicacy. Sea lamprey is the most sought species in Portugal and one of only two that can legally bear the commercial name "lamprey" (lampreia)
The mucus and serum of several lamprey species, including the Caspian lamprey, river lampreys, and sea lamprey, are known to be toxic, and require thorough cleaning before cooking and consumption.
In Britain, lampreys are commonly used as bait, normally as dead bait. Northern pike, perch, and chub all can be caught on lampreys. Frozen lampreys can be bought from most bait and tackle shops.
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Recipe for Lamprey fish