The lake lamprey, Entosphenus macrostomus, also known as the Vancouver lamprey or Cowichan lamprey, a recent derivative of the pacific lamprey, is a species of freshwater lamprey endemic to two North American lakes: Lake Cowichan and Mesachie Lake in Vancouver Island, Canada. The lamprey was originally called the Vancouver Island lamprey, until an error in filing shortened it to the Vancouver lamprey. The alternate common name of "Cowichan lamprey" was coined and promoted by the species' describer, Dr. Dick Beamish, who originally identified the species in the 1980s.