Northern Lampreys [Petromyzontiformes]
Description
The order Petromyzontiformes, commonly known as Northern Lampreys, includes all species of lampreys. These jawless fish are characterized by their eel-like bodies, absence of paired fins, and the presence of a unique oral disc instead of jaws. Lampreys are known for their parasitic lifestyle during the adult stage, where many species attach to and feed on the blood of other fish. However, not all species are parasitic, with some living off detritus. Lampreys are found in temperate regions and are of both marine and freshwater species. Marine representatives, such as the sea lamprey (Petromyzon marinus), migrate to freshwater to spawn. Lampreys have a significant ecological impact and are also of interest in evolutionary biology studies due to their primitive features.