2 New Species of Eel-Like Ancient Fish Discovered in Napa River, Alameda Creek [Study]

Researchers discovered two new species of eel-like fish called lamprey in the rivers of California. The discovery marked the amount of diversity in the area.

New Species of Lamprey Discovered in California

A new study from the University of California, Davis, found two new species of lamprey, a type of ancient fish. They both reportedly belonged to the Lampetra genus. Lampreys date back over 350 million years.

Lampreys are a kind of blood-sucking fish without bones. They are identified by their long, tooth-filled, sucking mouth and lack of jaws.

The Klamath River basin, San Francisco Bay, and Sacramento-San Joaquin River basin were among the 19 regions the Davis lab investigated. They then proceeded to ascertain whether the species' true distributions and current estimates of the species matched.

The Lampetra and the Entosphenus genera are classified as "of special concern" in the state. Therefore, this discovery is extremely significant because scientists had long thought that the populations of these species were falling in the Western United States. Among the many problems they face are water contamination and habitat destruction.

While the species is found in many states, the discovery of two new species in California raises the possibility that it is considerably more ubiquitous than previously thought by scientists. Before this inquiry, eight species of lamprey were known to exist in California.

"We found diversity that has never been reported," said Ph.D. candidate Grace Auringer, the study's lead author and a member of the UC Davis Genomic Variation Lab.

"We found two groups of fish in Napa River and Alameda Creek that are very genetically different from other samples along the West Coast. This is a really understudied group of fish."

What Is a Lamprey Fish?

Lamprey is the common term for fish that resemble eels and are elongated. They belong to the family Petromyzontidae and are distinguished by their cartilage-based primitive vertebrae, slimy skin without scales, unpaired fins, an adult-retained notochord, and a circular, jawless mouth with teeth on the oral disk.

The scaleless, eel-like creatures are between 15 and 100 centimeters (6 and 40 inches) in length. They feature a single nostril on top of their head, one or two dorsal fins, a tail fin, well-developed eyes, and seven-gill holes on either side of their body.

Although lampreys are commonly referred to as "lamprey eels" due to their superficial resemblance to eels, they are not closely related to eels, which belong to the class of jawed, bony fish (Osteichthyes).

Both freshwater and anadromous (primarily living in the oceans but returning to freshwater to breed) lampreys undergo a dramatic transformation in freshwater during their larval stage. Numerous lampreys are parasitic, penetrating other fish's skin to obtain blood.

They begin as ammocoetes or burrowing freshwater larvae and feed on microbes. At this stage, they have primitive eyes and no teeth. After a few years, they mature into adults and usually enter the water to start a parasitic life in which they cling to fish by their lips and consume the host's tissues and blood. Lampreys return to freshwater to breed, construct a nest, spawn (laid eggs), and eventually perish.

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