A ‘Fire Wolf’ Fish Found in Unusual Deep-Sea Ecosystem

Deep in the Pacific coast of Costa Rica lies Jacó Scar, a methane seep ecosystem that is a chimera of sorts. Unlike other methane seeps found before it, Jacó Scar’s geochemical activity produces lukewarm water that enables a diverse group of organisms from both colder seeps and scalding hot hydrothermal vents to thrive. Recently, scientists have discovered a new species of fish, called an eelpout, that is a resident of Jacó Scar. This newly identified species of fish could help researchers understand how the unique ecosystem developed.

The discovery of the eelpout fish species was described for the first time on January 19 in the journal Zootaxa. The eelpout fish is the first vertebrate species found at Jacó Scar and could provide significant insights into how the ecosystem evolved. Jacó Scar is a unique place that is home to various microhabitats, and it is teeming with different organisms, making it a “really diverse place,” according to Lisa Levin, a marine ecologist at Scripps Institution of Oceanography in La Jolla, California.

Newly Identified Species of Eelpout Found at Jacó Scar

The discovery of the eelpout fish species was accidental. During an early exploration of Jacó Scar, the team discovered and collected one of the fish, but they did not recognize it as a new species. Several more specimens were captured during later submersible dives, and Charlotte Seid, an invertebrate biologist at Scripps, brought the fish to ichthyologist Ben Frable, also of Scripps, for formal identification.

Frable recognized that the fish was an eelpout, a diverse family of fish that can be found worldwide at various ocean depths. Eelpouts can be challenging to identify because the physical differences between species can be subtle, and the team had trouble determining the exact type of eelpout. They eventually sent X-rays, pictures, and one of the fish specimens to eelpout expert Peter Rask Møller of the Natural History Museum of Denmark in Copenhagen.

Møller determined that the fish was a member of the genus Pyrolycus, which means “fire wolf.” The other two known Pyrolycus species live far away in the western Pacific and have different physical features, making the mystery fish a new species. The team named it P. jaco.

Comparing P. jaco to Vent-Living Relatives May Provide Clues to Adaptation

The discovery of P. jaco raises questions about how the known Pyrolycus species came to live so far apart. The new finding could be due to the fact that methane seeps are more common than previously thought on the ocean floor. If some methane seeps are lukewarm like Jacó Scar, the new species could have used them as refuges while moving east. By comparing P. jaco to its vent-living relatives, researchers may be able to figure out how it adapted to living in the tepid waters of Jacó Scar, providing clues to how other species living there also adapted.

The eelpout fish is just one of the many species that make up Jacó Scar’s composite ecosystem. Clams typically found at cold seeps and bacteria found at hydrothermal vents also reside in Jacó Scar. The ecosystem is a “mixing bowl” of species found in other parts of the world, and researchers are intrigued by how this eclectic bunch interacts. The discovery of the new eelpout fish species could provide significant insights into how this unique ecosystem formed and evolved.

In conclusion, the discovery of the new eelpout fish species in Jacó Scar, a unique methane seep ecosystem off the Pacific coast of Costa Rica, is a significant breakthrough in marine biology research. This new species of fish could help researchers understand how the unique ecosystem developed and provide insights into how other species living in Jacó Scar adapted. The discovery raises questions about how the known Pyroly.