COURTESY PHOTO / MARC HUGHES This new species of Grammonus fish was discovered in an underwater South Kona cave by marine biologist Marc Hughes.

Kona cave reveals new species of fish

KAILUA-KONA » Marine biologist Marc Hughes was about 100 feet into the dark recesses of an underwater South Kona cave in July when he saw what he had looked for since 1998: an unusual brown fish about 6 inches long.

With a flash of his hand, he scooped it up and put it in a pocket. "I was a scuba guide for years. You learn how to catch your fish," he said.

Shortly after Hughes made his catch, tropical fish authority John E. Randall at the Bishop Museum confirmed that Hughes had found a new species in the genus Grammonus.

Hughes informally announced the discovery last week as a means of giving recognition, and hopefully protection, to other sea creatures along the Kona coast that could be threatened by development.

Formal recognition of the fish, including bestowing a new species name, will take about a year, said Randall, who is writing a scientific paper on the discovery.

Hughes holds a degree in marine science and conservation biology from the University of Hawaii at Hilo. He takes the word "conservation" in that title seriously.

"This shows there's a very good chance that there are other species that we haven't discovered," he said.

Chemicals from development on land could have negative impacts in the many underwater caves formed from old lava tubes along the Kona coast, he said.

Hughes was studying micro-mollusks that look like sand in the South Kona cave near Kona Paradise subdivision in 1998 when he spotted the unusual fish and took a picture. Another photographer took a picture at about the same time.

The fish had a downturned mouth, and fins along its rear looked similar to an eel. Hugh showed the picture to Randall, who saw it was unusual but could not declare a new species on the basis of a photograph.

Hughes ended his nearly decade-long search for a specimen of the fish in April, catching one and sending it to Oahu via a tropical fish dealer.

The fish arrived dead, and the dealer, seeing no value in a dead fish, threw it away. Hughes returned to the cave and caught another one on July 21.

Shortly after Hughes found his second specimen, biologist Bronson Nagareda caught another one off Waianae and sent it to Randall.

Randall said other Grammonus fish include a species in the Mediterranean and another with the species name Robustus found from Japan through South Asia to the Gulf of Aden at the Horn of Africa.

Randall determined that the Hawaii fish are different partly by X-raying them and counting their vertebrae, different from other Grammonus species.

Grammonus fish give birth to live babies rather than eggs, unusual for marine fish, Randall said.