SAN DIEGO (KSWB) — Another ultra-rare deep-sea fish has washed up this month on a beach in California, the Scripps Institution of Oceanography at UC San Diego said Tuesday.

Officials say scientists were notified Dec. 10 about a deceased female Pacific footballfish found at Swami’s Beach in Encinitas, in San Diego County. The creature measures nearly 13 inches long and weighs 5 pounds, Scripps spokeswoman Brittany Hook said in a news release.

It is the third time in the past month a deep-sea fish was reported near an area beach, including the second such Pacific footballfish, which was photographed on Nov. 13 at a beach in La Jolla. An unusual 4-foot lancetfish also was found dead Dec. 1 on the sand at La Jolla Shores.

“Experts don’t have any evidence to theorize why these fish are washing ashore in Southern California, but are interested in learning more about the specimens that have been collected or any new ones that might wash up,” Hook said.

The institution called the most recent find “extremely rare,” noting only 31 known specimens of the specifies have ever been collected. Tissue samples from the fish are being collected for genetic analysis and its stomach contents are expected to be examined by researchers with Anela Choy’s lab at Scripps.

Researchers are reminding the public that if they happen to come across an unusual find at the beach, “do not take it home.” Instead, notify a lifeguard and contact the Scripps Institution of Oceanography at scrippsnews@ucsd.edu or by phone at 858-534-3624.