Rare ‘ghost shark’ may be captured on video

2009 footage, paper based on dives off California, Hawaii

Like its Greek mythological namesake, the chimaera — or “ghost shark” — is a mysterious, rarely seen creature with a patchwork of bizarre features.

Dwelling in the depths of the ocean, it has eyes that are pale and seemingly dead. Where teeth should be, the ghost shark has tooth plates, used to grind food instead. Its head is lined with cryptic dots, like remnant scars of ancient stitches.

Male chimaeras have retractable sex organs — on their foreheads. Its other nicknames — ratfish, rabbitfish, spookfish — hint at how bizarre chimaeras are in appearance.

And now, scientists believe they have captured on video a species of ghost shark that had never before been filmed live: the pointynosed blue chimaera. The video was taken in 2009 but only recently released by the Monterey Bay Aquarium Research Institute, along with a paper by researcher Lonny Lundsten and his colleagues.

Six years ago, researchers from the nonprofit sent an ROV, or remotely operated vehicle, on several dives off the waters of central California and Hawaii. The captured footage from depths of up to 6,700 feet surprised them: On film was what appeared to be a species of ghost shark previously only caught in the southwestern Pacific Ocean.

According to his paper, Lundsten consulted with three chimaera experts who watched the video from the expeditions. All believed the fish was a pointy-nosed blue chimaera.

Still, Lundsten and others from the institute can’t be certain that the fish captured on video is a pointy-nosed blue chimaera, despite their similar physical characteristics. Because of that, the paper refers to the fish as Hydrolagus cf.trolli rather than its scientific name, Hydrolagus trolli.

To be absolutely sure, researchers would have to capture the ghost shark and bring it back to the surface, the institute said. “This is much easier said than done, because these fish are generally too large, fast, and agile to be caught,” the institute notes. “If and when the researchers can get their hands on one of these fish, they will be able to make detailed measurements of its fins and other body parts and perform DNA analysis on its tissue.”

The pointy-nosed blue chimaera was discovered by researcher Dominique Didier Dagit in 2002, in the deep waters around Australia, New Zealand and New Caledonia.

Dagit, then an assistant curator of ichthyology at The Academy of Natural Sciences of Drexel University in Philadelphia, told The Associated Press in 2002 that she named her discovery Hydrolagus trolli after Alaskan artist Ray Troll because they shared a love for ratfish.

“It’s kind of nice to be able to name a species for someone,” Dagit said. “I thought, ‘my chance to name a fish for someone who’s really interested.’ ”