"It's a bizarre-looking fish with a pointed snout," said Lonny Lundsten, a senior research technician at Monterey Bay Aquarium Research Institute (MBARI) in California. "It has a long, pointed, tapering tail, relatively large eyes, [and] it's almost entirely grayish-blue."
The rare, deep-sea fish — called a "ghost shark" for its appearance, but also known as the pointy-nosed blue ratfish — made its video debut after researchers recorded the animal via remotely operated underwater vehicles (ROVs) off the coasts of Hawaii and California. The videos, six in all, provide the first evidence that this species of ratfish lives in the Northern Hemisphere, Lundsten told Live Science.
The videos were taken between 2000 and 2007, but it was only in October that researchers published the findings in the journal Marine Biodiversity Records, said Lundsten, who co-authored the study with two of his colleagues.
|The Monterey Bay Aquarium Research Institute's ROV (remotely operated underwater vehicle) caught footage of six different ghost-shark individuals. Notice that the fish are swimming over rocky, rather than soft sediment.|
Despite naming the newfound species, researcher Dominique Didier, a professor of biology at Millersville University in Pennsylvania, had never seen a live specimen. Instead, she and her colleague studied 23 dead H. trolli specimens caught as bycatch by trawlers (deep-sea fishing boats that catch marine animals with large nets) in the southwestern Pacific Ocean. These fish were all found in the Southern Hemisphere off the coasts of Australia, New Zealand, New Caledonia, and the Lord Howe Rise (a deep-sea plateau) and Norfolk Ridge formations, Lundsten said.
But Didier did get a chance to see the MBARI videos and confirmed that the fish in the footage with wing-like fins were likely H. trolli, Lundsten said.
Lundsten added that H. trolli's Frankenstein-like stitches are actually sensory organs that cover the fish's entire body, especially its face. These organs can sense minute movements and vibrations in the surrounding water, which helps the fish hunt prey, said Dave Ebert, who co-authored the study with Lundsten and Amber Reichert, a graduate student of marine science at California State University (Cal State). Ebert is also the program director of the Pacific Shark Research Center at Cal State's Moss Landing Marine Laboratories.
In addition, male ratfish "have a strange sexual-related organ that's on the top of their head," Lundsten said. "It's a club-shaped thing that has spines on it, and it's used for grasping and better positioning the female during copulation."
Read more at Discovery News