Mysterious deep-water shark caught on video, but ‘Uber crab’ steals the spotlight

A sixgill shark navigates the lightless depths near the Channel Islands.

A mysterious type of deep-water shark has been documented twice within two days by scientists using an ROV to probe the sea floor around California's Channel Islands.

Both bluntnose sixgill sharks – one slightly smaller than the other – appeared in the lights of the ROV last week at depths of 700 feet and 1,000 feet, respectively.

But during the second encounter, at Santa Cruz Island, a large crab stole the spotlight when it moseyed into center stage while toting another crab in its claws. (In the video posted above; the crab enters at 1:07.)

This prompted scientists monitoring the camera feed from aboard the E/V Nautilus to wonder aloud, and humorously, about the peculiar sight.

"Is that a taxicrab?" one of the scientists asks in the video?

A large crab totes a smaller crab as it walks across the sea floor.

"It's an Uber crab," another responds.

The scientists did not identify the crab species, but there's no mistaking the shark species.

Sixgill sharks, which can measure to about 18 feet, possess six gill slits on each side of their heads, versus five gill slits for most other shark species.

The prehistoric-looking sharks, which resemble fossil shark species that date back 200 million years, are not well researched because they typically inhabit depths of 600 to 3,000-plus feet.

A sixgill shark swims into the lights of an ROV 1,000 feet deep at the Channel Islands.

Sixgill sharks prey largely on fish, smaller sharks, seals, squid, rays, and crabs.

The sharks are generally sluggish, but as the E/V Nautilus video shows, they possess a certain grace as they navigate the lightless depths. (Video showing the first encounter can be viewed here.)

The E/V Nautilus is conducting a yearlong study of the Eastern Pacific, from Canada to Mexico's Revillagigedo Islands.

More about sharks from GrindTV

Juvenile great white sharks joined by 15-footer in shallows off Capitola; photos

28-foot shark spotted off Trump's golf course

Close encounters galore as great white shark tour debuts off SoCal; photos