FORT JOHNSON — Maybe the eeriest shark of all is one of the smallest — the lantern shark. It glows in the dark.

The shark has bioluminescence, the shine that a firefly has. The shark lights up its belly, and can change the intensity at different depths so that, when looked at from below, it has the same glow as the water above it.

Meanwhile, its dark back makes it look like the bottom black to anything above.

“So no matter the depth, they blend in with light from the surface or the dark looking down,” said biologist Gavin Naylor, with the Hollings Marine Laboratory.

The camouflage, naturally, means prey can’t see it until the shark is alongside.

“By then it’s too late,” Naylor said.

Naylor’s shark research team is trying to get a lantern shark caught off the East Coast, to complete a specimen set that has lantern sharks from every other place they are found on Earth.

There’s just a few problems. Lantern sharks are deep-sea creatures, found at depths of nearly 1,000 feet or more. And they’re small, rarely getting much longer than 5 inches.

The team’s other specimens came as by-catch from deep-sea fishing. But there’s not a lot of that going on at those depths, well offshore.

The team is appealing to deep-sea anglers to bring back a lantern if they come across one.

To help or for more information, call 1-814-409-8507.

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