Rare Megamouth Shark With Unusual Bioluminescent Mouth Caught Near Japan

First, it was the rare goblin shark caught last week by a fisherman in the Gulf of Mexico -- only the second on record -- now it's a megamouth shark, also rare, that's gaining attention.

It is unclear when exactly the 13-foot, nearly 1,500-pound megamouth was caught, but it was recently dissected and put on display at the Marine Science Museum in Shizuoka, Japan.

Image source: Nippon TV

The shark, caught off the city's coast at almost 1,000 feet deep, is only the 58th one on record, according to Nippon TV.

Watch NTV's footage of the shark:

According to the Western Australian Museum, megamouth sharks were first discovered in 1976. Despite how it might look, the shark's giant mouth isn't for chomping on big fish. The shark actually eats plankton.

"Their mouth is bioluminescent," University of Miami marine biologist David Shiffman told Business Insider."Some scientists believe this is used to attract their food."

Discovery detailed more about the rare megamouth in last year's "Shark Week":

While the megamouth is a more recent find, let's jump back to the goblin shark for a moment. Though the 18-foot shark attracts the eye the most in photographs, below nestled in the pile of shrimp are quite a few giant isopods.

This discovery, according to the Houston Chronicle, has some speculating that the shark and the crustaceans were part of an ecosystem around a dead whale carcass.

"While I think [the] goblin shark is cool and all, look at all those freakin' giant isopods!" marine biologist Andrew Thaler tweeted of the photo over the weekend.

While I think @WhySharksMatter's goblin shark is cool and all, look at all those freakin' giant isopods! pic.twitter.com/D5gMUElHxk

— Andrew David Thaler (@SFriedScientist) May 4, 2014

According to NOAA, the shark was accidentally caught by shrimp boat captain Carl Moore off the Florida Keys, after snapping pictures he released the fish back into the Gulf.