Look, if you were strolling down a lovely Australian beach and suddenly found a festering pile of flesh about as tall as Lebron James and almost 100 pounds heavier, you’d think it was a sea monster, too. Twitter exploded late Thursday over claims of the “Monster Fish” in Bundaburg after photos and a video of the seemingly unidentifiable decaying blob went viral.

The fish — if you can even call it that — is roughly 6 feet and 5 inches long and weighs about 150 kilograms, reported ABC on Wednesday. Whatever it was, it took John and Riley Lindholm, a couple taking a casual beach stroll, by surprise on Tuesday.

“I’ve seen a lot of fish, and a lot of big fish, but I’ve never seen anything like it,” John Lindholm told ABC.

Lindholm, who says he used to be a charter skipper and has plenty of experience with fish, can’t be blamed for his confusion. Because of its extensive decay — in the video below, you can see flies buzzing around the corpse — it’s barely clear which side is up.

Nevertheless, some keen-eyed fish fanatics noted its spiny dorsal ridge (down its back) is still intact, which was a hint that the corpse indeed belonged to a fish that was fairly familiar in those waters. While some people on Twitter suggested it might be a coelacanth — an ancient fish long thought to be extinct until it was discovered in 1938 — officials finally cleared up the confusion on Thursday. (For what it’s worth, coelacanth is a pretty good guess, but those fish don’t have the spiny dorsal ridge.)

In an interview with Australia’s NewsMail, Queensland Boating and Fisheries Patrol District Officer Geoffrey Fergusson solved the mystery: the fish was a Queensland Groper. Sometimes referred to as giant groupers (and occasionally as “gropers” in Australia), these fish are the largest dwelling reef fish in the world and have been known to grow to up to 8.8 feet and weigh up to 880 pounds. Monstrous, indeed.

Perhaps part of the reason that Lindholm and other fish enthusiasts were unable to quickly ID this thing is because it’s actually a protected species, meaning nobody is allowed to remove them from the water. That’s probably for the best, because the massive fish has been “implicated in fatal attacks on humans,” notes the Australian Museum, though when they’re left to their own devices along the east and south coast of the continent, they’re said to be pretty happy snacking on crayfish.

“The Queensland Groper is a no-take species,” said Fergusson. “In Queensland, catching and possessing this fish is prohibited.”

This case is closed, though it’s not likely to be the last time a so-called sea monster washes ashore and scares unsuspecting beach strollers. As recently as May 2017, an enormous rotting corpse on an Indonesian beach likewise led to loud cries of “sea monster,” though officials eventually figured out it was just a big, very dead whale. Ultimately, our seeming “sea monster” problem might not be that more corpses are washing ashore but that humans are increasingly out of touch with nature — in all its stages of life.