The dark and frigid ocean floor is home to some of the most bizarre organisms imaginable, including these Mariana Trench monsters, and this Lovecraftian long-arm squid with 26-foot-long tentacles. But one cursed crustacean crawling around down there, in the depths of a world mostly unseen by human eyes, has an especially alien invader-like quality to it. It’s the giant isopod, and it has a knack for latching onto the bellies of underwater vessels, munching corpse flesh, and generally acting like the kind of thing that could reproduce, spread, and infest ad infinitum if left unchecked.

Also, its blank and multi-faceted eyes look like they could steal your soul. Stare at the below picture for about 15 seconds if you need proof. Front view of the giant isopod, looking kind of like a “prawn” from District 9. Image: Wikimedia / Borgx

If you ever played with Armadillidiidae (a.k.a. pill bugs, a.k.a. roly polies, a.k.a. a million other nicknames depending on the region in which you live) as a kid, then you’re already familiar with Isopoda, an order of crustacean that woodlice and their relatives belong to. But while Armadillidiidae make for cute little friends that may join you out in your backyard while you’re reading a book or lounging against a tree, their relatively massive sea-dwelling cousins are horrific hard-shelled ocean demons that look like they’d gather around you only to drag you down into a dark hole that leads straight to Hell-o operator please give me number NOPE.

Giant isopods. Image: Flickr / Orin Zebest

The giant isopod, or Bathynomus giganteus, was first discovered in the late 19th century by French zoologist Alphonse Milne-Edwards, and since then, the species has become a well-documented member of the ocean, as well as, presumably, many a fisherman’s nightmares. The behemoth crustacean comes in two sizes, “giant” and “supergiant,” the latter of which can reach nearly 15 inches in length. And while that’s nothing compared to the largest crustacean on record, the Japanese spider crab — which can span 18 feet from claw to claw — you can still imagine how horrifying an encounter with a group of these would be.

Or better yet, forget about imagining. Watch this clip of a couple of giant isopods (as well as a few other hungry deep-sea scavengers) tearing apart the rotting flesh of a dead tuna as Sir David Attenborough’s soothing voice describes the carnage.

The giant isopods become so giant not because of any kind of Godzilla-like nuclear radiation, but rather deep-sea gigantism, or, said even creepier, abyssal gigantism. It’s the evolutionary tendency for deep-sea species to grow larger than their counterparts that dwell at shallower depths. With regards to deep-sea gigantism in crustaceans, the trend is thought to arise due to the colder temperatures of the deeper water — giant isopods are generally found at depths between 1,200 and 2,400 feet. The colder water may lead to increased cell size, as well as life span, both leading to increased maximum body size.

If you’d like to know where these beastly isopods spend their time so you can make sure to never ever go anywhere near them, you’re out of luck. They’ve been found in the Pacific, Atlantic, and Indian oceans, although, unless you’re hanging out in the Deepsea Challenger with James Cameron, you’ll probably never reach the depths at which they dwell. That is, unless you go to a Taiwanese seafood market, because yes, these bad boys are edible and people do, in fact, eat them. Why, here’s a GIF from YouTube user Tony Friedman’s own “Isopods for dinner” home video to help ruin your appetite forever.

What do you think about these giant isopods? Do these mega crustaceans look like they’d be perfect for invading Earth? Would you ever dare eat one of them? Let us know in the comments below!

Images: Wikimedia / Eric Kilby

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