These Creepy Ocean Creatures Are the Stuff of Nightmares

These hair-raising marine species will leave you feeling spooked on Friday the 13th and any other day of the year

When it comes to the creatures that call our ocean home, the first that may come to mind are probably magnificent whales, slow-swimming turtles or countless fish species. But our ocean is home to a mind-blowing number of incredibly diverse species, and not all of them are quite as charismatic as the well-loved iconic animals we’ve come to associate most closely with the sea.

From the deepest trenches of the sea to intertidal zones just off our coastlines, there are some lifeforms thriving in our ocean that are anything but cute and charming. Ready to meet some of our blue planet’s creepiest critters? Here are some of the absolute most *spine-chilling* marine invertebrates that call our ocean home. Read on to learn about just four of these most spook-tacular specimens of the sea.

Skeleton Shrimp

When I first laid my eyes on a photo of a skeleton shrimp, my first thought that followed was simple: there simply could not be a more appropriate name for this chillingly skeletal specimen. I quickly changed my mind when I learned that they’re also sometimes called the “praying mantises of the sea,” which seems less sinister to me (but I digress). If you look closely, you’ll notice that these crustaceans have tiny yet incredibly strong claws, which they use to reach out and grab prey when they’re least expecting it. These amphipods are typically small, normally reaching no more than around an eighth of an inch to two inches or so. Their usual go-to foods are things like algae and detritus (particles of dead matter that fall to the seafloor). These tiny critters are chilling to look at on a magnified level. Don’t believe me? The footage above from National Geographic just may change your mind!

Sea Spider

When I first learned of these spiders of the sea (which aren’t actually even spiders), I of course expected them to look similar to the arachnids that walk on land … but I did NOT expect them to have bodies reminiscent of the horrifying spider monsters from Stranger Things. The appearance of these creatures isn’t the only thing about them that will take you aback. These arthropods have what’s known as a proboscis: a type of elongated appendage that they use to suck up their food, slurping up energy by “sucking” nutrient-packed fluids out of sea jellies, worms and more. If you said, “ick,” don’t worry, I think that’s probably most people’s reaction. Science can be incredibly impressive sometimes … but it can also be disgusting, too.

Zombie Worm

Zombie worms? Yes, you read that right, and I truly do not think there could be a more apt set of nicknames for these creepy little critters. Thriving in the deepest parts of our ocean, these invertebrates also go by the nickname “bone-eating worms,” because they quite literally have a very specific preference when it comes to food. It’s important to know that these little worms don’t actually consume bones, however. Here’s what a daily meal for them looks like: when a dead whale or carcass of another large animal falls from the upper water columns to the seafloor, these worms play a very specific and important role in the biological breakdown of the creature’s remains. When it’s time to eat, these creepy-crawlers perforate the surface of the deceased host’s skeletal remains, utilizing acids to penetrate the outer layers of the bone to access the lipids that reside within the bone marrow. While this form of consumption may seem absolutely horrifying at first, it’s important to remember the critical part these zombie worms play in the cycle of life within our ocean. They are uniquely designed to thrive on bones, ensuring that the natural process of decomposition not only takes its course in an effective and efficient manner but also in a way that provides sustenance to other life forms on our planet.

Bloodybelly Comb Jelly

If you’re ready to learn about a truly morbid marine species, allow me to introduce you to this spectacularly scary ctenophore.  As you can see, the bloodybelly comb jelly gets its name from its belly that’s reminiscent of—you guessed it—blood. With a deep crimson coloration and mesmerizing movements, this ctenophore drifts through the waters of our ocean with majestic (and slightly petrifying) grace. But don’t be fooled, friends, because these jellies are anything but gentle or benign. Dubbed by Monterey Bay Aquarium Research Institute (MBARI) as “voracious predators,” these comb jellies have seemingly unquenchable appetites, primarily feasting on a menu of copepods, young fish and the larvae of various marine species. They’ve even been known to consume some of their ctenophore cousins if they can manage to wrangle them, too! Another fascinating factoid: apparently, their deep red coloration is intended to mask the glow of any creatures they consume that may be bioluminescent, so as to not let other prey know that they’re dangerous. Sneaky, Mr. bloodybelly comb jelly. VERY sneaky.

Well, friend … which of these creatures creeped you out the most? For me, it was definitely the sea spider! While so many of these species may send chills up your spine, don’t forget that every single one of these animals plays a special and important role in the delicate balance of life within the sea. Interested in learning more about the wild, wonderful (and somethings weird) life forms that call our ocean home? Be sure to follow along with us on Facebook, Twitter and Instagram with all sorts of fun facts about our blue planet.

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