Here’s a small collection of bizarre animals that we hope some of you may have never heard of. The animal kingdom does love variety - and feel free to add your own in the comments section.

Pacu Fish

Pacu is actually a common name for numerous different fish species that are related to piranhas. Pacus are vegetarian fishes that are traditionally found in the major river systems of South America. They look a bit like a piranha, but they’re usually a lot larger than your average piranha. So what’s so interesting about these fish, they look pretty uninspiring- right? WRONG.

Peering into the chomping jaws of these fish will reveal their totally bizarre set of gnashers that look scarily like human teeth. They have these teeth because they normally feed on hard things like nuts and seeds which is why they have been nicknamed nutcracker fish, but a few joke articles came out stating they were also “testicle-biting” fish, as they supposedly left men in Papua New Guinea castrated after they took a shine to their crown jewels. After one was caught in Sweden, a fish expert Henrik Carl joked in a news article “They bite because they’re hungry, and testicles sit nicely in their mouth,” but it wasn’t meant to be taken seriously, so don’t worry- they won’t actually eat your knackers, they’re safe around these guys.

Image credit: SWNS.

Dumbo Octopus

There are 18 different species of octopus within the genus Grimpoteuthis which are commonly referred to as a “Dumbo octopuses” due to their characteristic ear-like fins that make them resemble Disney’s Dumbo. These enigmatic cephalopods are a pretty rare sight since they usually dwell in deep waters ranging from 400 meters to 4,800 meters, but the few times they have been spotted has revealed that they usually eat crustaceans and worms. They’ve also been observed around deep sea hydrothermal vents, which are areas on the sea floor where hot and mineral rich fluids spew out due to volcanic activity.

Check out this awesome video of a graceful Dumbo octopus filmed at a depth of around 2000 meters.

Spiny Orb Weaver Spider

These spiky spiders look pretty damn awesome. There are numerous different species of spiny orb weavers, all belonging to the genus Gasteracantha. One such example is G. cancriformis which is found in some parts of the US, Central America and some parts of the Caribbean. They’re around 2-9mm in total length and come in a variety of colors and shapes, and some have colored legs too.

Gasteracantha fornicata. Image credit: Amos T Fairchild, via Wikimedia Commons

Gasteracantha dalyi. Image credit: L. Shyamal, via Wikimedia Commons.

Pink Fairy Armadillo

I included these guys because LOOK. AT. THEM. Isn’t that just the darn cutest yet totally weird thing you’ve ever seen? It’s like a rabbit wearing a shield. With alien paws.

The pink fairy armadillo, or Chlamyphorus truncates, is the smallest species of armadillo, measuring a mere 10 centimeters in length on average. You’ll find these guys in Argentina, digging holes in dry grasslands or sandy plains. They live underground but surface at night to find food, which mostly consists of ants.

Image credit: Cliff, via Wikimedia Commons.

Penis Snake

This bizarre looking animal (Atretochoana eiselti), which shockingly is neither a penis nor a snake, was only known from two preserved specimens until it was rediscovered in 2011 while part of the Madeira River in South America was being drained. It’s a caecilian amphibian that can achieve a total length of around 80 centimeters, making it the biggest known caecilian. Little is known about these hilarious looking animals, but caecilians are limbless and generally navigate via their sense of smell.

Image credit: Musa Sudai, via Wikimedia Commons

Proboscis Monkey

I’m sure most of you know about this monkey, but whilst on the topic of things that resemble the male genitalia I thought I’d include it.

These monkeys are endemic to Borneo, living in jungles and mangroves. They feed on unripe fruit because the sugars in ripe fruit ferment in their digestive system and cause bloating so bad that it can be fatal. The males use their large, penis-like noses to woo potential mates, but it’s also thought that they may serve to amplify calls. Unfortunately, these monkeys are under threat due to deforestation and also poaching because they are considered a delicacy by some, and they’re listed as an endangered species.

Image credit: Bjørn Christian Tørrissen, via Wikimedia Commons.

Hagfish

Hagfish are primitive marine creatures that live deep at the bottom of the ocean. They look a bit like an eel and have no jaws, spines or scales and have exceedingly poor eyesight; most rely on their sense of smell. Over 60 different species of hagfish are known which can vary in color from pinks, browns or greys. They often scavenge off dead animals, but they can also latch onto passing live prey, burrowing inside and eating their way out. Grim. One of the most interesting features of hagfish is their ability to produce a slime that can suffocate predators such as sharks. Just a tiny amount of slime will dramatically expand in size when it comes into contact with seawater, and sometimes the hagfish themselves can get tangled up but they wriggle into knots to escape from it.

Check out this awesome video of a hagfish sliming predators:

Sunfish

Check out these humongous dudes. Sunfish, or mola mola, are huge bony fish that can weigh up to a whopping 2,250 kilograms and can reach around 4 meters in length. Their rather odd appearance is due to the fact that their back fin doesn’t grow and instead folds into itself. They typically feed on jellyfish and small fish, and can be found in both temperature and tropical oceans.

Image credit: U.S. National Oceanic and Atmospheric Administration, via Wikimedia Commons.

Blobfish

I’m sure many people have seen pictures of these hilarious fish, but I had to mention them, just because they’re awesome.

The blobfish, or Psychrolutes marcidus, is a deep sea fish that can be found at depths of between 600-1200 meters in Australian waters. Their jelly-like flesh is less dense than water so they can happily float above the sea floor without having to do much. They’re not the most efficient predators, so they just hang around and wait for food to come to them. They’ve been voted one of the world’s ugliest animals. Aww give them a break it’s not their fault!

Image Credit: Simon Elgood, via Flickr, used in accordance with creative commons attribution 2.0 (CC BY-ND 2.0)

Yeti Crab

Kiwa hirsuta, which has been nicknamed the yeti crab (for obvious reasons), is a crustacean that was discovered back in 2005 900 miles south of Easter Island at a depth of 2,300 meters. Although there isn't a great deal of information on these curious animals, they seem to dwell around deep sea hydrothermal vents. As you can see, their pincers are covered with blond, hair-like strands. It transpires that these hairs are riddled with bacteria, which some believe may serve as a food source for the crustacean.

Image credit: Wanida. W, via Wikimedia Commons.

Sunda Colugo

​Galeopterus variegatus, also named Sunda Colugo or the Sunda Flying Lemur, is a nocturnal and arboreal (lives in trees) mammal endemic to Indochina and Sundaland. These animals possess large membranes of skin called patagiums that extend along the limbs, allowing them to glide along distances of up to around 100 meters; given that these animals are only around 40 centimeters in length that's pretty impressive skills! The mottled coloring of these animals also makes them look a bit like the lichen of a tree and therefore helps to camouflage them.

Image credit: Norman Lim, National University of Singapore.

Tufted Deer

The Tufted deer (Elaphodus cephalopus) is a small species of deer found in high altitude forests of Burma and China. They have a prominent tuft of hair on their heads which gives them their name, but they also look like an adorable vampire. Their fangs are long upper canines, which are similar to what you'd find in their close relative the muntjac. They're very territorial animals, and although they have small antlers the males use these sharp canines to fight over both territory and mates.

Image credit: Wikimedia commons.

Fossa

Ok, so everyone's seen the amazing film Madagascar, which includes these animals. But we feel they were a bit misrepresented. While it might look like a cat, fossas (Cryptoprocta ferox) are actually very closely related to the mongoose. They are indeed endemic to Madagascar, and they're the largest carnivores on the island. These enigmatic predators are solitary animals and they will pounce on anything they can sink their retractable claws into. Unfortunately they are endangered because their habitat is threatened by deforestation.

Image credit: Ran Kirlian, via Wikimedia Commons.

Sarcastic Fringehead

Yes, you heard correctly, there is an animal called a sarcastic fringehead, and no- it's not just an English person with bangs. These crazy creatures (Neoclinus blanchardi) are found in the Pacific ocean off the coast of North America. Under normal circumstances they don't like to flash the goods, but when threatened they open their huge colorful mouths and show off some sharp teeth as a sign that you don't mess with these bad boys.

Here's a (slightly hilarious) video of two fringeheads fighting over their homes with their mouths:

Gerenuk

​The Gerenuk (Litocranius walleri) is a species of antelope found in numerous countries such as Tanzania, Kenya and Somalia. They are pretty easy to recognize because they have a very long neck and long skinny legs. Oh, and you know, the fact that they can stand on their hind legs! This allows them to be able to reach vegetation that other antelopes can't. And don't they look smug about it.

Oh, hey, how's it going, just grabbing some foliage. No big deal. Image credit: Michael Despines.

So there you have it, some pretty funky animals that grace us with their presence on this diverse planet!