Cryptozoology is derided for pseudoscience and fantastic claims, but when you consider some of the legends that have turned out to be real animals, it lends credibility to other potentially real cryptid creatures. And while the actual beasts are often more believable than the embellished monsters of lore, occasionally they can be pretty bizarre – whether a remnant of the Cretaceous period, a curious hybrid, or an inter-dimensional entity, some of these clandestine faunae are truly plausible.

That’s why we’ve compiled a shortlist of animals once-considered cryptids, that have now been proven real, using their stories as hope to strengthen our faith that the cryptid monsters we know and love may someday prove their existence to us.

But haven’t we discovered nearly every species of animal on Earth, you might ask? Far from it. In 2016 alone, scientists discovered roughly 18,000 new animal species. That’s not to mention that 80 percent of the world’s oceans are entirely unmapped, unobserved and unexplored, according to the National Oceanic and Atmospheric Administration (NOAA). So, who knows how many more could be down there.

Read through the first list of creatures proven to be real, then read the second list and determine whether there is enough evidence for the yet-to-be-proven-cryptids to have a basis in reality. We’ve provided cryptid pictures to help you along the way.

Cryptid Monsters Proven Real

Cryptid monsters are known to terrorize and typically reported by a significant portion of a population, or at least a large enough group to confirm that it is indeed an anomalous creature. In earlier years, these animals were brutes fought by hunters and fishermen on outings and were exaggerated to prove their machismo upon returning home. But eventually, these tales became backed by hard evidence, and today we know them well.

The Giant Squid

19th-century Scandinavian whalers spoke of the Kraken; an enormous squid whose appendages were found in the bellies of whales and said to be as thick as a ship mast. Fishermen continued to report attacks by these tentacled monstrosities, to the disbelief of landlubbers back home. But eventually, they returned with specimens or found their carcasses washed ashore.

In 1853, a large squid with a horny beak and large throat washed aground in Denmark, baffling local scientists. Johan Japetus Steenstrup, a professor of zoology from the University of Copenhagen, identified the creature as a giant squid.

Today, the giant squid is a scientifically accepted animal, reaching lengths up to 40 feet long. Their enormity is attributed to something called deep-sea gigantism; a tendency for deep-sea invertebrates to be larger than their shallow-water relatives. But the giant squid isn’t even the biggest mollusk of its kind, that title is reserved for the colossal squid, which reaches up to 46 feet in length.

The Platypus

The platypus is a rather bizarre-looking creature and if you attempted to explain it to someone before its discovery, they’d almost certainly believe you were mad. So, it’s an egg-laying mammal with the bill of a duck, the tail of a beaver, the webbed-feet of an otter, and the venom of a snake? Sure.

But now the platypus is a well-known creature, lending credence to the possibility of other cryptids that seem to be an amalgam of disparate species. When it was first presented to British zoologist George Shaw, he attempted to rip off its beak, believing it had been glued on. Eventually, he took scissors to the deceased animal, before he realized it was genuine. That particular specimen can be found to this day in a British museum.

The Frilled Shark

Sea serpents have stoked the fears of sea-farers for centuries, tormenting sailors and swallowing ships whole. From Texas to Norway, reports of sea serpents sprang up in local and national publications during the 19th-century, depicted as gargantuan snakes devouring unwitting mariners while they innocently roamed the sea.

Today, the frilled shark could be considered the closest animal to these horrific serpent tales, appearing much like those descriptions written in antiquity, though comparatively smaller. The frilled shark was discovered in the late 1800s by German ichthyologist Ludwig H.P. Döderlein, and later described by Samuel Garman as, “such an animal as that described is very likely to unsettle disbelief in what is popularly called the ‘sea serpent.’”

So, it’s a shark, but a frightening one at that, with 25 clusters of 300 sharp, serrated teeth, the Chlamydoselachus africana is one of those relics from the days when dinosaurs ruled the Earth. It’s also one of those deep-sea dwellers, which is part of the reason they are so rarely seen.