The Dinosaur-Era KRAKEN That Hunted Mosasaurs...

Added: 2026-05-22

[00:00:00]The rulers of the seas during the latest phases of the Cretaceous were the marine reptiles, right? Well, maybe. In the Cenomanian to the Campanian stages of the Cretaceous, just before the arrival of Tyrannosaurus Rex, a hidden predator lurked along the coastlines and deep waters of Canada. It's only in 2026 that paleontologists have shed light [music] on what this animal really may have been. A monstrous macropatorial octopus.

[00:00:27]Scientists have very recently concluded that this animal may have been capable of reaching truly monstrous sizes. But just how much of that can we believe? In today's video, we're going to be diving into the Cretaceous seas to meet one of the true terrors of the ancient deep.

[00:00:40]Hold your breath as we come face to face with Nais Hagati, quite possibly the largest sephalopod in the fossil record.

[00:01:05]While in modern times we associate the squids with attaining immense sizes amongst the sephalopods, the Neatus was an octopod. Today its largest cousin is the giant Pacific octopus. On occasion, this cold water predator can grow an arms span of around 4 1/2 m, an impressive feat for any modern animal.

[00:01:23]Meanwhile, the more distantly related deep water giant and colossal squids can grow even larger, exceeding 10 m. This makes them the largest living invertebrates. But what about the nameus Hagati?

[00:01:35]This submarine colossus may, and we use the word may with emphasis there, have been capable of reaching up to 19 m from the tip of its mantle to the end of its [music] tentacles.

[00:01:45]For reference, that's almost as large as two school buses parked end [music] to end, or as long as the average five-story building is tall. As you can imagine, if these [music] size estimates prove accurate, this was not an animal to be taken lightly. But what did such an extravagant animal look like? Well, paleontologists initially believe that the Neatus belonged to the order vampir, which today contains only the vampire squids. You may be familiar with these animals already. They evolved in the Jurassic period and [music] resemble octopuses and squids to an extent, but in reality are neither. They tend to inhabit deep, temperate, and tropical oceans between 6 [music] to 900 m into the depth. The very largest individuals today only tend to grow [music] up to 30 cm in length. It was only as recently as the April of 2026 [music] that paleontologists reclassified namatuis into the order octopod. Within that order, namatuis sits within the suborder serata or [music] the serate octopuses.

[00:02:41]Their closest living relatives then are the deep water dumbo and flapjack octopuses. Comparatively tiny to their monstrous ancient relative, these sephilopods are famous for their huge earlike fins situated at top their mantles [music] and the neatus is believed to have possessed such features in life too. These fins provide their primary means of locomotion which helps them conserve energy in the deep sea.

[00:03:03]While living serate [music] octopuses tend to prey upon small crustaceans and worms, namatus may have favored much larger prey, but we'll take a look at exactly what later in this video.

[00:03:19]Nameus' story does not begin in 2026.

[00:03:22]However, neither does it begin with the species Namachus Hagati. In 2008, paleontologist Kazushig Tanab and team were excavating the rocks of the Penda formation which lies in the Nao geological group of Vancouver Island, Canada. The excavation was a great success in yielding fossil sephalopods from the late Cretaceous period. Not only did they manage to discover, describe, and name the genus Nameatus, [music] but they also discovered two species of Paleoceris, Pacifica and Hagati. Nameus Gilletki was formally described first and subsequently became the type species of the genus. Later in 2010, [music] namachis' range expanded into the other side of the Pacific with remains of a new species, Nameuthus [music] Yokatai, having been unearthed by Tanab in the Yizo group of what is now Hkaido, Japan.

[00:04:10]Then in 2015, it would be joined by another species the name of Hikidai from the same area. These smaller species are thought to have closely resembled the vampire squids of today's [music] deep seas, even if they would eventually prove to be only distantly related to them. Everything changed for the genus just a few weeks ago in the April of 2026. However, perhaps the most fascinating paleontological discovery of the year so far was made when Dr. Naoki Ikagamian team reviewed the remains of Natheus' beak that had been unearthed by Tanab [music] and made a series of quite literally huge conclusions. Ikagami synonymized the two genera that had been unearthed in 2008 under the same genus.

[00:04:49]Paleocerus is now considered to be invalid and Paleoceris Hagati was formally changed to Nameus Hagati.

[00:04:57]Then Ikagami compared the sizes of these fossil jawbones to those seen in living seephalopods in order to calculate a potential size for this animal. Using alometric scaling, [music] a method that counts for the fact that some animal body parts don't always grow proportionately to the rest of the body.

[00:05:12]The team concluded that an adult namachis hagati may have been capable of reaching smaller sizes of around 7 m and larger sizes of around 19 m. These calculations are based on the fact that the nameus' preserved lower jawbones measured just over 86 mm in length, around 1 and a half times as large as those seen in the modern-day giant squid. It is important to note, however, that these sizes very may well come down in the future, especially if additional fossil material is recovered. It's very hard to accurately calculate the size of a prehistoric animal if all you have to go on is one bone. And since Iami has calculated the size of Namachuis Hagati from reference of its beak alone, we could see these speculative calculations change [music] drastically over time.

[00:05:55]Still, a sephalopod capable of reaching lengths of 7 m is not to be snubbed.

[00:05:59]That's almost still twice as large as the biggest living octopus is and almost as large as [music] a giant squid. This would not be the first time such a downsizing has taken place, even recently. In 2023, the remains of a giant whale, Peruetus colossus, [music] were discovered in the eene age rocks of Peru. Initially, paleontologists suggested that this animal may have rivaled or even exceeded the living blue whale in size and weight, but subsequent studies brought maximum weight estimates down [music] from 340 tons to 114 tons.

[00:06:28]A massive animal nonetheless, but not quite the Leviathan it was initially believed to be. Will the same happen with the name of Chuis? We'll just have to wait and see. Either way, the term the Cretaceous Kraken seems to have stuck.

[00:06:45]For the rest of this video, however, let's run with the idea that the name of Chuis was indeed an animal of these monstrous 19 m proportions. The fossil record does in fact back up that this animal was a giant predator and that it fed on animals with hard skeletons. The preserved jawbones of Nameachus Hagati show unusual wear patterns that researchers claim cannot be attributed to the abrasion to the rocks caused by coastal waves. Therefore, this wear and tear may have been caused by the animals violently grabbing and biting into their targets, which may have consisted of large marine vertebrates.

[00:07:17]For years, the large marine reptiles mosasaurs and plesiosaurs are believed to have been the top predators of the lake cretaceous seas. Researchers of Nanachuis [music] however have suggested that the animal may have been a direct competitor to if not a predator of these often immense carnivores. The authors even note that namachis may have been an example of convergent evolution with vertebrae apex predators as both groups evolve colossal sizes in order to take down the largest animals of the oceans.

[00:07:43]Other paleontologists have cast out doubt on this again, however, and note that the presence of wear and tear on the fossilized beaks did not necessarily coincide with these animals taking on the roles of apex predators in their ecosystems. Nameus Hagati individuals of smaller sizes likely prayed upon fish and other sephalopods such as ammonites as they drifted through the northern Pacific, but it's not outside the realms of possibility for larger individuals to have been specially adapted marine reptile hunters. Large octopus species today, such as the giant Pacific octopus, have been observed using stealth and camouflage to ambush sharks.

[00:08:15]They restrain them with their arms before digging in with their sharp beaks. Some have even been seen to drown the sharks they hunt, weaving their flexible arms in and out of the prey gills to prevent water passing over them. It's a speculative idea at this stage, but could namatuis have utilized a similar technique? It's a terrifying thought to imagine an octopus the size of a building descending on a huge mosasaur only to wrap its arms around the reptile's face and drag it to the seafloor in a violent struggle.

[00:08:43]Modern octopuses are often strong for their size. So, what would a truly giant one have been capable of? Still, a marine reptile as large and as powerful as a mosasaur may even have been too much for even the biggest of the name to handle. Some species were capable of reaching up to 18 meters. And those jaws were some of the most prominent hunting tools to appear in the animal kingdom to date. Many were ambush predators, but unless an [music] adult nameus was really caught by surprise, there's every chance that they could have put up a good fight. It brings to mind the modern scenes of sperm whales battling in the deep oceans with giant squid. While the sephalopods occasionally end up as dinner, the whale is often left heavily scarred following the encounter.

[00:09:26]The Neatus went extinct around 72 million years ago. And prior to that time, the seas were filled with large and often very strange animals. Aside from the mosasaurs and plesiosaurs we've already touched on, [music] Nameothis may have encountered the likes of Zeactinis, a widespread and common carnivore in the Cretaceous seas. This huge fish capable of reaching between 5 and 6 m, [music] has been nicknamed the bulldog fish on account of the strange appearance of its face. Zifactinis is often portrayed hunting smaller fish as well as the long- necked oceangoing bird Hesperonis.

[00:09:57]Elsewhere, the Lake Cretaceous seas harbored the gigantic paraposia, a huge ammonite with a shell diameter of a meter and a half by just under 2 m.

[00:10:07]The wear and tear seen on the Neatus' bones may well have been the result of hunting animals such as this, which were by far the biggest of their kind.

[00:10:14]Smaller names may have found ammonites such as these difficult [music] to tackle. However, they were capable of retreating into their shells when danger approached, and larger individuals may have been capable of fighting back with beaks and flexible arms of their own.

[00:10:27]Just above the seas soared many species of terasaur. The legendary pteranodon and its cousin Nicttosaurus were just a few examples of flying reptiles that thrived at the same time as Nameachu.

[00:10:37]The fossil record shows instances of terasaurs falling victim to marine animals as they descended to the surface to catch fish. It's highly speculative at this point, but could namatuis have plucked stray terasaurs from the surface only to drag them down to the depths and consume them there? The same could be said for many species of dinosaur that often swam from land mass to lamb mass during the lake Cretaceous. The idea of a giant sephalopod dragging a large theropod down to the depths to its doom is like something out of a horror movie and yet not beyond the realms of possibility.

[00:11:12]While our understanding of the name of Toothus may well change in the future, it was still an amazing animal nonetheless. To see such a bizarre Kraken-like animal come to life before our eyes is something that very few of us imagine would happen in our lifetimes. To know that Nameothus of these sizes may well have been out there during the age of the dinosaurs is truly the stuff of wonder. Let us know your thoughts on the nameus in the comments section of this video. Do you think that size will stick or do you think like peruse it will eventually be downsized?

[00:11:38]As always, thank you so much for watching and we'll see you in the next video.