Study has shown that a huge swordfish-like creature, with an arsenal full of teeth, lived in the shallow waters of Colombia 130 million years ago.
Researchers from McGill University reanalysed fossilised remains that were unearthed near Villa de Leyva in Colombia’s Boyacá department back in the 1970s.
The specimen has a stunningly preserved, 3-feet-long skull, and is an ichthyosaur, an order of marine reptiles that lived from 250–90 million years ago.
In 1997 experts assigned the fossil the genus platyterygius. This grouping, some claim, is used to identify species that aren’t found anywhere else.
Yet fresh study of the skull, which is held in the Colombian National Geological Museum in Bogotá, has revealed that it belongs to a new genus — ‘Kyhytysuka’.
According to the team, this revelation is helping us understand the family tree of the Ichthyosaurs and the evolution of its members.
Scroll down to view video
Study has shown that the giant, swordfish-like creature was 130 million years old and swam through the waters of Colombia.
The specimen has a well-preserved, 3-feet-long skull (pictured, top, and illustrated, bottom), and is an ichthyosaur, an order of marine reptiles from 250–90 million years ago
Hans Larsson (vertebrate paleontologist from Canada’s McGill University) and his collaborators conducted the study on Kyhytysuka.
Professor Larsson stated that the animal’s unique dental system allowed it to take large prey.
The new species includes a variety of tooth sizes that are able to handle large prey like fish and reptiles.
For example, while Kyhytysuka’s front-most teeth were long and slender, and optimised to grip smaller prey, the saw-toothed dentition further into the jaw seemed to have evolved to shear the creature’s victims.
Meanwhile, Kyhytysuka’s back set of teeth were short and robust, suggesting they were used to crush prey — a conclusion supported by the reinforced connection between the brain-case and skull bone hints at an increased bite force.
Furthermore, the team’s analysis indicated that, while the marine reptile would have been unable to move its jaws much side-to-side, it could open its mouth to a colossal gape of 75°, which would have allowed it to swallow very large prey.
Experts assigned the fossil to the 1997 genus Platypterygius. Some have claimed that this group is used to categorize species not found elsewhere. Yet fresh study of the skull, which is held in the Colombian National Geological Museum in Bogotá, has revealed that it belongs to a new genus — ‘Kyhytysuka’ (artist’s impression)
Hans Larsson from McGill University, paper author and vertebrate Palaeontologist said: ‘This animal developed a unique dentition to allow it to eat larger prey. The author continued that other ichthyosaurs ate small prey but had equal-sized teeth. This new species, however, modified the spacing and sizes of its teeth to make it more capable of consuming large prey like fishes or other marine reptiles. Pictured: the groupings of Kyhytysuka’s teeth
‘We compared this animal to other Jurassic and Cretaceous ichthyosaurs and were able to define a new type,’ said paper author and palaeontologist Erin Maxwell, formerly of McGill but now based at the State Natural History Museum of Stuttgart.
‘This shakes up the evolutionary tree of ichthyosaurs and lets us test new ideas of how they evolved.’
The fact that the specimen has relatively small eye sockets (‘orbits’) and a linear jaw line indicates that the creature would have swum in shallow waters.
‘We decided to name it Kyhytysuka, which translates to “the one that cuts with something sharp” in an indigenous language from the region in central Colombia where the fossil was found,’ said paper author Dirley Cortés, also of McGill.
This genus name, he added, honours ‘the ancient Muisca culture that existed there for millennia.’
“We compared it to other Jurassic ichthyosaurs” said Erin Maxwell, paper author and palaeontologist, who used to be at McGill and now resides at the State Natural History Museum in Stuttgart. Pictured: an illustration of Kyhytysuka’s varied dentition and sizeable gape of up to 75°, allowing it to swallow large prey
Dr Maxwell said that the discovery’shakes up evolutionary trees of ichthyosaurs’ and allows us to test new theories about how they evolved. Pictured: an artist’s impression of Kyhytysuka’s mouth
‘We decided to name it Kyhytysuka, which translates to “the one that cuts with something sharp” in an indigenous language from the region in central Colombia where the fossil was found,’ said paper author Dirley Cortés, also of McGill. Pictured: isolated teeth of Kyhytysuka (top row) and teeth in cross section (bottom row), shown in both photograph and illustration
According to the team, Kyhytysuka comes from an important period of transition in the Early Cretaceous, during which Earth was coming out of a relatively cool period, sea levels were rising and the supercontinent Pangaea was cleaving into two.
The Cretaceous also began in the wake of a global extinction event that altered the composition of both marine and terrestrial ecosystems.
‘Many classic Jurassic marine ecosystems of deep-water feeding ichthyosaurs, short-necked plesiosaurs, and marine-adapted crocodiles were succeeded by new lineages,’ said Ms Cortés.
They included long-necked plestiosaurs and sea turtles as well as large marine lizards called mosaurs. And now, the monster ichthyosaur.
The genus name of Kyhytysuka, Ms Cortés added, honours ‘the ancient Muisca culture that existed there for millennia.’ Illustration of an illustration of the ichthyosaur. The silhouette of a human diver is shown to scale.
Researchers from McGill University reanalysed fossilised remains that were unearthed near Villa de Leyva in Colombia’s Boyacá department back in the 1970s
‘We are discovering many new species in the rocks this new ichthyosaur comes from,’ Ms Cortés continued.
“We test the hypothesis that the region of Colombia in the past was a biodiversity hotspot. We are now using fossils to understand how marine ecosystems evolved during this period.”
With this study complete, the researchers are now exploring the wealth of new fossils housed in Villa de Leyva’s Centro de Investigaciones Paleontológicas.
‘This is where I grew up,’ Ms Cortés noted, adding: ‘It is so rewarding to get to do research here too.’
Journal of Systematic Palaeontology has published all of the findings.