Life reconstructions of Kyhytysuka sachicarum from the Early Cretaceous of Colombia. Credit: Dirley Cortés
A new 130-million-year-old swordfish-shaped marine reptile fossil clarify the development of hypercarnivory of these last-surviving ichthyosaurs.
A group of international scientists from Canada, Colombia, and Germany has found a brand-new extinct marine reptile. The specimen, an amazingly preserved meter-long skull, is among the last making it through ichthyosaurs– ancient animals that look strangely like living swordfish.
Life restorations of Kyhytysuka sachicarum from the Early Cretaceous of Colombia. Credit: Dirley Cortés
” This animal developed a special dentition that permitted it to eat large victim,” says Hans Larsson, Director of the Redpath Museum at McGill University. “Whereas other ichthyosaurs had little, similarly sized teeth for feeding upon small victim, this new types customized its tooth sizes and spacing to develop an arsenal of teeth for dispatching big prey, like huge fishes and other marine reptiles.”
Life restorations of Kyhytysuka sachicarum from the Early Cretaceous of Colombia. Credit: Dirley Cortés
” We chose to call it Kyhytysuka which equates to the one that cuts with something sharp in an indigenous language from the region in main Colombia where the fossil was found, to honor the ancient Muisca culture that existed there for millennia,” says Dirley Cortés, a graduate student under the supervision of Hans Larsson and Carlos Jaramillo of the Smithsonian Tropical Research Institute.
Ichthyosaurs (Ancient Greek for “fish lizard”– ichthys implying “fish” and sauros suggesting “lizard”) are large extinct marine reptiles.
Dirley Cortés dealing with the skull of Kyhytysuka. Credit: Dirley Cortés
The huge picture of ichthyosaur advancement is clarified with this new species, the researchers state. “We compared this animal to other Jurassic and Cretaceous ichthyosaurs and had the ability to specify a brand-new kind of ichthyosaurs”, states Erin Maxwell of the State Natural History Museum of Stuttgart (a former graduate trainee of Hans Larssons lab at McGill). “This shocks the evolutionary tree of ichthyosaurs and lets us evaluate brand-new concepts of how they evolved.”
Skeleton of Kykytysuka compared to a human for scale. Understood bones remain in white. Credit: Dirley Cortés
According to the researchers, this species comes from an important transitional time during the Early Cretaceous duration. “Many traditional Jurassic marine environments of deep-water feeding ichthyosaurs, short-necked plesiosaurs, and marine-adapted crocodiles were prospered by new lineages of long-necked plesiosaurs, sea turtles, large marine lizards called mosasaurs, and now this beast ichthyosaur,” states Dirley Cortés
Photo and physiological analysis of the skull of Kyhytysuka sachicarum. Credit: Dirley Cortés.
” We are discovering lots of new species in the rocks this brand-new ichthyosaur originates from. We are testing the idea that this area and time in Colombia was an ancient biodiversity hotspot and are utilizing the fossils to better understand the evolution of marine environments throughout this transitional time,” she includes. As next steps the scientists are continuing to check out the wealth of new fossils housed in the Centro de Investigaciones Paleontológicas of Villa de Leyva in Colombia. “This is where I grew up,” states Cortés “and it is so fulfilling to get to study here too.”
Referral: “Re-appearance of hypercarnivore ichthyosaurs in the Cretaceous with separated dentition: modification of Platypterygius sachicarum (Reptilia: Ichthyosauria, Ophthalmosauridae) from Colombia” by Dirley Cortés, Erin E. Maxwell and Hans C. E. Larsson, 22 November 2021, Journal of Systematic Palaeontology.DOI: 10.1080/ 14772019.2021.1989507.
“We compared this animal to other Jurassic and Cretaceous ichthyosaurs and were able to specify a new type of ichthyosaurs”, states Erin Maxwell of the State Natural History Museum of Stuttgart (a former graduate trainee of Hans Larssons lab at McGill). Credit: Dirley Cortés
“Many traditional Jurassic marine communities of deep-water feeding ichthyosaurs, short-necked plesiosaurs, and marine-adapted crocodiles were prospered by new lineages of long-necked plesiosaurs, sea turtles, large marine lizards called mosasaurs, and now this beast ichthyosaur,” says Dirley Cortés
” We are finding lots of new types in the rocks this new ichthyosaur comes from. “This is where I grew up,” says Cortés “and it is so satisfying to get to do research here too.”