Paleontologists often have to work in very demanding environments. A recent dig in Antarctica proved to be one of the most difficult paleontological excavations of all time, but luckily for the researchers who suffered through it, the results were a boon to paleontologists.
While massive sea lizards feasting upon plesiosaurs and giant prehistoric whales sounds like the stuff of old stop-motion adventure movies, that's exactly what researchers found while working in the remote islands off Anarctica's north coast. A team of Chilean researchers were digging in 66 million year-old rock on a small island chain near Seymour Island, Antarctica when they came across a 1.2 meter (4 foot) skull and humerus belonging to an unknown prehistoric sea creature.
According to the researchers’ published findings in the journal Cretaceous Research, the skull and humerus displayed physiological features that were unlike those in observed previous specimens:
We present a large, fragmentary skull and the humerus of a mosasaur [...] The material belongs to a large, adult individual with marked heterodonty as well as unusual humeral features.
The skull was initially believed to belong to other known genera of massive sea lizards until analysis and comparisons with other similar skulls determined that the remains belong to completely new genus of prehistoric sea lizards, Kaikaifilu.
Lead author Rodrigo Otero stated in a University of Chile press release that these remains indicate that the previously unknown super predator likely fed upon massive prehistoric whales and plesiosaurs which were also native to the area:
Prior to this research, the known mosasaur remains from Antarctica provided no evidence for the presence of very large predators like Kaikaifilu, in an environment where plesiosaurs were especially abundant. The new find complements one expected ecological element of the Antarctic ecosystem during the latest Cretaceous.
This new species, Kaikaifilu hervei, is now the largest known mosasaur discovered in the southern hemisphere. These carnivorous sea monsters had paddle-like limbs and massive powerful tails used for swimming. Several species of mosasaurs have been discovered in Antarctica, which once had a much more tropical climate and teemed with marine life in the late Cretaceous period.