Enlarge (credit: C. Marsicano) Gaiasia jennyae, a newly discovered freshwater apex predator with a body length reaching 4.5 meters, lurked in the swamps and lakes around 280 million years ago. Its wide, flattened head had powerful jaws full of huge fangs, ready to capture any prey unlucky enough to swim past. The problem is, to the best of our knowledge, it shouldn’t have been that large, should have been extinct tens of millions of years before the time it apparently lived, and shouldn’t have been found in northern Namibia.