What killed off the Ankylosaurus dinosaur?

Ankylosaurus lived from 66.5 to 65.5 million years ago. They died out 65.5 million years ago during the K-T extinction event, the same event that killed off 75% of Earth's species, including all non-avian dinosaurs, the plesiOSaurs, pterosaurs, mosasaurs, and many, many more. The most widely accepted theory for their extinction is that a 6 mile wide asteroid crashed into the Yucatan Peninsula of Mexico, leaving a 100 mile wide crater. Enough dust and ash was launched into the atmosphere to block sunlight for months or years. Without sunlight, plants withered and died, and then the herbivores, like Ankylosaurus, starved to death. In turn, predators like Tyrannosaurus died out, too, because all of their prey disappeared.