Doedicurus

The Doedicurus was a armadillo like mammal that lived in north america. It had a spiked tail that was used to whack pretadors, kinda like the Ankylosaurus. It was a herbavoire, meaning it ate plants.

Its name means "pestle tail", referring to how, if the spikes were removed, it would resemble a pestle.

it was the largest known glythadont.