The generic name is composed of the Latin words animatus ("living" or "animated") and arx ("fortress" or "citadel"), referring to its armored nature. In particular, the name is a reference to a comment made by paleontologist R. S. Lull about ankylosaurs, that as "an animated citadel, these animals must have been practically unassailable..."[1] The type species is the only one known so far, and is called A. ramaljonesi after its discoverer, Ramal Jones. His wife, Carol Jones, also discovered the contemporaneous dinosaur Eolambia nearby.