Xenarthra includes the anteaters, sloths, and armadillos. In the past, these families were classified together with the pangolins and Aardvark as the order Edentata. It was realized that Edentata contained unrelated families and was invalid by cladistic standards.

 

Aardvarks and pangolins are now placed in individual orders, and the new order Xenarthra was created to group the remaining families (which are all related). The name Xenarthra means "strange joints", and was chosen because their vertebral joints are unlike those of any other mammals.