The deseado dancer (Compsotyrannus rancori) is medium sized tyrannosaur and rather large for south American standards. During the dry season, they molt, loosing all but the feathers. These agile dinosaurs live in small pockets across southern South America. The geographic and behavioral restrictions placed by the Andes mountains and constant threat from deinonychosaurs separates Compsotyrannus into two species.  The more common of the two, C. rancori often engage in complex mating dances, using leaps, head bobbing, and skips. Hence the name dancer.