elementals are not arcanna, they are theyre own race seperate from arcanna, one of the main reasons is that elementals cannot be charmed by bstmasters, also is the support that the arcanna ability doesnt stop any attacks, also there is no dmg increase or decrease when arane circle is in effect
As of the december patch, all "killer" and "circle" effects now add an automatic paralyze-like effect to the referred-to mob type. It gives a "[mob] is intimidated by [player]'s presence" message. Note that dragoon-type mobs can use this against dragoons' wyverns also. Killers and Circles and Paralyze can all be stacked.
Everyone keeps saying that Elementals are arcana, but I regularly solo farm Elementals for clusters and in 30+ Elemental fights they have never once gotten the paralysis, so I am very skeptical that these are Arcana.