Athena is "Other" on her map
Also the combined forces for chapter 6 Fire Emblem called all units "Altea"; likely because Marth and Hardin agreed that the former will assume command.
Before the Archanean League is established, Marth's army is called "Altea" in the status screen of FE11.
Once you reach chapter 5, Nyna's party is called "Archanea".