The Katara are not an ethnicity truly. They are the result of recessive mutations passed down from ancient times and exist in the majority of bloodlines except for The Rugadhian. If you choose Katara this means you show substantial signs of the mutation: many horns, and significant skin color change. You should still select your true ethnicity and supply whether or not it is easy to determine under all the changes your body has experienced.
Highly Distinguishable
Katara are quite rare and you stick out like a sore thumb. You are easily recognized, when you enter a scene where you have some kind of fame or infamy someone always knows who you are. Who that is, is up to the GM and how that effects you is generally up to them as well. By default if it is fame you receive +1 ongoing when interacting with that person. If it is infamy you receive -1 ongoing when interacting with that person.