Can I play as Batarian, Elcor, Geth, Hanar, Rachni or Volus in Mass Effect 3's multiplayer mode? So far only Asari, Human, Krogan, Quarian, Salarian & Turian have been announced.
According to the Mass Effect wiki
There are only 7 playable races
As a side note, only humans can be every single class. The wiki also has a table for class/race combinations.
As of the Resurgence DLC pack(free), the following races were added:
As of the Rebellion DLC Pack(free), the following races were added:
As of the Earth DLC Pack (Free)
As of the Retaliation DLC Pack(free)
http://sticktwiddlers.com/2012/03/12/mass-effect-3-secret-multiplayer-characters-leaked/ You may find that interesting.