Texas Confederate Pension Index:
Starnes, Richard Aarron
Claim #49187
County: Travis
This is his Confederate pension application. It should tell you what you are seeking, at least it should point you to what unit he served with.
There is a link at the top of this page to our Military Records Research Services You can order his pension application and service records there. It will also help to support this board.
Good luck and let us know if we can help further.