That's my guess. I've seen some photographs from out west that were interesting as far as the blend of Union and Confederate. Then there are some comutation uniforms that make my eyes bug out of my head at.
What a wonderful officer's coatee. Yes, the shoulder boards are unusual; but not unheard of, especially in 1862/3. The attire, to include the bloomed hat, suggest a connection with J.E.B. Stuart's Cavalry, in which Maryland troopers participated.