Yes, indeed, it certainly was Oliver J. Semmes (another OJ, you ask???), and, although an artillery Captain, and the son of Raphael, he was placed in command of the DIANA, for a very short period.
I can provide the actual references if anyone needs it.
So both Raphael, and one of his sons, Oliver, had commanded a vessel in April, 1863. I believe another son, Raphael, junior, was a midshipman in the CS navy.