Yep, that is Byrsella murex... it smells kinda fishy, I guess would be the closest match. Some of the Byrsella (Masdevallia; Section Coriaceae) species smell similarly unpleasant.
-Pat
PS: Sue, this species is harder to grow, but try other Byrsella species, like Byrsella peristeria or even Byrsella fractifelxa...