The bottom line is this:
* The ICZN says Diplodocus longus is the type species (and so YPM 1920 is the type specimen).
* Actual sauropod workers use CM 84 as the type specimen for all practical purposes.
That means that reality and the Commission differ. There are only three possible outcomes:
1. The Commission changes its mind and admits that CM 84 is the type.
2. Sauropod workers stop referring to CM 84 and start comparing putative Diplodocus material to YPM 1920.
3. We continue as we are today.
We know from the rejection of the petition that #1 is not going to happen. I can tell you for myself, and for the sauropod workers that I have collaborated with, that #2 is not going to happen. That leaves #3: the issue will continue to sit there â either ignored (which I think is just fine) or occasionally bubbling up to no effect (as in the present thread).
I have made my peace with the fact that all the extant malacologists on the Commission want to think YPM 1920 defines what the name Diplodocus means. I no longer feel the need to persuade them they're wrong. But they most certainly have not persuaded me that they are right, and I am just going to go on my merry way.
-- Mike.