Black Spots on Pseudobulbs

[NYCorchidman]

No worries, many ondontocidium or other intergenerics will have this ( either a few specks or quite often covering the entire surface almost!) on their pbs.

The kind of marks you should worry look very different. These "natural" markings are on the very outer layer of the tissues on the pbs.
Sometimes you will see disease marks or brown rots, which usually look water soaked or deep-seated by visual inspection.