First of all I have a soil mite issue, if you zoom on this pic you can see some. But today I noticed something I haven’t seen every not in person nor online. There’s one other leaf that has the same marks, I tried to wipe it with my thumb and it didn’t do anything. Could it be mold or some sort of PM? Could the soil mites, fu*king chilling on the leafs, have defecated on the leaf?
Occurring in just one leaf I would discard any deficiency or disease and would think in bug activity: could be thrips if there’s an irregular pattern or mites if they are just spots.
I would toss that leaf and carefully inspect the reverse with a scope, that last picture is not clear enough, keep it up with those attempts …
