Black specks on Chondroryncha Ledyana

[theroc1217]

I have a Chondroryncha that's got some black specks on the undersides of the leaves. I didn't think much of it, but recently a leaf turned yellow and fell off, and now another one is as well. We've been in a heatwave here, so I think that might be it. I've moved it inside now, but I'm wondering if it might be disease instead of the heat?

[WhiteRabbit]

good luck!