Although I think this is not a pest, I didn't knew where to put it in these forums.
This is a close up of the medium of my Laelia vasconcelosiana. I believe this is some kind of fungus.
The vendor told me there was no need to repot becaus the medium is one year old only.
It might be, or might not! Not to mention that it might even be beneficial - but I doubt it.
Orchiata bark is naturally populated with penicillium and trichoderma species, and there are inoculants that can be added to provide growth stimulation an infection prevention, and they all produce hyphae that "extend the reach" of the plants' root systems, absorbing water and nutrients and "injecting" them directly into roots via mycorrhizae.
What you have is more likely a pathogenic, wood-decomposing fungus, so repotting is the best course of action.
I'm reluctant to repot it...this a species discovered less than 10 years ago. It's rare to find it for sale and the information I get from the web is contradictory.
I will wait to see how it develops what seems to be a new growth.
Is it just the light, or is the base of the orchid black? If that’s not normal, it might be worth some exploratory poking around to make sure the roots are okay before adopting a wait and see.