black on pseudobulb?

[stefpix]

Hi
I have an Encyclia tampensis I got a couple of months ago.

seems to grow ok - longer leaves / new roots but what looks like the oldest pseudobulb has some strange reticulation and is darker in color.

I wonder if it may be fungus [ I sprayed fungicide as a precaution].
If it is should i just remove that pseudobulb?
the other pseudobulbs look healthy and new to my eye.
It came like this when I purchased it. just now looks slightly more wrinkly.

Also my Dendrobium spectabile has one pseudobulb with a dent and looks a bit darker.
The plant looks over all healthy, growing a new cane and new roots.
I attach photos -
I hope if that look is pseudobulb look is aging...