now, as summer approaches it was exposed to much stronger sunlight and the leaves underneath has turned yellow. i put it in a kind of terrarium to increase coolness as i read that spicerianum prefers cooler environment.
I would not be super concerned with the dying of the bottom leaf as this is a trait with paph, loosing the old making room for the new. The ripple in the leaves is inadequate watering. But the spots to me appear to be sunburnt, unless there was poor air circulation in the terrarium and this could possibly be fungal leaf-spot disease...typically they begin as yellow areas on the leaf's underside and with them darkening the spots are visible on both sides. If this is the case spray with a fungicide, remove the most damaged. My way of determining if its sunburnt or virus is to touch the leaves and see if they are pitted (virus) if the leaves are smooth so to speak (sunburnt) without pitting, odds are it's sunburnt.
Hi , If the terriarum is exposed to sun it will get hot , also not enough air flow . I would take it out of the terr.
If getting to much sun just move it to a shadier area . The lower leaves will in time turn brown and die they are the old ones . The spots are probably from being to hot . Gin
The bottoms leaves always die off at this time of year...
Those spots look like sun burn, the cells look like they have collapsed.
BTW paphs rarely get viruses and when they do they have been noted not to show any symptoms, but rather slowly die off sometimes. Large collections (I believe in Britain) were surveyed and paphs were the least affected of all the genera in the collection.