It must be malady time in my house!
This looks like rot to me. The spots are not wet, although it seems moist between the upper and lower leaf membrane (not paper dry). It has not spread any further, and plant has a clean new growth.
Should I be concerned about spread?
What type of rot(?) is this?
Any recommended treatment?
It seems that the higher the plant value, then the higher the susceptibility to problems that will totally wipe them out! Go figure! Hate to loose this plant: Dtps. Chain Xen Diamond "Celebration" FCC/AOS
Thank you for the feedback.