When this plant bloomed this week my mind went immediately to Dendrobium parishii. The plant is generally the right shape and there is a Dendrobium parishii in the collection. There will often be duplicates in a collection that is a few years old.
This plant has a tag that had been written in ball point. Part of my job in maintaining the collection is to catalog it. I do the best I can, but identifying orchids can be tough when the writing on the tag has completely faded away.
This plant is not Dendrobium parishii which blooms on old canes in the spring after a dry winter rest period. This has the general shape and color, but the lip is entirely different. I will only go so far as to say that one of the parents is Den parishii.
There is new growth just starting so I will repot and stake up the plant. I will add some rock to the mix to decrease the water holding capacity of the medium. I can't tell without looking at the roots, but the pot looks a bit large. Next year the blooming will be better.