I looked this up in a Dendrobium book - they have it listed under (synonymous with) sanguinolentum.
Sorry I didn't think to look this up before - I forgot I have that book
Regarding water: "Plants should be watered heavily in the growing season, but allowed to dry out for short periods during winter."
I have a couple Dens from the same section - they really do like their water. One will take slight drying in the winter, but the rest of the year I try to not let the media ever dry out.