I looked at a couple of websites and books, I not so sure. There are many varieties of D. speciosum of which only one was posted on http://www.orchidspecies.com/indexdendroc.htm Your flowers appear to have longer flowers (sepals) than most of the pictures that I found. Closest that I saw was D. tetragonum (one of several varieties, others are darker in colour) or maybe a hybrid of the two species. Shaun
