I recently got this plant as B. refractum from Tropical Exotique. There has been a couple of discussion about the identification of the related species. I think most of the photos on internet are unreliable, so I compared the illustrations in Swiss Orchid Foundation. I now know why it is so confusing. There are quite a bit of variations among different authors. Even within Seidenfaden's work, some features are different within species between different publications! For example, with B. kanburiense, the lateral sepal was small (around 2cm) in his 1973, but it is around 4-5cm in 1978. Also, the dorsal sepal shapes, lip shapes, lip hair patterns are different between 1973 and 1978. The plant I have seems to be close to B. refractum of G. King and R. Pantling (1898), but it doesn't quite match with Seidenfaden's (1973) B. refractum. Some aspects are close to B. kanburiense of Seidenfaden (1978). For example, in the 3rd photo, I noticed hairs in the back side (abaxial side) of the lateral sepal near the base. This was illustrated by Seidenfaden, but I didn't see this feature in the illustration of other species. Without reading the text description, it is difficult to ID (and I don't have the papers), but I think this is close to either B. refractum or B. kanburiense. I appreciate your opinion. All sepals are removed. Sepals and petals are removed (anther cap was gone during the handling). Dorsal and lateral sepals, right petal, and bract are showing the adaxial surface (front). The left petal is showing abaxial surface. The bottom side of the column and top side of the lip.