Without a flower, it is sometimes difficult to nail it down to a species.
I'd just stick to calling it a Dendrobium in Section Aporum.
Although it is more likely it is a Dendrobium in Section Aporum, as an fyi, sometimes certain species of Eria have this kind of vegetative growth as well. Eria and Dendrobium are closely related.
Also as a heads up, these can grow fairly slow. They aren't the fastest growing Dendrobiums out there.
Update on this old thread to anyone who it might help. This plant bloomed for me for some reason, and I'm now confident it is indeed a dendrobium anceps.
To back up a bit, I found out this plant had no roots soon after I originally made this thread. I did the sphag and bag method without success for several weeks. Eventually I just left it on a tray, where it started putting out roots in the middle of the plant. From the same segment, it put out two tiny new growths. It was also growing from the tip a bit. I keep it unpotted on a tray and spray it with water regularly. Recently it decided to issue out a single bloom. This is one of the weirdest plants I've ever owned.