Those look great! I can only imagine how difficult taxonomy for those must be considering their similarity in the same habitat.
Initially I believe there was some confusion looking only to the flowers (although kautsliana flowers are bigger and the spikes are much longer).
If one considers also the plant itself, the differences are obvious.
I had a 50% chance of guessing wrong! I thought I had it right since you said kautsliana spikes are longer, and the front plant seems to have longer spikes. Photos can be deceptive!
__________________ Camille
Completely orchid obsessed and loving every minute of it....
Kautskiana's spikes are much longer (approx. 30 to 40 cm long) while harpophylla have, at most, 10 cm spikes. Harpophylla have long branches with a long leaf, as long as the branch. Those are not pbulbs, it means it isn't a drought tolerant plant.
Heres's some photos:
The kautskiana is a plany similar to a Cattleya:
The harpophylla looks more like a grass (the photo is not rotated, the plant grows naturally like this, with the branches hanging to the side.