The differences between these two species are really distinct. If you see enough of the two species, you will instinctively know which is which.
The floral ratio of the lip to petals, the ratio of sepals/petals, the angle of the pedicel stem to flower and the color distribution as well as the distribution of the lip color are different between the two.
Vegetatively, the quad leaves on all sub types can be rolled lengthwise into a cigar. It’s an interesting phenomenon. This will tear the trianae leaves.
Also the ratio of flower size to plant size is different. Quad flowers are always smaller than the plant.