There are some very green forms (var fusco-viride), and there is some variability within this form too, but the stripes in the petals are not as distinct as for these flowers.
More so than not villosum petals are darker in the upper half than lower half, with a poorly defined stripe (if present) down the center.
Even the greener forms of villosum tend to show some purple spotting at the base of the leaves and bracts, and the dorsal sepal is much more like an exul or duryi dorsal the way it curves forward (but I will admit that dorsal posture is highly variable too).