An orchid of the aranifera section. It is therefore quite close to the much more common spider orchid. The petals are in principle quite wide and purple in color (entirely or at the margin). The basal field is very dark and more so than the labellum, which gives a second criterion since in O. aranifera, this field is lighter or concolorous.

O. passionis flowers at the same time as O. aranifera, which leads to hybrids. It is present in far fewer departments in the south and west of France.