Comparative Anatomy of the Lip Spur and Additional Lateral Sepal Spurs in a Three-Spurred Form (f. fumeauxiana) of Anacamptis pyramidalis

Anacamptis pyramidalis shows great phenotypic variability. Additional lateral sepal spurs were observed in f. fumeauxiana. We used light and scanning electron microscopy to examine the anatomy of the lip spur and additional lateral sepal spur(s). The spurs have the same anatomical structure. We describe the features of the inner and external epidermis, report the presence of an appendix at the base of the additional spur, and discuss the evolutionary context