Calochilus robertsonii By Matt Young August 20, 2009 12:00 MST Photograph by James Wood. Photography contest, “Vegetable” category. Calochilus robertsonii – peloric mutant of purple beard orchid flowering in the Peter Murrell Reserve, Tasmania. This species is apparently prone to developmental errors so that the labellum can be petaloid or (as in this case) all the petals develop the labellum (lip) characteristics.