Caladenia polychroma Joseph's Spider Orchid Endemic
This is a difficult genus in which to identify plants to species level. There are variations within many species which seem to overlap with others. Caladenia polychroma can be distinctly reddish in overall colour or the red flecks of the labellum can be more sparse making it seem overall whitish with a hint of red. Fortunately it was identified by a local expert in this particular case even though the wet weather made good photographs tricky.
This is a fairly common orchid found throughout out the Wheatbelt as well as the Jarrah Forest and Esperance Plains.