Marasmius siccus, or orange pinwheel,[1] is a small orange mushroom in the Marasmius genus, with a "beach umbrella"-shaped cap. The tough shiny bare stem is pale at the top but reddish brown below, and the gills are whitish. The stem is 3–7 centimetres (1.2–2.8 in) tall and the cap is 0.5–2.5 centimetres (0.20–0.98 in) wide.
