Gyrostomum scyphuliferum

Members of the Graphidaceae family have spores that stain purple when potassium iodide is added, although those of the genera Phaeographis and Phaeographina may become only slightly so.

Spores of Gyrostomum are transversely septate as well as having at least some cells also being divided vertically, a condition called muriform. At maturity most of the cells will be divided in this fashion.