These striking mushrooms belongs to the species Cortinarius archeri (Cortinariaceae), a mycorrhizal fungus that is common in many eucalypt forests in Australia. It is very common in June and July, and seems to thrive in recently burnt forest.
Caps of this mushroom are violet and up to 10 cm wide. Both cap and stem are viscid when young. Besides its attractive color, the most distinctive feature of Cortinarius archeri is the presence of a partial veil covering young gills. This veil disintegrates as the fruit body matures, leaving a ring-zone on the stem, or disappearing altogether.
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Photo credit: ©greenzaku | Locality: Great Dividing Trail, Victoria, Australia