Boletopsis nothofagi

Boletopsis nothofagi is a fungus in the family Bankeraceae. The fungus forms grey fruit bodies that grow in clusters. Like all species of Boletopsis, it has a porous spore-bearing surface on the underside of the cap, but differs from other species of Boletopsis by having characteristics such as elongated spores and a green discoloration when stained with potassium hydroxide. Boletopsis nothofagi is endemic to New Zealand and has a mycorrhizal association with red beech (Nothofagus fusca). It is unknown when exactly the fungus forms its fruit body, but it has so far been found solely in May, during autumn in the Southern Hemisphere.

The first description of B. nothofagi was published in 2012 by Jerry A. Cooper and Patrick Leonard. DNA studies of the fungus suggest that it is a somewhat basal member of the genus Boletopsis. The fungus is most likely a native species of New Zealand and was present there before the arrival of Europeans. As it is very rare and possibly threatened, B. nothofagi is listed in the Red List of Threatened Species as an endangered species.