Rare and endangered fungi
New Zealand fungi have been formally recognised as threatened since 2002. Fifty species of fungi were listed as Nationally Critical in 2002 in the New Zealand Threat Classification System Lists.
Assessments of fungal threat status have been mostly limited to macrofungi - those fungi with fruiting bodies that are readily visible to the naked eye and for which distribution and host relationships should theoretically be best known. However, among native microfungi are species confined to a single host plant species. If that host is a threatened species the associated, and often overlooked, fungus is arguably more threatened than the plant!
Data-deficient fungi
More than 1,200 species were listed as Data Deficient in the 2002 assessment of threatened fungi. These species were known from few specimens (Appendix 2), or were originally described from New Zealand but have no specimens in a local collection (Appendix 3).
Recent projects funded by the Department of Conservation have used a range of methods including taxonomic and biogeographic assessment, examination of historical collections including types, targeted field collecting, and supplementation of specimen data with records accumulated in ecological surveys, to reconsider the Data Deficient status of ectomycorrhizal mushrooms, discomycete fungi, and plant pathogens including rusts. These studies have recommended the removal of more than 180 species from the Data Deficient category.