This is a distinctive species with a small conical brown cap, and microscopic exmination reveals clamp connections. It has a small population which is widely scattered. There are 5 collections at 5 widely separated locations. Assuming that the fungus is mycorrhizal and following Dahlberg & Mueller’s guidance we have estimated that for each of the 5 functional individuals there will be 10 mature individuals. We have also allowed for twice the number of sites to allow for as yet undiscovered locations. That results in a population of 500 at 10 locations. GeoCat analysis suggests designation as Endangered based on the Area of Occupancy, but in view of the uncertainities about the ecology and life mode we propose that it be designated as vulnerable.
Phaeocollybia minuta Horak is a well defined species that appears to be naturally rare. Its small size (cap < 15 mm diam) is its most important field character, microscopically it has abundant clamp connections.
Proposed by Pat Leonard. Known from 5 collections from 5 locations. Extent of Occurrence 21,618.443 km2 Area of Occupancy 20.000 km2. Phaeocollybias appear to be naturally rare and are probably at risk of stochastic events. In simple terms we know so little about this group of fungi that we may loose them through ignorance!
A single collection in North Island and three in South Island
Only 4 collections are known. There were no collections for 30 years following its description, then three were found in the decade from 2000, but none since.
Horak speculates on the ecology of Phaeocollybia, it is known to associate with conifers in the northern hemisphere. In New Zealand it is found in Nothofagus forests but these almost always also contain some conifers. It is thought that Phaeocollybias are ectomycorrhizal but there is also some speculation that they may be weak parasites on tree roots. The type and two of the other collections were made in forests of Mountain Beech, Nothofagus solandrii var cliffortoides. Whether there is some association between this tree and the fungus is not known.
All the known locations for this species are in Nothofagus forest and are in protected areas. Nothofagus solandrii var cliffortoides is not thought to be under threat. Feral animals are not known to be a particular threat to these fungi. Until there is a better understanding of the hosts and the fungus’s relationship with them, the precise nature and degree of threat will remain uncertain. The small and scattered population makes them vulnerable to stochastic events.
Defining the nature of the relationship between Phaeocollybia minuta and its host or hosts is essential to preparing effective conservation action.
Dahlberg A. and Mueller G.M. (2011) Applying IUCN red-listing criteria for assessing and reporting on the conservation status of fungal species. Fungal Ecology 4: 147-162.
Geospatial Conservation Assessment Tool: geocat.kew.org
Global Biodiversity Information Facility: gbif.org
Horak, E. (1973). Fungi agaricini Novaezelandiae I-V. Beihefte zur Nova Hedwigia. 43:1-200
Manaaki Whenau - Landcare Research databases: https://nzfungi2.landcareresearch.co.nz/