Morganella purpurascens is a distinctive species, easy to identify in the field. It inhabits wet forests with old trees and large fallen timber. Many of the forest systems that were its habitat have been cleared and those that remain have had mature timber removed by logging. The remaining forest is still being cleared and will be vulnerable to other threats resulting from climate change. Increasing periods of drought and risk of fire are the most likely to pose a threat for this species.
There are arguably four subpopulations each of which, if assessed separately, would attract a higher risk assessment. We have chosen to consider this as one population.
The generation length of this species is not known. We have taken a period of 30 years as a reasonable estimate. In that period there have been 10 functional individuals found at seven separate sites. No collections have been made in Papua New Guinea since 1953 and there is only one recent collection of this fungus in New Caledonia. There are several areas which are suitable for this fungus that are not well recorded. It is surprising that it has not been reported in North Queensland or the Northern territory.
Using the Dahlberg & Mueller (2011) methodology we think that it would be reasonable to expect there to be perhaps 5 times more sites, that is 35 locations and perhaps a population of 700 to 1000 mature individuals.
The habitat in which this species is found has declined rapidly due to land clearing and many of the remaining areas have been logged. The sites in which these collections have been made are mostly small and under some recreational pressure. None of the current locations have been damaged by fire but this will pose a threat for this species as the climate warms.
It would be classified as “vulnerable “under criteria B2a because of the small number of locations at which the species is found and the decline of its habitat, and under criteria D1 because of the small population size.
Why suggested for a Global Red List Assessment?
This is a readily recognised saprotrophic species. Far less common than other wood inhabiting gasteromycetes such as Lycoperdon pyriforme. It is found in wet forests in the subtropics and in humid temperate forests in Victoria. It is probably a good indicator for the continuing health of stable forest containing mature trees. It is nominally protected in national parks and reserves, but the value of old logs as an important part of forest regeneration and renewal and the role of saprotrophic fungi in that process is not widely recognized. As far as we are aware, saprotrophic fungi do not figure in any National Park or Botanical Reserve management plans in Australia or Papua New Guinea or New Caledonia.