Macrolepiota eucharis is a distinctive species , relatively easy to identify in the field. Its very dark squamules and stipe distinguish it from other Macrolepiotas.
There have only ever been 3 functional individuals found at two separate sites. One of the authors of the species (Halling) has undertaken extensive surveys in north Queensland and south east Queensland and in New South Wales, but has not found new localities for this species.
Using the Dahlberg & Mueller (2011) methodology we think that it would be reasonable to expect the population and distribution to be perhaps 5 times greater, that is 15 locations and up to 200 mature individuals.
The habitat in which this species is found has declined rapidly as it is much in demand for beef farming and for development in coastal areas. The sites in which these collections have been made have been damaged by fire and are grazed by feral animals including deer and pigs which are understood to consume Macrolepiota species.
It would be classified as “endangered “under criteria B2a & b because of the small range of the species and the decline and fragmentation of its habitat, and under criteria D1 because of the small population size.
Macrolepiota eucharis Vellinga & Halling, sp. nov.
Pileus: up to 6 cm broad when expanded; parabolic at first then convex; dry, surface breaking up into areolate black scales, more densely packed toward disc, scattered and detersile toward margin; overlying a felty, radially oriented subsquamulose-fibrillose layer; scales black, on greyish-brown (6E5–6E4) background.
Lamellae: free; crowded; white with fimbriate, concolourous edge; up to 8 mm broad.
Stipe: tall, 11–14 cm long, 6–7 mm broad near apex; equal with a bulbous base; terete, dry, uniformly fibrillose; dark brown (7F4); stipe base volvate to marginately bulbous, paler to concolourous with stipe surface, with free limb, with some dark minute scales, as on pileus surface. Annulus ascending; simple; white above and below; with dark minute patches on underside near margin, with fringed margin.
Flesh: white; not changing on exposure to air; 7 mm thick in pileus.
Smell and taste: mild.
Spores: ellipsoidal to oblong and amygdaloid in side view; 10.8–15.5 × 7.1–9.1 μm, average 12.0–12.4 × 7.9 μm, Q = 1.4–1.8, average Q = 1.53–1.58; with apical and central germ pore; thick-walled; congophilous, dextrinoid; metachromatic in Cresyl Blue and cyanophilous.
Basidia: 27–40 × 9.5–13 μm, 4-spored, some 2-spored.
Cheilocystidia: 25–53 × 5.0–12 μm, cylindrical, narrowly clavate, or slightly fusiform; forming a sterile edge to the gill; slightly thick-walled, colourless.
Pileus: a trichoderm
Macrolepiota eucharis is a species of agaric fungus in the family Agaricaceae. It is saprotrophic. It has only been found in Queensland, Australia, where it grows under Eucalyptus grandis and Allocasuarina littoralis in rainforests. It was described as new to science in 2003 by mycologists Else Vellinga and Roy Halling, from collections made in Queensland. The specific epithet derives from the Ancient Greek word ευχαρις, which means “charming, lovely, attractive”. The tall fruitbody of the fungus is characterised by dark grey to black cap, a volva at the base of the stipe, and microscopically by its small spores and narrowly club-shaped and cylindrical cheliocystidia.
The collection of data on the distribution and population of fungi in Queensland was almost wholly dependant on the work of the staff at the Queensland herbarium until 1995. The herbarium currently holds 5200 fungal specimens accumulated over 150 years. Recording has undergone considerable change in the past 25 years. The foundation of Fungimap in 1995 engaged citizen scientists in recording fungi and those records are now part of the ALA database. Over 100,000 records have been collected by Fungimap some of which were for Queensland. In 2005 the Queensland Mycological Society was founded and began a program of organised forays mainly focused on South East Queensland. About 300 days of effort are expended annually by members and some 4000 records have been made. More recently the creation of a South East Queensland Facebook group has allowed other naturalists to contribute information on the sighting of fungi over a wider area of the state. All this effort means that fungal records are more extensive in the last decade than in previous periods. This makes it difficult to establish trends, but also means that there is now a greater degree of accuracy about the size and distribution of fungal populations.
Halling who is one of the authors who described this taxon, has carried out lengthy surveys of its habitat over a number of years and this adds considerably to our confidence in the population size.
Population Trend: Uncertain
Macrolepiota eucharis is solitary or in small groups, in rainforests, under Eucalyptus grandis and Allocasuarina littoralis. Known from two places 80 Kilometers apart in the Wet Tropics and from a site in the Rainbow Beach section of the Great Sandy National Park..
Land Clearing has reduced the extent of habitat significantly. In 2013, less than about 30% of the pre-settlement habitat remained. Land clearing continues in Queensland and the quality of the remaining habitat is reduced by the presence of numerous feral animals and through burning.
Whilst National Parks appear to be protected from most of the past threats, fungi are not recognised in conservation management plans and therefor any future changes may not favour the conservation of this species.
Feral animals have a big impact upon many Australian habitats. In these habitats cattle, horses, pigs and deer are all potential problems for fungi and their hosts. It is thought wild pigs and cattle may have the most significant effects. Pigs through digging large areas of soil and consumption of fruit bodies and cattle through trampling and increasing nitrogen levels.
Also, all three of these sites are close to heavily used recreational areas and or roadsides even though they are in National Parks and forest reserves, and all this extra human traffic poses a further threat by the probable introduction of counter productive weedy plant and fungal species.
Future threats also include the effects of climate change. Increasing temperatures, longer and more intense droughts and higher intensity of storms are all already being experienced at the localities inhabited by this fungus.(http://www.climatechangeinaustralia.gov.au).
This taxon occurs in a forest reserve and two National Parks, all of which have management plans (DNPSR). Writing the species into the management plans would lead to proper consideration of its conservation. Action may be needed to amend fire management regimes if, as seems likely, this fungus is shown to be vulnerable to fire.
The life cycle and habitat requirements of this species and of other saprotrophic species are poorly understood. Research is needed to elucidate this and to formulate effective management plans.
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.
Neldner, V.J., M.J. Laidlaw, K.R. McDonald, M.T. Mathieson, R.I. Melzer, R. Seaton, W.J. F. McDonald, R. Hobson, and C.J. Limpus (2017). Scientific review of the impacts of land clearing on threatened species in Queensland. Queensland Government, Brisbane.
Vellinga EC. (2003). “Chlorophyllum and Macrolepiota (Agaricaceae) in Australia” (PDF). Australian Systematic Botany 16 (3): 361–370