This species is described from one specimen by Trappe et al. in 1996 from a specimen collected in 1993. The following is a quote from the species remarks:
“Mesophellia westresii at first appeared to be small specimens of M. labyrinthina, except for the pinkish hue of the glebal core and the rather narrow endoperidium. Microscopy revealed, however, that its tissues were composed of much narrower hyphae than those of M. labyrinthina; this was particularly striking in the glebal core: the core hyphae of M. westresii are 1.5-3 pm in diameter, those of M. labyrinthina 5-6 pm in diameter.”
There is only one record for this species, the type for which it is described. This specimen was collected in 1993 and the species erected in 1996 (Trappe et al.). The location where is this species was collected is still a State Forest, although it is small in area and highly fragmented. There are other fragmented State Forest’s within 50 km of its collection location. It is possible that this species survives within these forest fragments. There is one record for ‘Mesophellia cf. westresii’ collected by W. Dunstan in May 2000 at ‘Boranup, Stewart rd. at 4-Acre rd.’ (data supplied by Michael Castellano). Further surveys are needed to confirm this.
Threats to this species include habitat clearing, declining habitat quality and host range through forest dieback from Phytophora and decline of mammalian dispersers.
Williams, Western Australia (“4.6 km from the junction of Wandering and Williams Road, Dryandra State Forest” on specimen notes). The lat/long recorded on ALA for this specimen is -32.83333333, 116.8833333.
There is one record for ‘Mesophellia cf. westresii’ collected by W. Dunstan in May 2000 at ‘Boranup, Stewart rd. at 4-Acre rd.’ (data supplied by Michael Castellano).
Population Trend: Uncertain
All members of Mesophelliaceae are thought to be ectomycorrhizal and incorporate ectomycorrhizae in their peridium. This species was recorded under Eucalyptus accedens in a Mediterranean climate. All Mesophellia sp. require animals for dispersal, mainly mammals. The mammals break open the crusty outer layers to reach a sterile edible core. In doing so the powdery spores are dispersed via either ingestion by the animal, carried on the outside of the animal or dispersed via wind or soil movement.
As this is an ectomycorrhizal species the main threat would be land clearing.
Jarrah forest, which is the habitat for this species, is heavily impacted by forest dieback caused by Phytophthora sp. This pathogen causes mortality in trees and can adversely affect the abundance and diversity of ectomycorrhizal fungi in affected forests (Anderson et al. 2010).
All Mesophellia sp. require animal dispersal to dig up and expose their spores. The spores are then either dispersed by the animal, via wind or soil movement. This is mainly done my mycophagous mammals. Therefore, local extinction of mycophagous mammals can also pose as a threat to this species. Within the south-west of WA, two specialist mycophagous mammals are now Critically Endangered. These are the Gilbert’s Potoroo, Potorous gilbertii, and Woylie, Bettongia penicillata ogilbyi. These species were most probably the main dispersers for truffle-like fungi in this region (Nuske et al. 2017) and now exist in remnant, fragmented populations. One of B. penicillata ogilbyi’s remnant populations was (is?) at Dryandra SF, the same location that M. westresii was recorded. This Bettong species used to be very wide spread acorss Australia and now exists in ~1% of its former range (Department of Parks and Wildlife, Western Australia). The Gilbert’s Potoroo used to be wide spread throughout the south-west of WA but now only exists in isolated populations at Two Peoples Bay and nearby islands (~270 km from Dryandra SF).
Other mycophagous mammals that exist in this area and could contribute to dispersal of M. westresii are
- wallabies (Macropus eugenii, Least Concern; Macropus irma, Near Threatened in WA, Least Concern nationally),
- bandicoots (Isoodon obesulus, Least Concern nationally, I. o. fusciventer subspecies is endemic to south-west WA, listed as Least Concern but recent surveys show it is declining (WWF-Australia and Department of Parks and Wildlife 2012)),
- rodents (Rattus fuscipes, Least Concern; Pseudomys albocinereus, Least Concern; Rattus rattus, Introduced; Mus musculus, Introduced),
- possums (Pseudocheirus occidentalis, Critically Endangered; Pseudocheirus peregrinus, Least Concern nationally but less common in south-west WA), Trichosurus vulpecula, Least Concern nationally but subspecies endemic to south-west WA, T. v. vulpecula is Endangered and T. v. hypoleucus has declined and is Near Threatened),
- quokka (Setonix brachyurus; Vulnerable).
Further research is needed to determine whether these other mycophagous species can maintain the dispersal of populations of M. westreii and other endemic truffles in south-east WA in the absence of specialist mycophagists (bettongs and potoroos).
There are currently no conservation actions for this species
- Sequencing of type specimen to confirm species distinctiveness
- Targeted searches for this species in similar habitat
- Dispersal ecology of M. westreii. Particularly the dispersal by a variety of mycophagous mammals (rats, bandicoots, wallabies) and the role of Critically Endangered specialist mycophagous mammals (bettongs and potoroos)
- habitat characterisation and ecotomycorrhizal host range
- Identification of Mesophellia sp. collections in herbaria (note: there are 111 records of on the Australian Living Atlas recorded as Mesophellia sp.)
Advice to the Minister for the Environment, Heritage and the Arts from the Threatened Species Scientific Committee on Amendment to the list of Threatened Subspecies under the Environment Protection and Biodiversity Conservation Act 1999. 2008. . https://www.dpaw.wa.gov.au/images/documents/plants…/woylie_fauna_profile.pdf
Anderson, P., M. Brundrett, P. Grierson, and R. Robinson. 2010. Impact of severe forest dieback caused by Phytophthora cinnamomi on macrofungal diversity in the northern jarrah forest of Western Australia. Forest Ecology and Management 259:1033–1040.
Bougher, N. L., and J. A. Friend. 2009. Fungi consumed by translocated Gilbert’s potoroos (Potorous gilbertii) at two sites with contrasting vegetation, south coastal Western Australia. Australian Mammalogy 31:97–105.
Nuske, S. J., K. Vernes, T. W. May, A. W. Claridge, B. C. Congdon, A. Krockenberger, and S. E. Abell. 2017. Redundancy among mammalian fungal dispersers and the importance of declining specialists. Fungal Ecology 27:1–13.
Trappe, J. M., M. A. Castellano, and N. Malajczuk. 1996. Australasian Truffle-like Fungi. VII. Mesophellia (Basidiomycotina, Mesophelliaceae). Australian Systematic Botany 9:773–802.
WWF-Australia, ., and W. A. Department of Parks and Wildlife. 2012. Community Quenda Survey 2012 Report.
Zosky, K. L., A. F. Wayne, K. A. Bryant, M. C. Calver, and F. R. Scarff. 2017. Diet of the critically endangered woylie (Bettongia penicillata ogilbyi) in south-Western Australia. Australian Journal of Zoology 65:302–312.