Thursday 18 January 2018

A Cortinarius with a volva

By Sapphire McMullan-Fisher and Katrina Syme

The Australian mushroom Cortinarius phalarus is an oddity. Some species of Cortinarius have large swollen stem bases, but this particular species goes one step further and has a volva (a cup-shaped remnant of the universal veil that forms at the base of the stem). Other Cortinarius around the world in the subgenus Leprocybe that may have a volva include the C. clandestinus group, C. subalpinus and C. parkeri.

Cortinarius phalarus has a white volva at the base of the stem and may have white veil remains on the cap;
near Tingledale, WA (Image: K. Syme CC-BY-NC).

In June 2017, SMF found some Cortinarius phalarus on Mornington Peninsula (Victoria) at Greens Bush when out with the Main Creek Catchment Landcare Group. I hadn’t seen it since foraying with Katrina at Tingledale, west of Denmark in south-west Western Australia. Funny how we can learn the ‘look’ of particular genera but then encounter species that ‘break the rules’. I guess for beginners this would be very confusing.

Map of records of Cortinarius phalarus
(Atlas of Living Australia, accessed 14 Aug 2017). 
  
With nearly a hundred records in the Atlas of Living Australia (ALA), we can say that while not widespread, C. phalarus does pop up in particular localities. So far it has been found in three states (Table 1). The ALA is an amazing resource – from it I could find out that our sighting in June was not a new record for the Mornington Peninsula, as I had thought, but it was the first record since 2006, when it was recorded by Richard Hartland. What surprises us is that this distinctive species had not been seen for a decade, even though the FNCV foray group has visited Greens Bush often in recent years.



From the ALA, the most common associated vegetation types for Cortinarius phalarus (Table 2) include two types of ‘Eucalyptus open forests’ and also ‘Low closed forest or tall closed shrublands’.


History of Cortinarius phalarus


In 1989, when KS was still learning about fungi, Roger Hilton (a Senior Lecturer at University of Western Australia) was my kind and generous mentor. By then, I could generally work out fungi genera, but always contacted Roger if I was puzzled. When I found a fungus button covered in a thin white sac and mature fruit bodies with cup-shaped volvas and white patches on the cap – but rusty brown spores, I knew it was strange. The collection made at this site became the type for Cortinarius phalarus.

Help us know more about Cortinarius phalarus


If you have seen this species  please send sightings to Fungimap. We want to know more about the biology of Australian Fungi, particularly the type of vegetation that is associated with different species.


Habitat of Cortinarius phalarus near Tingledale, WA - closed shrubland with Tea-tree (Taxandia parviceps),
(Image: K. Syme CC-BY-NC).


References


Atlas of Living Australia (2017) Occurrence for Cortinarius phalarus, from datasets: Western Australian Herbarium, National Herbarium of Victoria, Australia's Virtual Herbarium, Fungimap, Western Australia, Department of Parks and Wildlife, Individual Sightings, BowerBird, Tasmanian Natural Values Atlas, Citizen Science - ALA Website and Royal Botanic Gardens Victoria. Accessed 14 Aug 2017.

Horton B (2006) Mushrooms of Maatsuyker Island. The Tasmanian Naturalist 128: 11-22.

Miller D, Leprocybe, in Pictorial Key to Mushrooms of the Pacific Northwest. Accessed 8 Aug 2017.