Kwinana Rockingham Mandurah Branch meeting, 17 June 2024

Daniel Heald was the speaker for our June meeting. He gave a presentation on fungi, discussing around 30 fungi to describe fungal diversity in the environment.

Some estimates put the number of species of fungi in the 2.2 to 3.8 million range, and within that range, there is a huge variation in size. For example, the Humungous Fungus (Armillaria ostoyae) covers huge areas and can weigh up to 100 tonnes. Phlebopus marginatus, a Bolete, is Australia’s largest terrestrial mushroom (the fruiting body can weigh up to 29kg).  

Daniel then went on to discuss how certain types of fungi specialise; for example, Pleurotus ostreatus is carnivorous, eating Nematode worms as well as decomposing wood; the Banksiamyces are only found on Banksia seed cones; and the Cordiceps are parasites of fauna. Some fungi are harmful to humans, causing Ringworm, Tinia and toenail fungi and can be difficult to treat, while Batrachytrium dendodrobatis, the Chytrid fungus has devastated frog populations around the globe. Many fungi are plant pathogens causing plant dieback, but some can be useful in combating weed species; for example, Puccinia myrsiphilli, Bridal Creeper Rust, is used to biocontrol this invasive weed.

Daniel then discussed the many diverse methods fungi use to disperse spores; some, such as Aseroe rubra (Anemone Stinkhorn), use scent, and others, such as the Ghost Fungus (Omphalotus nidiformis) use bioluminescence. Some species use ‘ballistic’ methods to spread spores; examples are the Cannonball Fungus and Sphaerobolus stellatus, which forcibly eject their spores considerable distances. The Pilobolus species are found on the scat of herbivores, only producing fruiting bodies after having passed through the digestive system of an herbivore. These fruiting bodies then use ‘ballistic’ spore dispersal to spread the spores up to three metres from the parent body.

The last group of fungi discussed was those that have been ‘domesticated’ for human food preparation. They include Saccharomyces cerevisiae (Brewers’ Yeast, Bakers’ Yeast), Aspergillus oryzae (used for Soy Sauce production) and Penicillium roqueforti, used in Blue Cheese.

Daniel finished his presentation with a word of caution concerning phone apps that use artificial intelligence to identify fungi from images, as there was at least one case when a fungus image identified as a Yummy Fungus was an Aminita sp. that is deadly.  The audience thanked Daniel for a very interesting presentation.

Colin Prickett